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LET'S MAKE ITCHING ANCIENT HISTORY - APRIL 20, 2021 | FREE VIRTUAL EVENT SCIENTIFIC PROCEEDINGS - Hill's Global ...
LET’S MAKE ITCHING
                         ANCIENT HISTORY
                             APRIL 20, 2021 | FREE VIRTUAL EVENT

                                   SCIENTIFIC PROCEEDINGS
                                     HillsGlobalSymposium.com

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                                             CONTENTS
                                                  3 U
                                                     pdate on Human Atopic Dermatitis
                                                    (Donald Leung, USA)
                                                  5	
                                                    Simplifying the Pruritic Dog
                                                    (Darren Berger, USA)
                                                  8	
                                                    Getting the Most Out of the Teledermatology
                                                    Consultation
                                                    (Richard P. Usatine, USA)
                                                 11	
                                                    Multimodal Treatment of Atopic Dermatitis – the Four
                                                    Most Important Concepts to Know
                                                    (Douglas J. DeBoer, USA)
                                                14 H
                                                    ocus Pocus Veterinary Dermatology Curtain Lifted
                                                   and Myths Revealed
                                                   (Christina Restrepo, USA)
                                                20	
                                                   Nutritional Approach to Dogs With Atopic Dermatitis
                                                   (Dana Hutchinson, USA)
                                                24	
                                                   Using Psychology to Help Pet Parents Tackle Atopic
                                                   Dermatitis
                                                   (Thomas Webb, UK)
                                                27	
                                                   Let’s Make Itching Ancient History: Innovation in
                                                   Nutritional Management of Atopic Dermatitis and
                                                   Food Allergies in Dogs
                                                   (Jennifer M. MacLeay, USA)
                                                 31	
                                                    Debunking Nutrition Myths for Allergic Pets
                                                    (Jennifer A. Larsen, USA)
                                                    (Julie A. Churchill, USA)
                                                34	
                                                   Canine Atopic Dermatitis: How to Use the Newest
                                                   Drugs in Clinical Practice?
                                                   (Wayne Rosenkrantz, USA)
                                                38	
                                                   More Than Crusty Skin Pics: Using Social Media in
                                                   Veterinary Dermatology
                                                   (Ashley Bourgeois, USA)

                                             Click on any title to access the article
                                             Editors:
                                             Dr Maureen Revington BVSc, MSc, PhD
                                             S Dru Forrester DVM, MS, DACVIM
                                             Iveta Bečvářová DVM, MS, DACVN

                                             The comments and opinions are those of the authors, and do not necessarily reflect the position or beliefs
                                             of Hill’s Pet Nutrition, Inc or its employees. ISSN 1479 - 8999

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                                             UPDATE ON HUMAN ATOPIC DERMATITIS

                                                                         Donald Leung, MD, PhD
                                                                         Edelstein Chair of Pediatric Allergy-Immunology
                                                                         National Jewish Health
                                                                         Denver, CO, USA

                                             Atopic dermatitis (AD) is a highly pruritic chronic          AD.12-14 These studies demonstrate that epidermal
                                             inflammatory skin disorder affecting 10-25% of children      profiles from AD with peanut allergy is associated with
                                             worldwide and approximately 7% of adults.1 It often          high TEWL values, particularly after skin tape stripping,
                                             predates or is found in association with childhood           high Type 2 immune activation, Staphylococcus
                                             food allergy (FA), asthma, and allergic rhinitis.2 Recent    aureus colonization, reduced filaggrin breakdown
                                             studies have demonstrated that AD is associated              products, and a reduced proportion of long-chained
                                             with epidermal barrier dysfunction allowing tissue           lipid products. Lamellar bilayer structural integrity is
                                             penetration of allergens, irritants, and microbes, which     highly organized in normal skin but very abnormal
                                             elicit skin inflammation.3,4 Causes of the abnormal skin     in electron micrographs of skin layers from AD with
                                             barrier are complex and driven by a combination of           peanut allergy. These observations are consistent
                                             genetic variants, environmental triggers, immunologic        with a defective skin barrier in patients with AD and
                                             factors that affect gene expression, and the profile of      peanut allergy, predisposing to epicutaneous allergen
                                             proteins and lipids in the epidermis.5,6 Variability in      sensitization.4 Interestingly, low filaggrin has also been
                                             the occurrence of these factors likely accounts for the      found in the skin of peanut-allergic patients (without
                                             heterogeneity of AD onset, severity, and natural history     AD) supporting the importance of targeting research
                                             of this skin disease. Filaggrin (FLG) gene mutations, in     and treatment even in nonlesional skin.15
                                             particular, are the most profound single gene defects
                                                                                                          Skin tape proteomics reveal evidence for lack of
                                             identified in AD, but the most common cause of FLG
                                                                                                          epidermal terminal differentiation in AD, particularly
                                             deficiency stems from skin immune activation and
                                                                                                          involving those patients who have associated food
                                             environmental factors.
                                                                                                          allergy.16 Although skin tape stripping only samples the
                                             A major function of the epidermis is to protect the          stratum corneum and upper granular layers of the skin,
                                             host from potentially damaging environmental factors         increased amounts of KRT5 and KRT14 amounts were
                                             and reduction of transepidermal water loss (TEWL).           observed in the skin of AD patients with food allergy
                                             In infants, increased TEWL can be detected prior to          as compared with AD only and healthy controls.17 This
                                             the onset of clinical disease. The onset of AD has           is unusual because KRT5 and KRT14 are predominantly
                                             been linked to early colonization with Staphylococcus        expressed       by      undifferentiated     proliferating
                                             aureus and expression of epidermal thymic stromal            keratinocytes in the basal layer of the epidermis.
                                             lymphopoietin (TSLP), even before the onset of clinical      These observations suggest that the superficial layer
                                             or lesional eczema.7-11 Epidermal injury by scratching,      of skin in patients with AD FA+ is characterized by
                                             allergens, microbes and irritants (such as detergents        keratinocytes that hyperproliferate, impairing their
                                             and pollution) lead to the release of epithelial cytokines   ability to terminally differentiate, thus accounting for
                                             such as thymic stromal lymphopoietin (TSLP) and              the low filaggrin, lipid abnormalities, increased TEWL,
                                             Interleukin (IL)-33, which play a pivotal role in driving    and microbiome abnormalities that characterize AD
                                             type 2 immune and inflammatory responses through             skin in patients with food allergy.
                                             the activation of dendritic cells, innate lymphoid (ILC)
                                                                                                          Skin-gut interactions have now been demonstrated in
                                             type 2 cells, and Th2 cells. Although cytokines such
                                                                                                          experimental animals with eczema and food allergy.18
                                             as Interferon (IFN)-g, IL-17, and IL-22 can modify the
                                                                                                          The immune mechanisms linking the skin to the gut
                                             course of allergic responses, type 2 cytokines such
                                                                                                          were recently shown to have their origins in skin injury-
                                             as IL-4, IL-13, TSLP, and IL-33 play a central role in the
                                                                                                          induced release of IL-33 from keratinocytes, leading
                                             development of allergic diseases.
                                                                                                          to intestinal mast cell hyperplasia and food-induced
                                             Using a minimally invasive skin tape sampling technique,     anaphylaxis. Importantly, the systemic release of skin-
                                             our research group has demonstrated that epidermal           derived TSLP may contribute to high circulating IgE
                                             profiling of lipids, proteins, and transcriptomes can be     levels, which promote not only FA but also respiratory
                                             used to identify endotypes underlying different AD           allergy. AD pathobiology evolves from a complex
                                             phenotypes, e.g. AD with peanut allergy versus AD            interaction of epidermal barrier disruption, high type 2
                                             without peanut allergy versus peanut allergy without         immune response, and an imbalanced skin microbiota

