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Home , Allergies in cats, Cheyletiella, Demodicosis, Edema

FELINE DERMATOLOGY

Karen L. Campbell, DVM, MS, DACVIM, DACVD Professor Emerita, University of Illinois Clinical Professor of Dermatology, University of Missouri Evaluation of the Pruritic Itching is a PAIN

• Parasites • • • Neurogenic Parastic causes of feline itching

• • gatoi • Demodex cati • Notedres • • Otodectes • Mosquitoes • Ticks Fleas

• May be difficult to find on • Check fecal – fleas or tapeworms present? • Manifestations include pruritus, symmetrical hair loss, miliary , eosinophilic complex • Treatment trials • Serum IgE to saliva • IDT flea reactivity Feline

• Demodex cati • Demodex gatoi Demodex gatoi

• Short bodied • Found in the stratum corneum • Contagious • Pruritic • May find on scrapings or fecal flotation Demodex gatoi

• Distribution • Head, neck, elbows • Ventral • Clinical signs • Alopecia • Scale, erythema • Excessive grooming Demodex gatoi

Therapy • Stop any glucocorticoid or tx • Treat all in-contact • Lime sulfur is tradional treatment of choice • improve in 3 weeks • treat for 4-6 weeks minimum • Bravecto for cats: one treatment may be curative • : 300 mcg/kg once weekly, variable response • Advantage Multi (q 7-14 days, variable response) • Amitraz: 125 ppm (1/2 normal strength) Demodex cati

Localized follicular demodicosis • Rare condition • , periocular, head, neck • Differential for feline acne • Usually responsive to lime sulfur or other mild parasiticides • Often self-limiting Demodex cati

Generalized follicular demodicosis • Very rare • Siamese and Burmese at risk • Usually have an underlying condition • FIV, FeLV, Diabetes Mellitus, Bowen’s disease Demodex cati

Treatment: generally much easier than K9 • Manage pyoderma • Lime sulfur dip weekly • Ivermectin 300 mcg/kg wkly + Lime sulfur dips • Bravecto for cats should be curative • Amitraz at 125 ppm (1/2 strength) Cheyletiella: “Walking Dandruff”

• Large, surface dwelling

• Highly contagious, poorly host specific (zoonotic)

• 3 species • C. yasguri • C. blakei Cats • C. parasitivorax Cheyletiella - Pathogenesis

• Non-burrowing mite, lives on skin surface and occasionally pierces skin to feed

• Entire life cycle (21 days) takes place on one host

• Females may survive in environment for 10 days

• Disease prevalence decreasing due to increased use of flea preventatives Cheyletiella – Clinical Signs • Dorsal distribution • Scale • Variable pruritus (possible hypersensitivity in severely pruritic animals) • Exfoliative erythema • Miliary dermatitis or “fur mowing” in cats Cheyletiella - Diagnosis

• Visualization of parasite: • Larger than sarcoptes • Prominent mouth hooks • Visualization of eggs: • Small and attached to hair by fine strands (vs large louse nits firmly cemented to hairs) Cheyletiella Cheyletiella - Diagnosis

• Methods of parasite visualization: • Direct examination of “walking dandruff” (naked eye or hand lens) • Superficial skin scrape • Acetate tape preparation • Fecal floatation • Flea combing • Vacuum test Cheyletiella

• Treatment • All in-contact animals • Minimum of 6 weeks (ideally 2-4 weeks past clinical cure) • Treat environment (pyrethrin spray) • Keratolytic shampoo Treatment

• Lime Sulfur: • Dip weekly for 6 weeks • Fipronil: • 0.25% spray: 1-2 pumps/lb q 2 weeks for 3-4 treatments • 10% spot on: apply 1-2 times/month for 3 treatments • : • Apply once q 2 to 4 weeks for 3 treatments Otodectes cynotis – “Ear Mites”

• Highly contagious, especially in young animals • Not species specific • Cause of >50% of all feline ear disease • 5% of canine ear disease • Asymptomatic carriers are common Otodectes cynotis Complete 3 week life-cycle on a single host Feed/breed in canal • Irritates tissues • Increased cerumen • Mechanical damage • “Coffee ground” debris Migrate all over body • tail base pruritus • miliary dermatitis Otodectes cynotis