                                             3

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                                             that promotes cutaneous barrier dysfunction. The                              emollients been optimized for skin barrier repair.
                                             development of noninvasive skin sampling techniques                           Indeed, a recent study demonstrated a trilipid cream
                                             will allow early identification of abnormalities in the                       was more effective than a paraffin-based emollient in
                                             skin barrier and facilitate early intervention in young                       reducing TEWL and serum IgE levels.20,21 Once immune
                                             infants.                                                                      activation is established, even in nonlesional AD, it is
                                                                                                                           important to effectively control cytokine actions with
                                             These new skin sampling approaches may play an
                                                                                                                           proactive therapy. This may become possible with novel
                                             important role in the identification of infants with early
                                                                                                                           pathogenesis-based topical and systemic therapies.
                                             epidermal barrier dysfunction and facilitate the timely
                                                                                                                           Finally, The National Institute of Allergy and Infectious
                                             introduction of novel therapies targeting infants who
                                                                                                                           Diseases (NIAID) Atopic Dermatitis Research Network
                                             have skin barrier dysfunction, nonlesional immune
                                                                                                                           has studied a human skin commensal microbial therapy
                                             activation, and microbial dysbiosis.19 Although there
                                                                                                                           to control Staphylococcus aureus colonization.22 Using
                                             has been considerable controversy whether early
                                                                                                                           a multi-pronged approach to target the skin barrier
                                             introduction of skin emollients can prevent AD and
                                                                                                                           dysfunction, microbial dysbiosis and underlying
                                             food allergy, these studies have not targeted high-
                                                                                                                           skin inflammation in early infancy are likely to give
                                             risk infants with pre-existing evidence for skin barrier
                                                                                                                           clinicians the best opportunity at controlling AD and its
                                             dysfunction, many studies have not considered lack
                                                                                                                           associated atopic co-morbidities.
                                             of adherence, nor have the ingredients of these skin

                                             References                                                                    13. Berdyshev E, Goleva E, Bronova I, Dyjack N, Rios C, Jung J, Taylor
                                               1. Leung DYM, Guttman-Yassky E. Deciphering the complexities of                 P, Jeong M, Hall CF, Richers BN, Norquest KA, Zheng T, Seibold M,
                                                   atopic dermatitis: shifting paradigms in treatment approaches. J             Leung DY. Lipid abnormalities in atopic skin are driven by Type
                                                   Allergy Clin Immunol. 2014;134:769-79. PMCID: PMC4186710                     2 cytokines. JCI Insight. 2018;3(4):e98006. PMCID: PMC5916244.
                                              2. Davidson WF, Leung DYM, Beck LA, Berin CM, Boguniewicz M,                14. Leung DYM, Calatroni A, Zaramela LS, LeBeau PK, Dyjack N, Brar
                                                  Busse WW, Chatila TA, Geha RS, Gern JE, Guttman-Yassky E, Irvine              K, David G, Johnson K, Leung S, Ramirez-Gama M, Liang B, Rios
                                                  AD, Kim BS, King HH, Lack G, Nadeau KC, Schwaninger J, Simpson                C, Montgomery MT, Richers BN, Hall CF, Norquest KA, Jung J,
                                                  A, Simpson EL, Spergel JM, Togias A, Wahn U, Wood RA, Woodfolk                Bronova I, Kreimer S, Talbot CC Jr, Crumrine D, Cole RN, Elias P,
                                                  JA, Ziegler SF, Plaut M. Report from the National Institute of                Zengler K, Seibold MA, Berdyshev E, Goleva E. The nonlesional
                                                  Allergy and Infectious Diseases workshop on “Atopic dermatitis                skin surface distinguishes atopic dermatitis with food allergy as
                                                  and the atopic march: Mechanisms and interventions.” J Allergy                a unique endotype. Sci Transl Med. 2019;11(480):eaav2685. PMID:
                                                  Clin Immunol. 2019;143(3):894-913. PMCID: PMC6905466.                         30787169
                                              3. Walker MT, Green JE, Ferrie RP, Queener AM, Kaplan MH, Cook-             15. Berdyshev E, Goleva E, Bronova I, Bronoff AS, Hoffman BC,
                                                  Mills JM. Mechanism for initiation of food allergy: dependence on             Ramirez-Gama MA, Garcia SL, Crumrine D, Elias PM, Cho CB, Leung
                                                  skin barrier mutations and environmental allergen costimulation. J            DYM. Unique skin abnormality in patients with peanut allergy but
                                                  Allergy Clin Immunol 2018;141: 1711-25.                                       no atopic dermatitis. J Allergy Clin Immunol. 2021;147(1):361-367.
                                              4.  Brough HA, Nadeau KC, Sindher SB, Alkotob SS, Chan S,                        e1. PMID: 32615171.
                                                   Bahnson H, Leung DYM, Lack G. Epicutaneous sensitization in             16. Goleva E, Calatroni A, LeBeau P, Berdyshev E, Taylor P, Kreimer
                                                   the development of food allergy: what is the evidence and how                S, Cole RN, Leung DYM. Skin tape proteomics identifies
                                                   can this be prevented? Allergy. Apr 2020;75(9):2185–2205. PMID:              pathways associated with transepidermal water loss and allergen
                                                   32249942                                                                     polysensitization in atopic dermatitis. J Allergy Clin Immunol.
                                              5. Leung DYM, Berdyshev E, Goleva E. Cutaneous Barrier Dysfunction               2020;146(6):1367-1378. PMID: 32360271
                                                  in Allergic Diseases. J Allergy Clin Immunol. June 2020;145(6):1485-     17. Kim BE, Goleva E, Kim PS, Norquest K, Bronchick C, Taylor P,
                                                  1497. PMCID: PMC7291847                                                       Leung DYM. Side-by-side comparison of skin biopsies and skin
                                              6. Goleva E, Berdyshev E, Leung DY. Epithelial barrier repair and                tape stripping highlights abnormal stratum corneum in atopic
                                                   prevention of allergy. J Clin Invest. 2019;129(4):1463-1474. PMCID:          dermatitis. J Invest Dermatol. 2019;139(11):2387-2389.e1. PMCID:
                                                   PMC6436854                                                                   PMC6814531
                                              7. Kelleher M, Dunn-Galvin A, Hourihane JO, Murray D, Campbell              18. Leyva-Castillo JM, Galand C, Kam C, Burton O, Guish M, Musser MA,
                                                  LE, McLean WH, et al. Skin barrier dysfunction measured by                    et al. Mechanical skin injury promotes food anaphylaxis by driving
                                                  transepidermal water loss at 2 days and 2 months predates                     intestinal mast cell expansion. Immunity 2019;50:1262-75.
                                                  and predicts atopic dermatitis at 1 year. J Allergy Clin Immunol         19. Lowe AJ, Leung DYM, Tang MLK, Su JC, Allen KJ. The skin as a
                                                  2015;135:930-5.                                                               target for prevention of the atopic march. Ann Allergy Asthma
                                              8. Kelleher MM, Dunn-Galvin A, Gray C, Murray DM, Kiely M, Kenny                 Immunol. 2018;120(2);145-151. PMID: 29413338
                                                  L, et al. Skin barrier impairment at birth predicts food allergy at 2    20. Sindher S, Alkotob SS, Shojinaga MN, Brough HA, Bahnson HT,
                                                  years of age. J Allergy Clin Immunol 2016;137:1111-6.                          Chan S, Lack G, Leung DYM, Nadeau KC. Pilot study measuring
                                              9. Kim J, Kim BE, Lee J, Han Y, Jun HY, Kim H, Choi J, Leung DYM,                 transepidermal water loss (TEWL) in children suggests trilipid
                                                   Ahn K. Epidermal thymic stromal lymphopoietin predicts the                    cream is more effective than a paraffin-based emollient. Allergy.
                                                   development of atopic dermatitis during infancy. J Allergy Clin               2020;75:2662–2708. PMID: 32176320.
                                                   Immunol. 2016;137(4):1282-1285. PMID: 26879860                          21. Sindher T, Alkotob S, Shojinaga MN, Hamilto R, Chan S, Cao S,
                                             10. Kennedy EA, Connolly J, Hourihane JO, Fallon PG, McLean WHI,                  Bahnson T, Brough H, Lack G, Leung DYM, Nadeau K. Increases
                                                   Murray D, et al. Skin microbiome before development of atopic                in plasma IgG4/IgE with trilipid versus paraffin/petrolatum-
                                                   dermatitis: early colonization with commensal staphylococci at               based emollients for dry skin/eczema. Pediatr Allergy Immunol.
                                                   2 months is associated with a lower risk of atopic dermatitis at 1           2020;31(6):699-703. PMID: 32372469.
                                                   year. J Allergy Clin Immunol 2017;139:166-72.                           22. Nakatsuji T, Hata TR, Tong Y, Cheng JY, Shafiq F, Butcher AM,
                                             11. Meylan P, Lang C, Mermoud S, Johannsen A, Norrenberg S, Hohl                  Salem SS, Brinton SL, Rudman Spergel AK, Johnson K, Jepson B,
                                                   D, et al. Skin colonization by Staphylococcus aureus precedes the             Calatroni A, David G, Ramirez-Gama M, Taylor P, Leung DYM, Gallo
                                                   clinical diagnosis of atopic dermatitis in infancy. J Invest Dermatol         RL. Rational development of a human skin commensal microbe
                                                   2017;137:2497-504.                                                            for bacteriotherapy and use in a randomized clinical trial of atopic
                                                                                                                                 dermatitis. Nature Medicine. 2021. (Article in Press).
                                             12. Dyjack N, Goleva E, Rios C, Kim BE, Bin L, Taylor P, Bronchick C,
                                                   Hall CF, Richers BN, Seibold MA, Leung DYM. Minimally invasive
                                                   skin tape strip RNA sequencing identifies novel characteristics of
                                                   the type 2-high atopic dermatitis disease endotype. J Allergy Clin
                                                   Immunol. 2018;141(4):1298-1309. PMCID: PMC5892844.