Diagnosis • Visualization of mites (otoscopy) • Mineral oil prep of debris • Diff-Quick prep of debris for concurrent infections • Response to therapy Otodectes cynotis - Treatment

• Treat all in contact animals

• Ear Cleaner

• Topical or systemic parasiticide Parasites as causes of scaling • Lynxacarus radovsky = cat fur mite • var canis • Notoedres cati • Felicola subrostratus Feline

• Notoedres cati

• Transient infestation of other animals (foxes, dogs, rabbits, )

• Highly contagious Feline Scabies

• Large numbers of mites are present (easily found on skin scraping) • Die rapidly off host • Smaller than S. scabiei with a dorsal anus (vs terminal anus in S. scabiei) Notoedres: Clinical Signs

• Intense pruritus • Distribution: • Medial pinna • Upper ear, face, eyelids, neck • Feet and perineum • Lesions: • Erythematous papule (early) • Thickened, folded skin with extensive yellow crust (chronic) • Excoriations Notoedres - Diagnosis

• Clinical signs are strongly suggestive • DDX: Pemphigus, Otodectes, Sarcoptes, Cheyletiella, dermatophytosis, atopy, , , . • Positive skin scrape is diagnostic, mites are easily recovered Notoedres – Topical Treatment

• Clip hair NOTE: Permethrin is toxic to cats!!

• Keratolytic shampoo

• Lime sulfur dip • Weekly for 6-8 weeks

• Amitraz: • Increased toxicity in cats Notoedres – Systemic Treatment

• Ivermectin: • 200-300 ug/kg SQ every 2 weeks for 3 treatments • Advantage Multi or Selamectin: • Q 2 weeks for three treatments • Bravecto • One dose should be effective Bite Hypersensitivity

• Erythema, , • Keep cats indoors crusting, hair loss, especially at dusk and depigmentation dawn • ointment or oral • Lesions may be pruritic • Topical/oral steroids and/or painful • May affect nose, ear pinnae, chin, eyelids, and/or footpads • Primarily affects outdoor cats during summer months From Clinicians Brief Allergies in cats

TYPES OF ALLERGIES • Parasitic • Food • Environmental • “” • Contact • Drug Allergies in Cats

• Manifestations include

• Pruritus • Feline Miliary Dermatitis • Eosinophilic Granuloma Complex • Feline Symmetrical Alopecia Facial Pruritus

• Prior to diagnosis of allergies rule out • Otodectes • Demodicosis • Notedres • Viral/mycoplasma infections • Facial pruritus is most commonly associated with food allergies Feline Miliary dermatitis

• Lesions • Variably Pruritic • Papulo-Crustous Eruptions • Location • Dorsum • Neck Feline Miliary Dermatitis Feline Miliary Dermatitis

• Etiologies • Ectoparasites • Allergies (often flea , also food allergies and environmental allergies) • Bacterial (usually 2o) • Dermatophytes (rare presentation) • Autoimmune (pemphigus) • Nutritional deficiency? Feline Miliary Dermatitis

• Diagnostic workup • Examine for parasites • Woods light exam • DTM culture • Cytology (organisms? acantholytic cells? • Treatment trial • Flea control • if responds continue flea control • Evaluate for allergies • Diet trials • Intradermal allergy testing • Biopsy lesions Eosinophilic Granuloma Complex

Three Syndromes Seen • Indolent Ulcers • Eosinophilic Plaques • Linear Common Features • Chronic • Circumscribed • Inflammatory Lesions Eosinophilic Granuloma Complex

• Diagnosis of underlying cause • History • Physical exam • Response to flea control • Restrictive diet trial • Intradermal allergy test • Skin Biopsies (rule out infections and neoplasia) Indolent Indolent Ulcer

• More common in females between 5-6 years • Lesion • Ulcer on upper lip • Often bilateral • May have oral ulcers Indolent Ulcers Indolent Ulcer

• Histopath • hyperplastic with PMN, plasma cell, mononuclear cell infiltration • Differential Diagnosis • Squamous Cell Carcinoma • Fibrosarcoma Indolent Ulcer

• Treatment • Identify and treat underlying cause • Flea control for flea allergies • Change diet • Environmental allergy control • Desensitization treatment • • Convenia or Clavamox • Systemic corticosteroids • Prednisolone 1mg/kg/day • DepoMedrol 5mg/kg/IM • Cyclosporine • 7 mg/kg/day Indolent Ulcer

• Refractory/Recurrent

• Tacrolimus topically

• CO2 laser • Radiation treatment • Cryosurgery Eosinophilic Plaques Eosinophilic Plaque

• More Common in Females • Mean Age 3 Years • Lesion • well-circumscribed • raised • ulcerative plaque Eosinophilic Plaque

• Locations • abdomen • back • legs • head • neck Eosinophilic Plaque

• Histopath • Eosinophilic and infiltration Eosinophilic Plaque

• Diagnostic W/U for EGC • Flea control • Restrictive diet trial • Intradermal allergy test • Biopsy Eosinophilic Plaque

• Treatment • Identify and treat underlying cause • Flea control • Diet change • Environmental allergy control • Desensitization • Elizabethan collar or sweater (to stop self-trauma) • Antibiotics • Corticosteroid trial • Cyclosporine and/or tacrolimus Linear Granuloma

• Either Sex • 1-5 years in age • Lesion • Linear plaque on the posterior aspect of hind legs • Less often found on chin or in mouth • Histopath • necrobiosis of collagen with histiocytic and multinuclear infiltration with or without eosinophils • Usually secondary to allergies, however must rule out inflammatory/infectious/neoplastic diseases Linear Granuloma Linear Granulomas Linear Granuloma

• Treatment • Observation • Identify and treat underlying cause • Flea control • Diet change • Environmental allergy control • Desensitization • Antibiotics • Corticosteroid trial • Tacrolimus or cyclosporine Allergies in Cats

• Common manifestations include • Pruritus +/- crusts/scales • Feline Miliary Dermatitis • Eosinophilic Granuloma Complex • Feline Symmetrical Alopecia Allergies

Pruritus Allergies

Most common Clinical sign is “Overgrooming” Allergies

Food allergy

Flea allergy

Feline Atopy (Environmental) Food Allergies in Cats

• Severe pruritus • Head/neck • Erythema, papules, plaques • externa • +/- concurrent GI signs • Vomiting, diarrhea, increased frequency of defecation • Miliary dermatitis • Eosinophilic dermatitis Prevalence of food allergies

• 0.22 to 6% of cats with dermatologic signs • 17 to 22% of cats with GI signs • Cats mean age 4-5 years (range 3 mo to 11 yr) Immunology

• May involve Types I (IgE), III, or IV • Implications of a variety of immunological reactions • manifestations of food allergies are highly variable • variable onset of signs post-eating • Diagnosis is complicated (serum/skin allergy testing for Type I reactions inadequate) Serum IgE and/or IgG testing for Diagnosis of Food Allergies (dogs) • Veterinary Immunology & Immunopathology 2012; 145:582-589

Specific IgE Specific IgG PPV (%) 15.4 34.8 NPV (%) 80.7 83.7 Definitive Diagnosis of Food Allergy

• Symptoms resolve with dietary change • Symptoms recur with provocation Food

• Heat stable glycoproteins with molecular weights > 10 kDa (and <100 kDa) • Most common food allergens for cats based on studies totaling 78 food allergic cats: • (18%), fish (17%), chicken (5%), (4%), corn (4%), dairy (4%), lamb (3%) and others (single cases) – egg, barley, Cross-reactions (studied in dogs) • Beef, lamb and cow’s milk – affected dogs have antibodies to bovine IgG (Bos d 7) in beef muscle and cow’s milk, cross reacts with ovine IgG • IgG is a major in cow’s milk and beef • Another allergen in beef is phosphoglucomutase, this is also found in lamb and is another source of cross-reactivity between beef and lamb • Other allergens in beef: bovine serum albumin (Bos d6) (also present in milk) – few dogs react to this (more common allergen in people) • Other allergens in milk: alpha-lactalbumin (Bos d 4), beta-lactoglobulin (Bos d 5), casein (Bos d8) Hydrolyzed diets