                                             4

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                                             SIMPLIFYING THE PRURITIC DOG

                                                                             Darren Berger, DVM, DACVD
                                                                             Associate Professor
                                                                             Iowa State University, IA, USA

                                             Pet parents quickly seek veterinary care for their                  When presented with a pet whose main symptom
                                             animals when they are pruritic. This is often the result            is pruritus, a major consideration as to the potential
                                             of perceived discomfort or suffering on their animal’s              causes should be the patient’s signalment. Additional
                                             part. It may also be the result of disruptions in the pet           qualifying characteristics or historical insights that
                                             parent’s quality of life such as disturbing their sleep             may help narrow the differential causes are: (i) The
                                             or their bond with their pet. Regardless of the source              relationship between secondary infections and pruritus
                                             of concern, pruritic pets are frequently a source of                onset; (ii) Acute vs. chronic progression of the pruritus;
                                             frustration for both the pet parent and veterinarian, as            and (iii) Lesion location and distribution. The signalment
                                             there is a lack of “traditional tests” that reliably provide        is helpful from the standpoint of the patient’s age and
                                             an accurate diagnosis for many causes of pruritic                   breed. When considering primary causes of pruritus
                                             dermatoses.1 In many cases of pruritus, the diagnosis               certain conditions should be considered more likely
                                             is often made based on signalment, clinical suspicion,              and should likewise alter the priority placed on various
                                             and response to a therapeutic trial. This is what many              diagnostics or therapeutic trials. In addition, different
                                             of us refer to as “clinical practice”, but it many instances        breeds have been shown to be overrepresented with
                                             feels more like trial and error to the pet parent. As such,         certain pruritic conditions or those that may predispose
                                             it is important to educate the pet parent about the                 the patient to secondary infections which result in
                                             possible causes and the process to relieving their pet’s            pruritus. The author likes to break canine patients
                                             discomfort.                                                         down into three groups based on age to help prioritize
                                                                                                                 potential differentials (Table 1).

                                                 TABLE 1.
                                                 Primary differentials for pruritic patients based on the age of the
                                                 patient at the time clinical signs started.

                                                          ≤6 MONTHS OF AGE                  6 MONTHS TO 4 YEARS OF AGE                    ≥ 5 YEARS OF AGE
                                                                 Parasites                                Parasites                            Parasites
                                                                  CAFR                                       CAD                                 CAD
                                                                   CAD                                      CAFR                                 CAFR
                                                          Contact dermatitis                        Contact dermatitis                    Contact dermatitis
                                                                                                      Hypothyroidism                      Endocrinopathies
                                                                                                Autoimmune or immune-                 Autoimmune or immune-
                                                                                                  mediated conditions                   mediated conditions
                                                                                                                                      Epitheliotropic lymphoma
                                                 CAFR – Cutaneous adverse food reaction; CAD – Canine atopic dermatitis

                                             5

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                                             Once the signalment has helped establish possible            worsens. Contrary to this are disorders such as
                                             underlying etiologies, other characteristics of the          demodicosis or hypothyroidism where the patient is
                                             patient’s pruritus should be used to help prioritize         not typically pruritic until after the secondary infection
                                             the differentials. Many pruritic patients will also          has occurred. Likewise, whether the pruritus onset was
                                             have secondary infections such as Staphylococcus             acute and intense or chronic and progressive can also
                                             pseudintermedius or Malassezia pachydermatis. These          be telling. Parasitic conditions tend to have an acute
                                             infections may directly cause the pet’s pruritus or          and intense onset whereas canine atopy is a more
                                             intensify the sensation. Regardless, establishing when       chronic and progressive disorder. Finally, the location
                                             they occur with respect to the onset of pruritus or          and nature of associated skin lesions may be helpful. In
                                             whether pruritus remains despite their elimination,          the case of allergic dermatitis, thinned skin and haired
                                             can be helpful in establishing the likely cause. This is     regions (paws, pinnae, perianal, axilla, and inguinal
                                             where the saying “an itch that rashes or a rash that         regions) are normally affected. Alternatively, endocrine
                                             itches” can provide valuable insight. Allergic conditions    or autoimmune conditions tend to be symmetrical, with
                                             tend to be pruritic disorders that get complicated           the face and trunk more frequently affected.
                                             by secondary infections and the patient’s situation

                                                     Once the differentials for the patient have been established and prioritized, the diagnosis
                                                     frequently relies on eliminating potential diagnoses through diagnostics and therapeutic trials.
                                                     The author prefers to work through differential lists in the following manner:

                                                         1. Is there a likelihood that the patient is pruritic for a non-allergic condition?
                                                            a. If so, perform appropriate skin scrapes, blood work, or biopsies
                                                            b. If not, move on to step 2
                                                         2. Are parasites present or highly suspected?
                                                            a.	
                                                               If so, perform diagnostics to confirm their presence or establish an appropriate
                                                               preventative or therapeutic trial.
                                                            b. If not, or parasitic control is adequate move on to step 3
                                                         3. Is the patient’s pruritus seasonal?
                                                            a. Yes, then …
                                                               i. Has the potential for fleas been adequately addressed?
                                                                 1. If not, institute integrated flea control
                                                                 2. If flea control is appropriate, then the patient has atopic dermatitis
                                                            b. No, then…
                                                               i. Start a diet elimination trial
                                                                 1.	If the patient responds, then rechallenge with their prior or normal diet, if pruritus
                                                                     recurs, reinstitute feeding with the therapeutic diet and if clinical signs resolve once
                                                                     again, the diagnostic loop has been closed and a diagnosis of cutaneous adverse
                                                                     food reaction has been established. Pruritus may recur as soon as hours or up to 1-2
                                                                     weeks after reintroducing the pet’s normal diet. To help the pet parent establish a
                                                                     diagnosis as quickly as possible reintroduction of the prior diet, treats, and chews
                                                                     should be done as soon as possible.
                                                                 2.	If the patient fails to respond, the patient is most likely atopic or has concurrent
                                                                    allergic conditions. Start specific or symptomatic therapy for canine atopic
                                                                    dermatitis

                                                     The reason for this approach is that if a non-allergic condition is suspected, those most often
                                                     can be confirmed via blood work or biopsy with histopathology. This provides the pet parent
                                                     with a quick and definitive answer as to those differentials. This is in contrast to that of allergic
                                                     causes, where no single definitive test exists. Nowhere is this more evident than with canine atopic
                                                     dermatitis, which is a diagnosis of exclusion. In cases where a parasite or evidence of parasites
                                                     are found a definitive diagnosis can be made. However, in many cases of allergic dermatitis, the
                                                     differential is either confirmed or excluded by therapeutic trials.

                                             6

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                                             Flea allergy dermatitis should always be considered                          and lamb.4 There are three different concept diets to
                                             a potential or concurrent diagnosis for any dog                              help avoid these offending allergens: novel or exotic
                                             presenting with a history of pruritus. Acute or intense                      protein, hydrolyzed protein, or a home-cooked diet.
                                             pruritus affecting the lumbosacral region, tail base,                        Just as there is no definitive commercial test for CAFR
                                             or caudomedial thighs should raise suspicion along                           in dogs, there is also no definitive diet that is effective
                                             with certain geographic regions where fleas can be                           100% of the time. However, for the purpose of diet
                                             a perennial problem. When fleas are suspected an                             elimination trials, there is currently no commercially
                                             effective flea control program should be initiated. Many                     available over the counter diet that provides an
                                             preventative products are available and effective for                        adequate substitute for a commercial therapeutic
                                             this purpose. It is important to keep in mind the flea                       diet.5 Diet selection should ideally be based on patient
                                             life cycle and your geographic region when considering                       history and dietary needs. A diet elimination trial should
                                             how long a therapeutic trial should be implemented.                          last at least 8 weeks in canine patients to increase the
                                             Regions in the Southeast United States, specifically                         likelihood of properly identifying a CAFR.6 Achieving
                                             Florida, may need a more aggressive approach for this                        this length of time in some patients can be difficult and
                                             differential and consider it a concurrent complicating                       a brief, tapering dose of glucocorticoids can be helpful
                                             factor for any allergic condition compared to other                          during the initial phases of the diet elimination trials.7
                                             regions in the U.S. In addition to fleas, other parasites
                                                                                                                          Canine atopic dermatitis is solely a clinical diagnosis. It
                                             such as Sarcoptes scabiei and Cheyletiella spp. may
                                                                                                                          is a diagnosis of exclusion and in essence is proving a
                                             also cause intense, acute pruritus in any age of patient.
                                                                                                                          negative which contributes to frustration surrounding
                                             These mites on occasion can be difficult to recover
                                                                                                                          the condition. A diagnosis of canine atopic dermatitis
                                             and when suspected may warrant a treatment trial.
                                                                                                                          can be made in patients with seasonal pruritus when
                                             Many of the current flea preventatives are considered
                                                                                                                          fleas have been eliminated, or in non-seasonally
                                             an effective treatment options for these and other
                                                                                                                          pruritic patients when all other allergic and non-
                                             ectoparasties, and when utilized for a flea preventative
                                                                                                                          allergic conditions have been ruled out that directly
                                             program, should be sufficient for ruling out these
                                                                                                                          or indirectly cause pruritus (predispose to secondary
                                             potential pruritic causes.2
                                                                                                                          infections). Although allergy tests exist, they are poorly
                                             Once parasites are eliminated as a potential cause, a                        named and they are not screening, diagnostic, or
                                             cutaneous adverse food reaction should be considered.                        confirmatory in nature.8 No test is completely sensitive
                                             Suspicion for a food allergen being the inciting                             or specific and clinically normal dogs may have positive
                                             cause should increase if the patient has nonseasonal                         reactions, while clinically affected dogs can have
                                             clinical signs, does not respond well to anti-pruritic                       negative results. Allergy tests as currently conducted
                                             medications, has concurrent GI signs, or clinical signs                      in veterinary medicine should only be thought of and
                                             began at a certain age for the patient. No one historical                    utilized as a “guide” for selection of allergens to be
                                             clue is definitive or always indicative of a cutaneous                       included in allergen specific immunotherapy or the
                                             adverse food reaction, but a combination of the                              basis for allergen avoidance measures. Two sets of
                                             preceding historical clues should raise the clinician’s                      clinical criteria known as “Favrot’s criteria” have also
                                             level of concern. Although much effort has been                              been developed to assist with the diagnosis of canine
                                             directed toward the development of a diagnostic test to                      atopy. These sets of criteria should not be used as a
                                             aid in the diagnosis of a CAFR, to date the single most                      sole diagnostic test as they are also not completely
                                             effective diagnostic procedure to identify a CAFR in a                       specific or sensitive for the condition. However, when
                                             patient remains a diet elimination trial with subsequent                     combined with a careful work-up as described above
                                             provocation testing.3 The most commonly identified                           they can enhance a clinician’s diagnostic accuracy.
                                             food allergens in dogs are beef, dairy, chicken, wheat

                                             References                                                                   5. Olivry T, Mueller RS. Critically appraised topic on adverse food
                                             1. Hensel P, Santoro D, Favrot C, et al. Canine atopic dermatitis:              reactions of companion animals(5):discrepancies between
                                                 detailed guidelines for diagnosis and allergen identification. BMC           ingredients and labeling in commercial pet foods. BMC Vet Res
                                                 Vet Res 2015;11:196.                                                         2018;14:24.
                                             2. Parasitic Skin Diseases. In: Coyner KS ed. Clinical Atlas of Canine      6. Olivry T, Mueller RS, Prélaud P. Criticallyappraised topic on adverse
                                                 and Feline Dermatology. 1st ed. Hoboken, NJ:Wiley-Blackwell,                  food reactions of companion animals(1):duration of elimination
                                                 2020; 111-130.                                                                diets. BMC Vet Res 2015;11:225.
                                             3. Mueller RS, Olivry T. Critically appraised topic on adverse food         7. Favrot C, Bizikova P, Fischer N, et al. The usefulness of short-course
                                                 reactions of companion animals(4): Can we diagnose adverse food              prednisolone during the initial phase of an elimination diet trial
                                                 reactions in dogs and cats with in vivo or in vitro tests. BMC Vet           in dogs with food-induced atopic dermatitis. Vet Dermatol 2019;
                                                 Res 2017;13:275.                                                             30:498-e149.
                                             4. Mueller RS, Olivry T, Prélaud P. Critically appraised topic on adverse   8.  DeBoer DJ, Hillier A. THe ACVD task force on canine atopic
                                                 food reactions of companion animals(2): common food allergen                  dermatitis (XV): Fundamental concepts in clinical diagnosis. Vet
                                                 sources in dogs and cats. BMC Vet Res 2016;12:9.                              Immunol Immunopathol 2001;81:271-276.