• IgE reactions triggered by glycoproteins with molecular weights of 10 to 70 kDa • Soy allergic dogs had 60% reduction in pruritus on hydrolyzed soy diet • Corn allergic dogs had 80% reduction in pruritus on hydrolyzed corn diet • Chicken allergic dogs – no reactions to hydrolyzed feather diet, 40% reacted to hydrolyzed chicken with increased pruritus • Hydrolyzed diets should only be fed to dogs/cats suspected as not being allergic to the parent protein Royal Canin Hydrolyzed protein diets

Royal Canin Ultamino (feline) • Starch, feather hydrolysate*, oils, chicory pulp & other prebiotics, vitamins, minerals * By-Products • DNA tested found only granule-bound starch synthase 1 which has not been reported as an allergen for dogs or cats • Over 2000 samples tested without finding protein contaminates • Vet Sci 2018: June 26; 5(3) Royal Canin HP diets (feline) • Brewers rice, hydrolyzed soy protein, chicken fat, beet pulp, prebiotics, vitamins, minerals Royal Canin Multifunction Urinary + Hydrolyzed Protein Dry (feline formula)

• Low RSS (relative supersaturation) • SO index minimizes formation of struvite and calcium oxalate crystals • Brewers rice, hydrolyzed soy protein, chicken fat, chicory, fish oil, vitamins and minerals Duration of diet trials

• Recommendations have ranged from 3 to 16 weeks • 90% of cats with adverse food reactions have remission of clinical signs by 8 weeks • 80% of cats have remission by 6 weeks OTC Limited Ingredient diets? German study of 10 OTC limited-ingredient diets advertised for food-allergic pets found non-declared in 9/10 (Veterinary Dermatology 2017; 28:373-e86)—these included • One rabbit diet contained chicken, turkey, beef, lamb, pork DNA • One vension diet contained chicken, beef, lamb & pork DNA • Another diet contained beef, lamb & pork DNA • Two horse diets contained beef & pork DNA Italian study of 11 diets advertised as single protein source found BONES of other species (avian, fish, mammalian) in 10/11 of the diets (J Anim Physiol Anim Nutr (Berl) 2013 May; 97 Suppl 1:32-8) • Only one fish diet contained only fish! • Duck, rabbit, venison, horse, lamb and another fish diet each contained more than one type of bone fragments (verified via PCR) Allergies in Cats • Atopic Dermatitis-- Diagnosis • R/O ectoparasites • R/O food allergies • R/O infections • Investigate for “offending” allergens • Serum IgE testing • Intradermal testing Pitfalls which Limit Usefulness of Serum IgE testing • Poor reproducibility • Poor specificity for IgE • Many false positives • non-specific binding • Little distinction between positive tests in normal and allergic cats • Great seasonal variability • half-life of serum IgE = 2.5 days • Not all reactions are IgE mediated Intradermal allergy testing

• Evaluates antigen-specific IgE and/or IgGd bound to mast cells in skin but not a perfect test (still have false + and false -) • Cat reactions can be more difficult to read (0.2 ml/kg of 2% Evans blue dye IV prior to test) Treatment Options for Feline Atopy

• Control secondary • Skin barrier repair infections • Omega 3 fatty acids • Eliminate ectoparasites • Antihistamines • Lime Sulfur dips • Seresto collar • Corticosteroids • Revolution • Cyclosporine • Advantage Multi • Oral • Bravecto for cats • Injectable? • Allergen-specific • Oclacitinib? immunotherapy • Maropitant? • Subcutaneous • oral • Gabapentin? Skin Barrier Repair

• Defects in skin barrier allow increased percutaneous absorption of allergens • For repair apply once a week for 4-8 weeks then q 14 days for maintenance Omega 3 fatty acids for cats

• Reduce production of inflammatory mediators • May take 8-12 weeks for full effect • May be synergistic with other treatments to enable use of lower doses of steroids, antihistamines and CsA Antihistamines for cats

• Chlorpheniramine • 2 mg/cat q 12-24 h • (Zyrtec) • 2.5-5 mg/cat q 24 h • Hydroxyzine • 5 mg/cat q 12 h • Loratidine • 5 mg/cat q 12 h • Amitriptyline • 2.5-5 mg/cat q 24 h Corticosteroids for cats • Prednisolone • 1.1-2.2 mg/kg q 24 h for first 2 wks then q 48 h and taper to 0.5 mg/kg • • 0.1-0.2 mg/kg q 24 h for first 2 wks then q 48-72 h and taper to 0.05 mg/kg • If use for > 2 months monitor serum fructosamine Cyclosporine in Cats

• Calcinurin inhibitor • Precautions • Do not use in FeLV or FIV + cats • Indoor cats only and avoid feeding raw meats • Feline dose for treatment of pruritus is 7 mg/kg PO once daily until itching is controlled and then q 48 h • ?? 2.5 mg/kg SQ once daily (?? q 48 h) • May want to monitor serum concentrations, trough level of 250-500 ng/mL recommended Oclacitinib in Cats

• Janus kinase inhibitor • Decreases production of IL-31 • At higher doses may cause bone marrow suppression • Precautions • Do not use in FeLV or FIV + cats • Indoor cats only and avoid feeding raw meats • Half-life is shorter in cats than dogs – may require long-term q 12 hour dosing • Published study following K9 protocol • 5/12 non-flea, non-food allergic cats had good response Maropitant

• Recommended dose for treatment of pruritus in cats is 1-2 mg/kg PO q 24 h • May have increased efficacy when combined with chlorpheniramine 2 mg/cat q 12-24 h Gabapentin for cats

• 10-15 mg/kg q 12 h • ½ 100 mg capsule mixed with canned food • ½ 100 mg capsule opened mix with dry food in ziplock bag “shake and feed” • Commercial liquid contains xylitol (better to have compounded) • Reduce dose if too sleepy

AVOID USE of Progesterone & Related Drugs

• Have potent anti- inflammatory and behavioral modifying effects in cats • Also have very high potential for adverse side effects especially with long term use Progesterone Compounds

• Side effects in cats • Mammary changes • Fibroadenomatous hyperplasia • Papillary adenocarcinoma • Uterine Changes • Cystic endometritis • Pyometra Progesterone Compounds

• Carbohydrate Effects • Hyperglycemia • Hyperlipidemia • Hyperinsulinemia • Impaired glucose tolerance • Diabetes mellitus • Elevated growth hormone • acromegaly Progesterone Compounds

• Effects on the Pituitary Adrenal Axis • Suppresses ACTH production • Other Effects • Decreased spermatogenesis and fertility • Suppression of fibroblasts • T-cell suppression • Cystic mucinous hyperplasia • gallbladder • lightening of the haircoat • Cutaneous xanthomatosis Facial Pruritus

• Parasitic • Otodectes • Demodicosis • Notedres • Allergic • Food • Environmental • Inflammatory • Viral/mycoplasma infections • Feline acne • Dermatophytes • Neurogenic • May be component of herpesvirus infection Feline Viral and Mycoplasma Induced Facial Pruritus

• PCR testing now readily available • Recent vaccination may cause “false” positive— I treat and retest Feline Viral and Mycoplasma Induced Facial Pruritus

• Viral: alpha-interferon 1000 IU/day • Viral: famciclovir 62.5 mg/cat (1/2 of 125 mg tablet) for 3 weeks • Mycoplasma: pradofloxacin 7.5 mg/kg (monitor CBC q 7 days) OR • Mycoplasma: doxycycline 2.5-5 mg/kg q 12 h with water chaser Other Inflammatory Causes of Feline Pruritus • Infections • Malassezia • Bacterial • Dermatophytes • Immune-mediated • Pemphigus • Lupus • Plasma cell pododermatitis