                                             7

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HILL’S GLOBAL SYMPOSIUM 2021 | PROCEEDINGS
                                             GETTING THE MOST OUT OF THE
                                             TELEDERMATOLOGY CONSULTATION

                                                                           Richard P. Usatine, M.D.
                                                                           Professor, Dermatology and Cutaneous Surgery
                                                                           Professor, Family and Community Medicine
                                                                           Founding Director, Skin Clinic, University Health System
                                                                           University of Texas Health San Antonio, TX, USA

                                             HOW TO PREPARE FOR TELEDERMATOLOGY VISITS                  • S ome viral infections such as mild to moderate zoster
                                             To start doing teledermatology you need appropriate           or herpes
                                             hardware and software with a strong Internet or data       • Monitoring chronic dermatology diagnoses that are
                                             connection. The electronic health record (EHR) on             currently under control
                                             a good quality computer with a standard monitor            By patient characteristics:
                                             is the foundation. In medicine with human patients
                                             the privacy considerations need to be HIPAA (Health        • Y
                                                                                                          oung adults and teenagers that are technology
                                             Insurance Portability and Accountability Act) compliant.     proficient
                                             Communication for telehealth may be as simple as           • Have access to high-quality Wi-Fi connections
                                             a phone conversation or as complex as a discussion         • Don’t need an interpreter
                                             through a HIPAA compliant electronic portal from the       • Follow-up patients well-known to the provider
                                             EHR to a patient portal (e.g. Epic and MyChart).
                                                                                                        Dermatology cases in which teledermatology is most
                                             Software options for telehealth:                           challenging or least effective:
                                             •   Doximity                                               By diagnosis:
                                             •   Zoom
                                                                                                        •   Skin cancer and precancer such as actinic keratoses
                                             •   Doxe.Me
                                                                                                        •   Skin cancer detection and total body exam
                                             •   Patient Portals in EHRs
                                                                                                        •   Systemic dermatologic disease in acute presentation
                                             Examples of telemedicine built into EHRs:1                 •   Immunobullous disease in acute presentation
                                             • AdvancedMD                                               •   Any dermatologic condition with plans for
                                                                                                            
                                             • Allscripts                                                   intralesional injections
                                             • Cerner                                                   •   Rashes or any condition needing biopsies
                                             • Epic                                                     •   Conditions needing cryotherapy
                                             • Salus                                                    •   By patient characteristics:
                                             • PrognoCIS                                                •   Any patient with limited technology literacy (often
                                             Doximity app for phone, tablet and computer: You can            older)
                                             use your cell phone to call patients without revealing     •    Patients without smart phone or computer
                                             your private number. When their phone rings, patients      •    Patients without Wi-Fi or good phone/data
                                                                                                             
                                             see your office number (or any number you designate)            connection
                                             on their CallerID. For video conferencing, just dial the   •    Patients not knowing how to use their smart phone
                                             patient’s number to start a video call. They are sent a          for video connections
                                             text message from a no-reply number (not your cell         •     Patients not using email and not able to send
                                                                                                              
                                             number). With a few taps the patient and provider are            photographs when needed electronically
                                             connected.2
                                                                                                        •     Patients too shy for video conference
                                             Dermatology cases in which teledermatology is most
                                                                                                        What environment is best for teledermatology?
                                             effective:
                                                                                                        • A
                                                                                                           quiet environment on both ends of the
                                             By diagnosis:
                                                                                                          communication
                                             •   Acne                                                   • Good lighting – avoid backlighting and dark rooms
                                             •   Psoriasis
                                             •   Atopic dermatitis
                                             •   Fungal infections that are classic

                                             8

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                                             How to establish rapport with the patient using video?       During the physical exam, tips for best results:
                                             • L ook at the phone or camera to establish eye contact     • G ood lighting which is often indoors rather than
                                             • Place patient’s image near your camera if patient is         outdoors where there may be glare and shadows
                                                on the monitor                                            • Smart phone light or a flashlight can help examining
                                             • Stay focused on patient                                       the oral cavity
                                             • Avoid distractions, disable other alerts, ringers,        • A family member or friend can help point the phone
                                                alarms                                                       or camera at the back or buttocks
                                             • Advise patient when you are looking away at medical       • Foot exam means removing shoes and socks
                                                record or typing notes                                    • Palpation can be done by the patient or parent if
                                             • Dress professionally                                          directions are given clearly
                                             • Avoid eating during visit                                  • Even a partial neurologic exam is possible with clear
                                             • Understand that a patient may not want to reveal             directions
                                                a private area over a video connection even if they       • A ruler or another common object such as a coin can
                                                would feel comfortable with this in the office               be placed near a lesion to give size
                                             • Apologize if you are calling or connecting after the      • Home dermoscopy is possible and may make sense
                                                appointment time and don’t assume that the patient           for patients at the highest risk of melanoma
                                                has nothing else to do but to wait for you                • There is a dermoscopy loan program available
                                             • If you are calling or connecting early make sure the         through Oregon Health Sciences University (OHSU)
                                                patient is ready by asking their permission to proceed    Tips for working with older adults:3
                                                now vs calling back
                                                                                                          • If the patient has decreased hearing, the patient may
                                             • If there is no answer, leave a message that you or
                                                                                                             wear a headset
                                                someone from your office will call back so they know
                                                that the phone number you are using is not spam or        • Provider should use a good microphone or wear a
                                                telemarketing                                                headset
                                             • Use office staff to help facilitate these connections     • Position camera for patients to be able to see and
                                                when using the patient portal of an EMR. Patients            read your lips
                                                may need coaching to figure out how to use the            • Speak slowly and ask patient to teach-back to you
                                                patient portal                                            • Send written instructions electronically or by mail if
                                                                                                             necessary
                                             Steps to increase efficiency in teledermatology:
                                             • U se office staff to schedule the telehealth visits and   Pitfalls in teledermatology:
                                                to schedule follow-ups                                    • Patients who can’t navigate the technology
                                             • Transmit prescriptions electronically including           • Out of focus photos
                                                controlled substances when necessary                      • Unhappy patients when the circumstances require an
                                             • Transmit orders for labs and imaging electronically          in-person visit – the rare patient becomes unhappy
                                                when possible and inform patients how to get these           stating they wasted their time – fortunately this is
                                                tests done                                                   truly rare as patients are usually very grateful for the
                                             • Do verbal health education but consider electronic           teledermatology visit and understand that the next
                                                information sheets/handouts when it is easy to send          step is an in-person visit
                                                an email or use the EMR for messaging.                    Benefits for patients:
                                             How to maintain your own privacy while connecting            • No travel needed
                                             to patients:                                                 • No parking needed
                                             • D on’t call or FaceTime from your personal cell phone     • Avoiding contact with COVID-19
                                                number unless you are prepared to receive messages        • No problems finding the clinic
                                                and phone calls from this patient in the future – in
                                                                                                          • Less time due to no travel and no waiting room time
                                                general it is best to avoid this situation –
                                                                                                          • While waiting for a visit, chores and work can be
                                             • Consider dialing *67 before the number, but this may
                                                                                                             performed
                                                result in the patient not picking up the phone call as
                                                it looks like telemarketing. The app Doximity works       • Helps patients with limited mobility and limited
                                                to avoid this                                                access to transportation
                                             • If you are using a phone-based app such as Doximity,      Risks for patients:
                                                assign the office phone to the phone number that          • Insurance may not cover the visit especially as the
                                                they will see the call coming from                           pandemic becomes less severe
                                             • Have an email address that you can use for patients       • Procedures can’t be performed, so additional visits
                                                to send photographs when needed as these photos              are then needed
                                                are often in better focus than video images
                                             • Don’t text from your private phone or send emails
                                                from your private email address

                                             9

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                                             Benefits for providers:                                                    divide - patients with less money and resources
                                             • C an work from home or possibly a more relaxed office                   get help obtaining high-speed Internet and smart
                                                                                                                        phones/computers/tablets. (note that families often
                                             • Less exposure to COVID-19
                                                                                                                        need this technology for online schooling and work
                                             • Fewer no-shows - especially due to transportation                       at home for adults)
                                                problems
                                                                                                                     • Continue public and private insurance coverage for
                                             • Can do charts while listening to patients without                       telehealth.
                                                appearing rude
                                             • Can reach elderly and underserved patients                            Conclusions:
                                                                                                                     • T here are many benefits to telehealth for patients
                                             Risk for providers:
                                                                                                                        and providers
                                             • Insurance may not pay for the visit, especially phone                • There are some pitfalls regarding limited technology
                                                visits                                                                  literacy and limited access to the hardware and
                                             • Decreased satisfaction when procedures are needed                       Internet
                                                and cannot be performed                                              • Private and public support to improve technology
                                             What can be done to make teledermatology more                              literacy and access to the hardware and the Internet
                                             effective?                                                                 can allow for innovations and growth of telehealth.
                                             • P roviding avenues for patients to learn how to use
                                                the technology needed.
                                             • Federal and state support to overcome the digital

                                             References                                                              5. Clarke EL, Reichenberg JS, Ahmed AM, et al. The utility of
                                             1. https://www.softwareadvice.com/telemedicine/#buyers-guide                teledermatology in the evaluation of skin lesions. J Telemed
                                                                                                                         Telecare 2021:1357633X20987423. doi: 10.1177/1357633X20987423.
                                             2. https://www.doximity.com/app
                                                                                                                         Epub ahead of print. PMID: 33461401.
                                             3. Nieman CL, Oh ES. Connecting With Older Adults via Telemedicine
                                                                                                                     6. Cline A, Kim C, Deitz M, et al. Real-World Direct-to-Patient
                                                 [published online ahead of print, 2020 Aug 11]. Ann Intern Med.
                                                                                                                         Teledermatology in a Low-Income, Elderly Population. J Am
                                                 2020;10.7326/M20-1322.
                                                                                                                         Acad Dermatol 2021:S0190-9622(21)00187-0. doi: 10.1016/j.
                                             Further reading                                                             jaad.2021.01.038. Epub ahead of print. PMID: 33476731.
                                             1. Berman HS, Shi VY, Hsiao JL. Challenges of Teledermatology:         7. Conforti C, Lallas A, Argenziano G, et al. Impact of the COVID-19
                                                 Lessons Learned During COVID-19 Pandemic. Dermatol Online J             Pandemic on Dermatology Practice Worldwide: Results of a Survey
                                                 2020;26:13030/qt7193305r. PMID: 33342172.                               Promoted by the International Dermoscopy Society (IDS). Dermatol
                                             2. Hadeler EK, Beer J, Nouri K. Teledermatology: Improving Access or       Pract Concept 2021;11:e2021153. doi: 10.5826/dpc.1101a153. PMID:
                                                 Widening Healthcare Disparities? J Drugs Dermatol 2020;19:1248.         33614221; PMCID: PMC787
                                                 doi: 10.36849/JDD.2020.5693. PMID: 33346507.
                                             3. Cartron AM, Aldana PC, Khachemoune A. Pediatric teledermatology:
                                                 A review of the literature. Pediatr Dermatol 2021;38:39-44. doi:
                                                 10.1111/pde.14479. Epub 2020 Dec 9. PMID: 33295665.
                                             4. Mizes A, Vainder C, Howerter SS, et al. Access to consultative
                                                 dermatologic care via physician-to-physician asynchronous
                                                 outpatient teledermatology. Am J Manag Care 2021 ;27:30-32. doi:
                                                 10.37765/ajmc.2021.88574. PMID: 33471459.

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HGS_2021_Proceedings Book.indb 10                                                                                                                                                  17/04/21 12:21 PM
HILL’S GLOBAL SYMPOSIUM 2021 | PROCEEDINGS
                                             MULTIMODAL TREATMENT OF ATOPIC DERMATITIS:
                                             THE FOUR MOST IMPORTANT CONCEPTS TO KNOW

                                                                        Douglas J. DeBoer, DVM, DACVD
                                                                        School of Veterinary Medicine
                                                                        University of Wisconsin
                                                                        Madison, WI, USA

                                             A change in our thinking                                         barrier to prevent infections where possible, as
                                             Historically, management of atopic dermatitis (AD)               opposed to recurring cycles of treatment
                                             has been aimed at the end process of the disease, in            • Modification of the immunologic response through
                                             other words, focused on anti-inflammatory therapies.               allergen immunotherapy
                                             “Managing inflammation” has been the first goal
                                             of therapy. This traditional approach was a rather              • Controlling the primary factor in patient discomfort,
                                             blunt instrument often consisting principally of oral              that is, pruritus – and if possible, modifying the
                                             corticosteroids, with antihistamines or fatty acids as             neuro-immunologic ‘vicious cycles’ that contribute to
                                             possible adjuncts. As our understanding grew, we                   chronicity
                                             gained additional tools to manage the inflammation, for         • Managing inflammation, where possible targeting the
                                             example the oral and topical calcineurin inhibitors such           therapy to treat specific signs such as scratching, or to
                                             as ciclosporin; oclacitinib and lokivetmab to manage               treat regionally with topical products.
                                             pruritus; and effective topical corticosteroid products
                                             that could manage inflammation with less systemic               Foundation vs. accessory treatments
                                             effect. We also gained a renewed understanding of               We often say that every dog with AD has one key
                                             the importance of treating secondary complications              “foundation treatment” - one particular treatment that
                                             such as bacterial and yeast infections. All of these            provides the most efficacy for that patient, and the
                                             approaches, even as they evolved, were still completely         best client satisfaction. This treatment is often a drug
                                             reactive – reacting to the inflammatory process, after it       or biological, at least initially. Current treatments that
                                             had already become well-established in the skin.                fall into this group include corticosteroids, ciclosporin,
                                                                                                             oclacitinib, lokivetmab, and allergen immunotherapy.
                                             Our newer approach to long-term treatment of AD
                                                                                                             The best foundation treatment DOES vary from patient
                                             encompasses a broader, whole-patient view, stressing
                                                                                                             to patient, and situation to situation. Things to think
                                             a multifaceted protocol, based on a multifaceted
                                                                                                             about when choosing and using foundation treatments
                                             pathogenesis, and multifaceted clinical signs that are
                                                                                                             include:
                                             likely different in each patient. In addition, where possible
                                             we now stress a proactive approach to treatment – in            • Efficacy – of course. Each of the above foundation
                                             other words, correcting the underlying pathogenesis                treatments will probably work well for somewhere
                                             of the disease where possible, preventing acute flares             between 60-80% of dogs.1-4 However, it’s not the
                                             where we can, and forestalling the development of                  same 60-80% for each treatment! Unfortunately,
                                             chronic inflammatory changes in the skin that become               at this point, there is no way to predict in advance
                                             much more difficult to reverse. Important elements of              which treatment will turn out to be the best one for
                                             this new approach include:                                         a particular dog. This implies that trial-and-error is
                                                                                                                a necessary part of early treatment and clients must
                                             • Elimination of allergens where possible (decreasing
                                                                                                                understand this.
                                                allergen load), targeting environmental, parasitic,
                                                dietary, and microbial allergens                             • Administration and adherence – what does the owner
                                                                                                                prefer; what is easy for them to do?
                                             • Augmenting or repairing the epidermal barrier in an
                                                attempt to limit percutaneous penetration of allergens       •
                                                                                                              Owner preferences; for example the biological
                                                and irritants                                                 treatments may resonate more with some owners
                                                                                                              than others.
                                             • Control of secondary infections when and as they
                                                occur, and augmenting the epidermal antimicrobial            • Adverse effect profile of each treatment.