Dermatophytosis: Diagnosis

• Wood's Lamp • warm up a few minutes before use • infected hairs fluoresce yellow-green • noninfected scales and crusts may appear a brighter white color - this is NOT a positive reaction • only some strains of dermatophytes glow: • M. canis, M. audouinii, M. distortum, T. schoenleinii

• Only about 50% of M. canis will fluoresce. Dermatophytosis: Diagnosis

• Fungal culture • MOST REALIABLE test • pluck hairs from the periphery of a lesion • sterile tooth brush for generalized cases

• DTM = Dermatophyte test medium • Dermatophytes utilize the protein in the media first, leading to alkaline metabolites that cause the media to turn red within 10- 14 days • Saprophytes use carbohydrates first, creating acidic metabolites – then use protein, usually after 10 - 14 days Topical Therapy • Decreases contagion—can kill ectothrix spores • Little effect on endothrix spores or hyphae within hairs • Repeat applications q 5-7 days • Lime sulfur • Miconazole/chlorhexidine • Enilconazole Dermatophytosis: Treatment

• Systemic therapy (hasten resolution) • all animals with multifocal lesions • all long haired animals • cats! • animals not responding to 2 - 4 weeks of topicals • Difficult for topicals to penetrate into hair follicles Systemic Antifungal Therapy

• Highly recommended for all dermatophyte- infected animals • Continue treatment until three negative cultures have been obtained (weekly intervals) Drug Mode of Action Dose Comments Griseofulvin Inhibits cell wall synthesis, Micronized: 25-60 mg/kg Give with fatty meal; monitor CBC for bone nucleic acid synthesis and PO q 12 h marrow suppression, do not use if FIV or FeLV + mitosis; disrupts mitotic Ultramicronized: 2.5-15 spindle formation mg/kg PO q 12 hr Ketoconazole Inhibits p450 enzymes, 5-10 mg/kg PO q 24 hr Give with food, not recommended in cats, (imidazole) blocks 14α-demethylase monitor for hepatotoxicity (rare), be aware of preventing ergosterol drug interactions synthesis + other actions Itraconazole Inhibits p450 enzymes, 5-10 mg/kg PO q 24 hr; Give with food, do not use if hepatic disease, up (triazole) blocks 14α-demethylase + may use every other week to 7.5% of dogs develop vasculitis (10 mg/kg); other actions monitor liver enzymes Fluconazole Inhibits p450 enzymes, 10 mg/kg PO q 24 hr Penetrates into CNS and eyes; monitor liver (bis-triazole) blocks 14α-demethylase enzymes Terbinafine Inhibits ergosterol 20-30 mg/kg PO q 24 hr Monitor liver enzymes (allyalamine) biosynthesis and squalene epoxidase Lufeneron Inhibits chitin synthesis 80-100 mg/kg PO q 30 d Insufficient proof of efficacy to recommend use in treatment of dermatophytosis Plasma Cell Pododermatitis

• Inflammatory disease • Associated with elevated serum globulins • ? Underlying allergies or immune-mediated disease • May be ulcerated and painful with licking of feet Feline Plasma Cell Pododermatitis

“Pillow Foot” Plasma Cell Pododermatitis

• Physical Exam • Swelling of footpads, may ulcerate • Clin Path • hypergammaglobulinemia • lymphocytosis • neutrophillia • Diagnosis • HX, PE, BX • Also test for FeLV, FIV Plasma Cell Pododermatitis

• Treatment • Doxycycline • 5 mg/kg q 12 hr; MUST drink or eat afterwards to prevent esophageal irritation and strictures • Cyclosporine • Tacrolimus topically • Glucocorticoids • Chrysotherapy (Gold salts) Immune-mediated diseases

Pemphigus foliaceous Pemphigus foliaceous

• Any age • Crusts, pustules, hair loss • Ear pinnae • Face • Clawfolds • Footpads • Nipples • Cytology • Biopsy • Treat infections • Prednisolone + CsA or chlorambucil Bowen’s Disease

• Pre-neoplastic proliferative lesions triggered by papillomavirus • Maybe pruritic (inflammatory) • Treatment options • CO2 laser • Cryosurgery • Topical imiquimod Neurogenic Pruritus --Feline