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                                             • Safety, contraindications, and comorbidities for each        • Nutritional considerations: beyond being a source of
                                                treatment.                                                      EFA supplementation, modern “skin benefit” diets
                                                                                                                often contain other ingredients that may enhance
                                             • The “targetedness” of each treatment – see below for
                                                                                                                barrier function and reduce inflammation, thereby
                                                more about this!
                                                                                                                adding to relief at least by reducing other medication
                                             • Overall cost of the treatment – recognizing that this           requirements. Evidence for efficacy of these diets
                                                includes not only the cost of the treatment itself              is limited at this point, but it does exist - both in
                                                per year, but also recommended monitoring and re-               cutaneous models and in clinical feeding trials.9-11
                                                examination costs.
                                                                                                             •
                                                                                                              Don’t forget the ears! Atopic otitis externa is
                                             With canine AD, one treatment alone typically does               common as part of AD, and for some dogs is a major
                                             not provide optimal relief. Along with finding the best          manifestation of the disease. It may deserve specific
                                             foundation treatment for each pet, adjunct treatments            attention if present.
                                             are enormously helpful for most dogs, both for
                                                                                                             • Antihistamines: there is still virtually no evidence that
                                             increasing efficacy and decreasing amounts of other
                                                                                                                they are beneficial in AD that is of substantial severity,
                                             medications that may be required. So – what works?
                                                                                                                however, they are often tried as “add-ons” for patients
                                             Here are some things to think about:
                                                                                                                with mild disease.
                                             • Parasite and infection control: many dogs with AD
                                                                                                             The concept of targeting
                                                will have concurrent flea sensitization. Thus, routine
                                                prophylactic antiparasitic treatment is advised for          Our recent understanding of the pathogenesis of
                                                all canine AD patients. Very importantly, most dogs          AD stresses that it is an immensely complex process
                                                with AD are very susceptible to secondary infection          involving many different cell types, inflammatory and
                                                with both staphylococci and yeast organisms.                 immunologic processes, cytokines and chemokines,
                                                Treatment must focus on not only initial elimination         and other inflammatory mediators. In particular, many
                                                of the infections, but prevention of future episodes of      of these processes are orchestrated via networks of
                                                infection.                                                   cytokines. Exactly which cells, processes, and mediators
                                                                                                             are responsible for clinical signs and patient discomfort
                                             • Topical treatment: bathing helps! Studies have shown         likely varies by individual and by stage of disease.
                                                that frequent (weekly to twice weekly) bathing with
                                                any non-irritating, emollient shampoo can have a             In parallel with this concept we must recognize that
                                                limited antipruritic effect;4 it also washes away debris,    foundation treatments vary greatly in how targeted
                                                environmental allergens, and organisms from the skin.        they are with respect to, for example, cytokine networks
                                                In human AD, application of emollient preparations           (Table 1). Corticosteroids are very untargeted, in that
                                                to the skin is an important and basic element                they affect production of many cytokines by many cell
                                                of treatment, and unquestionably helps relieve               types. This is why they work so well, but also why they
                                                symptoms over time. Topical modification of barrier          have adverse effects. Ciclosporin is more targeted, and
                                                function is an active area of research in veterinary         oclacitinib even more so. The most targeted treatment
                                                medicine. Initial research has shown that application        we have currently is lokivetmab, which affects only a
                                                of topical lipid preparations can result in improvement      single cytokine.
                                                of the intercellular lipid lamellar structure and            Putting these two concepts together: a dog with
                                                composition and can be associated with limited               relatively early, uncomplicated AD with minimal lesions
                                                clinical improvement, though such improvement                and mild to moderate pruritus may be simpler to address
                                                typically takes months.5,6                                   than a dog with severe pruritus, longstanding disease,
                                             • Essential fatty acid (EFA) supplementation – via diet        secondary complications, and chronic skin changes. The
                                                or otherwise: EFA supplements remain a cornerstone           latter patient may have dozens of cytokines wreaking
                                                of conservative management. Their effects may occur          havoc. In this case, is it fair or reasonable to expect
                                                through their weak anti-inflammatory actions, through        that a very targeted therapy will be effective? It may
                                                possible effects on epidermal barrier function, and          be, or it may not be – and if it is not, the reason might
                                                most importantly through their medication-sparing            be that it is simply too targeted for that patient at that
                                                effects.7,8 Because they are relatively inexpensive, safe,   time. Moving up towards something LESS targeted may
                                               and easily administered, many dermatologists advise           provide a solution in this instance. Once the condition is
                                               that, ideally, all atopic pets should receive enhanced        better controlled, moving back down to more targeted
                                               levels of EFA in their diet. Typically, daily doses in the    treatments may provide long-term benefit with a better
                                               range of 40-100 mg/kg of omega-3 anti-inflammatory            adverse effect profile.
                                               fatty acids, administered via supplement or as part of
                                               the dietary formulation itself, are recommended to
                                               achieve this benefit.

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HILL’S GLOBAL SYMPOSIUM 2021 | PROCEEDINGS
                                                  TABLE 1.
                                                  Extent of cytokine “targeting” of common foundation treatments in canine atopic dermatitis,
                                                  listed from least to most targeted.

                                                   TREATMENT             TARGETED?                       COMMENTS
                                                                                                        Reduce production of many cytokines at the DNA
                                                  Glucocorticoids        Untargeted
                                                                                                        transcriptional level

                                                                                                        Blocks transcription of several cytokine genes in activated
                                                  Ciclosporin            Somewhat targeted
                                                                                                        T-lymphocytes, such as IL-2
                                                                                                        Blocks cytokine receptor function mainly for interleukin-31;
                                                  Oclacitinib            Somewhat targeted              lesser effects on some other cytokines such as interleukins 2, 4,
                                                                                                        6, and 13

                                                  Lokivetmab             Completely targeted            Binds and inactivates only interleukin-31

                                             Short term plan, long term plan                                              clinical remission. Fast-acting “foundation treatment”
                                             Practice guidelines for treatment of AD4 stress that                         drugs are often the mainstay here. The “long term
                                             one approach or set of therapies is appropriate for                          plan” is very different. It is intended to maintain clinical
                                             short-term or immediate management of clinical flares,                       remission after it is induced. Elements of the “long term
                                             and a second set is used in an attempt to gain longer-                       plan” are often accessory treatments like nutrition and
                                             term control of the disease. Owners, especially, need                        topical measures, and they will take perhaps months
                                             to understand this principle: “the therapy we use will                       to make a difference. Their effects will be more subtle,
                                             change over time.” What we treat your dog with initially                     and will likely mostly manifest in better overall control
                                             will differ from what we will recommend over the long                        with fewer relapses, along with less requirement for
                                             term. The “short term plan” is designed to provide                           foundation treatment drugs.
                                             immediate relief of the acute disease and induce

                                             References
                                              ote to the reader:
                                             N                                                                             6. Popa I, Remoue N, Osta B, et al. The lipid alterations in the stratum
                                             The International Committee on Allergic Diseases of Animals (ICADA)              corneum of dogs with atopic dermatitis are alleviated by topical
                                             regularly publishes expert panel reviews, updates, and practical                 application of a sphingolipid-containing emulsion. Clin Exp
                                             guidelines for treating allergic diseases in dogs and cats. Many                 Dermatol. 2012;37:665-671.
                                             helpful references can be accessed through the ICADA website at               7. Saevik BK, Bergvall K, Holm BR, et al. A randomized, controlled
                                             www.icada.org.                                                                   study to evaluate the steroid sparing effect of essential fatty acid
                                                                                                                              supplementation in the treatment of canine atopic dermatitis. Vet
                                             1. Little PR, King VL, Davis KR, et al. A blinded, randomized                    Dermatol. 2004;15:137-145.
                                                clinical trial comparing the efficacy and safety of oclacitinib and
                                                                                                                           8. Müller MR, Linek M, Löwenstein C, et al. Evaluation of cyclosporine-
                                                ciclosporin for the control of atopic dermatitis in client-owned
                                                                                                                              sparing effects of polyunsaturated fatty acids in the treatment of
                                                dogs. Vet Dermatol. 2015;26:23-30, e7-8.
                                                                                                                              canine atopic dermatitis. Vet J. 2016;210:77-81.
                                             2. Gadeyne C, Little P, King VL, et al. Efficacy of oclacitinib (Apoquel®)
                                                                                                                           9. Watson AL, Fray TR, Bailey J, et al. Dietary constituents are able
                                                compared with prednisolone for the control of pruritus and clinical
                                                                                                                              to play a beneficial role in canine epidermal barrier function. Exp
                                                signs associated with allergic dermatitis in client-owned dogs in
                                                                                                                              Dermatol. 2006;15:74-81.
                                                Australia. Vet Dermatol. 2014;25:512-8, e86.
                                                                                                                          10. van Beeck FL, Watson A, Bos M, et al. The effect of long-term
                                             3. Moyaert H, Van Brussel L, Borowski S, et al. A blinded, randomized
                                                                                                                              feeding of skin barrier-fortified diets on the owner-assessed
                                                clinical trial evaluating the efficacy and safety of lokivetmab
                                                                                                                              incidence of atopic dermatitis symptoms in Labrador retrievers.
                                                compared to ciclosporin in client-owned dogs with atopic
                                                                                                                              J Nutr Sci. 2015;4:e5.
                                                dermatitis. Vet Dermatol. 2017;28:593-e145.
                                                                                                                          11. Witzel-Rollins A, Murphy M, Becvarova I, Werre SR, Cadiergues
                                             4. Olivry T, DeBoer D, Favrot C, et al. Treatment of canine atopic
                                                                                                                              MC, Meyer H. Non-controlled, open-label clinical trial to assess
                                                dermatitis: 2015 updated guidelines from the International
                                                                                                                              the effectiveness of a dietetic food on pruritus and dermatologic
                                                Committee on Allergic Diseases of Animals (ICADA). BMC Vet Res.
                                                                                                                              scoring in atopic dogs. BMC Vet Res. 2019;15:220.
                                                2015;11:210-221.
                                             5. Marsella R, Segarra S, Ahrens K, et al. Topical treatment with
                                                SPHINGOLIPIDS and GLYCOSAMINOGLYCANS for canine atopic
                                                dermatitis. BMC Vet Res. 2020;16:92-97.

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HGS_2021_Proceedings Book.indb 13                                                                                                                                                           17/04/21 12:21 PM
HILL’S GLOBAL SYMPOSIUM 2021 | PROCEEDINGS
                                             HOCUS-POCUS VETERINARY DERMATOLOGY:
                                             CURTAIN LIFTED AND MYTHS REVEALED!

                                                                        Christina Restrepo, DVM, DACVD
                                                                        Naples, FL, USA

                                             Myth 1: Atopic Dermatitis (AD) and Cutaneous                  Elimination diet trials are required for patients with
                                             Adverse Food Reactions (CAFR) are diagnosed by                perennial pruritus and/or concurrent gastrointestinal
                                             utilizing serum and saliva allergy tests.                     signs.1 Once a clinical diagnosis of canine AD is made,
                                             The best and most accurate method of debunking                allergy testing can be performed to identify potential
                                             the above statement is to refer to the ample current          causative allergens for allergen-specific immunotherapy
                                             evidence-based veterinary literature. A sub-group             (ASIT).1 Allergy testing can be performed by IDT and
                                             of the International Committee for Allergic Diseases          ASIS. Neither test is recommended as a screening test
                                             in Animals (ICADA) developed, based on extensive              and should only be used to confirm the clinical diagnosis
                                             searches in online citation databases and abstracts from      of canine AD.1 However, several factors may play a role
                                             international meetings, a set of practical guidelines         in the decision-making as to whether an allergy test
                                             that can be used to assist practitioners in the diagnosis     is necessary. Severe clinical signs, duration of clinical
                                             of canine Atopic Dermatitis (AD).1 These guidelines           signs for more than 3 months per year, insufficient
                                             provide an overview of the diagnosis of canine AD that        management with symptomatic therapy, side effects
                                             involves three distinct, but complementary, approaches.       with symptomatic drug therapy, and, most importantly
                                             These are:1                                                   in my opinion, a willing and financially committed
                                                                                                           owner, justify in most cases, proceeding with allergy
                                             1.	Ruling out of other skin conditions with clinical signs   testing and ASIT. Although IDT is considered the
                                                 that can resemble, or overlap with canine AD.             preferred diagnostic method among dermatologists,
                                             2.	Detailed interpretation of the historical and clinical    ASIS has several advantages over IDT, such as: minimal
                                                features of the condition. The application of clinical     patient risk (no sedation required), less traumatic (no
                                                criteria known as “Favrot’s criteria.”                     repeated skin injections required), more convenient (no
                                                                                                           hair clipping needed, less time-consuming), and lower
                                             3.	Assessment of skin reactivity by IntraDermal Testing      risk of drugs interfering with test results (ie. concurrent
                                                (IDT) (figure 1) or detection of IgE by Allergen-          anti-inflammatory/antipruritic therapy). However, ASIS
                                                Specific IgE Serology (ASIS) testing.                      only measures circulating allergen-specific IgE, does
                                             Figure 1. Canine Intradermal Test                             not take into account other allergic pathways and often
                                                                                                           shows positive reactions in non-allergic dogs.
                                                                                                           IDT and ASIS are still lacking standardization and it is
                                                                                                           suspected that false positive and false negative results
                                                                                                           do occur. It is estimated that between 10 and 30% of
                                                                                                           dogs with a clinically confirmed canine AD may show
                                                                                                           a negative IDT.1 This high percentage of false negative
                                                                                                           results can be due to several factors including improper
                                                                                                           technique, too low test concentration of allergens, drug
                                                                                                           interference, intrinsic host factors, incorrect selection
                                                                                                           of allergens, IDT performed too long after (>60 days)
                                                                                                           or during the peak allergy season, and presence of a
                                             Use of any one of these approaches in isolatizon can          condition called atopic-like dermatitis.1 Canine atopic-
                                             result in misdiagnosis, so it is important not to rely        like disease is clinically identical to canine AD, but IgE
                                             on any of them as a sole diagnostic principle.1 ICADA         response to environmental or other allergens cannot be
                                             concluded that the diagnosis of canine AD is based on         documented. Both testing methods are very different
                                             meeting clinical criteria and ruling out other possible       and not standardized, which inevitably results in
                                             causes with similar clinical signs. Flea combing, skin        poor correlation between both tests. Currently many
                                             scraping and cytology should be performed, where              companies are offering allergen-specific serology
                                             necessary, as part of a thorough work-up (figure 2).          testing, but a study showed test results do not agree
                                                                                                           well between laboratories.1 Nonetheless the success
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