• “Twitchy cat syndrome” • Allergies? • Neurologic? • Behavioral? • “Rippling” of skin over back • Growling, hissing, biting at back or tail, running and hiding • Rule out ectoparasites, allergies, neurological disease • Treatment trials • Gabapentin • Amitriptyline • or fluoxetine • Phenobarbital Evaluation of Feline Symmetrical Alopecia Feline Symmetrical Alopecia and Dermatitis Differential Diagnoses

PRURITIC CAUSES • Parasites • Fleas • Demodex gatoi • Cheyletiella • Allergies - food, flea, environmental (atopy) • Inflammatory • Dermatophytes, Malassezia, Bacteria, Immune-mediated • Neurogenic—Feline hyperesthesia

NON-PRURITIC CAUSES • Endocrinopathies • Telogen /Anagen defluxion • Feline paraneoplastic alopecia (pancreatic, hepatic or thymic tumor) • Cutaneous T-cell lymphoma Feline Symmetric Alopecia Management

• Identify and treat cause • Skin scrapings & fecal examination (hair &/or mites) • Flea control trial • Lime sulfur or Bravecto treatment trial • Restrictive diet trial • Intradermal allergy test or serum IgE testing • Cone or bodysuit trial • Skin biopsies • Thoracic radiographs + abdominal ultrasound

Neoplastic/paraneoplastic disorders with alopecia

Feline paraneoplastic alopecia Feline Paraneoplastic Alopecia

• Associated with pancreatic adenocarcinoma and less often bile duct or hepatic carcinoma • Older cats • Sudden onset of malaise and hair loss • Marked exfoliation of hair • Shiny appearance to skin and footpads Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia Feline Paraneoplastic Alopecia

• Differential diagnosis • Feline hyperadrenocorticism • Feline skin fragility syndrome • Feline hyperthyroidism • Telogen/anagen defluxion • Feline thymoma • Metabolic epidermal necrosis • Alopecia areata • Telogen effluvium • Self-induced alopecia (feline symmetric alopecia) Feline Paraneoplastic Alopecia

• Diagnosis • Rule out other diseases (thyroid and adrenal function tests) • Skin biopsies: miniaturization of hair follicles • Abdominal ultrasonography—may find pancreatic or hepatic tumors Paraneoplastic Alopecia

• Prognosis: grave, most tumors metastasize prior to onset of clinical symptoms • Euthanasia may be humane option Exfoliative dermatitis associated with thymoma Feline Thymoma

• Reported cases have had generalized erythematous dermatitis • Skin is thickened with cracks and fissures • Hair coat is scurfy and scaly • Skin biopsies show lymphocytic interface dermatitis • Thoracic radiographs consistent with thymoma • Surgical removal usually curative • SIMILAR SIGNS AND BIOPSY FINDINGS SOMETIMES FOUND WITHOUT PRESENCE OF THYMOMA New Zealand Veterinary Journal 51(5), 244-247, 2003 Feline Cutaneous T-cell Lymphoma Ear disease in cats

• Otodectes • Apocrine gland cystadenomatosis • Nasopharyngeal polyps • Otitis secondary to allergies • Immune-mediated otitis • Proliferative necrotizing otitis • Feline solar dermatitis Polyp Removal Ear disease in cats

• Otodectes • Nasopharyngeal polyps • Apocrine gland cystadenomatosis • Otitis secondary to allergies • Immune-mediated otitis • Proliferative necrotizing otitis • Feline solar dermatitis squamous cell carcinoma Questions? Thank you to Bayer and Royal Canin for Sponsorship!

NAVDF provides up-to-date Dermatology CE (NAVDF.ORG) 2019 meeting in Austin, TX

WCVD9 in Sydney, Australia– an experience of a lifetime! (October 20-24, 2020) Karen L. Campbell, DVM, MS Diplomate, American College of Veterinary Internal Medicine Diplomate, American College of Veterinary Dermatology

University of Missouri Veterinary Health Center—Wentzville 1092 Wentzville Parkway Wentzville, MO 63385

(636) 332-5041 (636) 327-6400 fax [email protected] [email protected]