Journée thématique

COLLOQUE
DERMATOLOGIE
Conférencier
Edmund J. Rosser JR, DMV, DACVD
Une présentation de
Dimanche 17 novembre 2013
Programme de la journée
8 h 00 – 8 h 30
INSCRIPTION
8 h 30 – 10 h 00
Update on the diagnosis and treatment of food allergy
in dogs and cats
10 h 00 – 10 h 30 PAUSE
10 h 30 – 12 h 00 The differential diagnoses and management of feline pruritus
12 h 00 – 13 h 30 BRUNCH et ASSEMBLÉE GÉNÉRALE ANNUELLE
13 h 30 – 15 h 00 Cutaneous drug reactions or ‘’I wouldn’t have seen it if
I hadn’t believed it’’
15 h 00 – 15 h 15 PAUSE
15 h 15 – 16 h 45 Update on the diagnosis and treatment of sebaceous adenitis,
symmetrical lupoid onychodistrophy and seasonal flank alopecia
16 h 45 FIN DE LA JOURNÉE
EDMOND J. ROSSER JR.
DVM, DACVD
En 1976, Dr Rosser a obtenu son diplôme en médecine vétérinaire de la Cornell University. Il a
ensuite travaillé comme médecin vétérinaire pendant quatre ans avant de faire une résidence en
dermatologie à l’Université de Californie (Davis) en 1982. Médecin agrégé de l’American College
of Veterinary Dermatology, il s’est joint à la faculté du Michigan State University en 1983 où il est
professeur titulaire et directeur de la faculté de dermatologie, en plus d’être chef de la section
spécialisée. Dr Rosser a reçu le prix Norden Distinguished Teacher of the Year et, à trois
occasions, la Student Chapter of the American Veterinary Medical Association (SCAVMA) lui a
décerné le prix d’excellence en enseignement. En 2009, son exceptionnelle contribution à la
science et à l’éducation a été soulignée par l’American College of Veterinary Dermatology
(ACVD) qui lui a remis le prix d’excellence 2009. Dr Rosser est l’auteur de plus de 70 chapitres
de livres et d’articles de journaux dans le domaine de la dermatologie vétérinaire. Il a présenté
plus de 200 conférences aux vétérinaires et techniciens vétérinaires à l’échelle locale, régionale,
nationale et internationale. Dr Rosser s’intéresse plus particulièrement aux domaines des allergies
alimentaires et de la dermatite.
Pour joindre Dr Rosser :
Michigan State University, College of Veterinary Medicine, Veterinary Medical Center
Tél. : 517 353-5420
Courriel: rosser@cvm.msu.edu
DIAGNOSIS AND TREATMENT OF FOOD ALLERGY IN DOGS
Edmund J. Rosser Jr., DVM, DACVD
Prospective Clinical Evaluation of Food Allergic Dogs and Cats
Previous recommendation of a 3 week elimination diet trial was empirical
Initial recommendation in this study was to feed a home-cooked restricted diet for 60 days
In several instances the results were equivocal after 60 days and the diet was fed an additional 30 days.
Data Collected
Time elapsed before maximal clinical response on diet and
Time elapsed before return of initial clinical signs when fed previous diet
Age, breed, sex, clinical signs
Responsiveness to glucocorticoids
Concurrent disease conditions
Final treatment diets
Diets Fed
Formulated based on known past exposure; Avoided any previously consumed foods; Consisted of home
cooked foods
Protein sources - lamb, venison, moose, elk, rabbit, duck, goose, goat, ostrich, emu, alligator, kangaroo,
pinto beans
Carbohydrate source - rice, potatoes, sweet potatoes (yams), rutabagas, oats, barley
Results – Canine - Time elapsed before maximal clinical response
1-3 weeks - 13 dogs; 4-6 weeks - 25 dogs; 7-8 weeks - 10 dogs; 9-10 weeks - 3 dogs
Since the original study, dogs have now been observed to take as long as 90 days to respond to a homecooked elimination diet trial.
Results – Canine - Time elapsed before return of initial clinical signs
1-2 hours - 9 dogs; 1-3 days - 32 dogs; 7-9 days - 3 dogs; 14 days - 1 dog; 6 dogs never fed previous diet
“Why All The Fuss About Home-Cooked Elimination Diets?”
White SD: Food hypersensitivity in 30 dogs. JAVMA, vol 188 (7):695-698, 1986.
7/13 dogs (54%) with confirmed food allergy on a home-cooked lamb and rice diet, relapsed when feed a
commercial canned lamb and rice diet.
Jeffers JG, Shanley KJ, Meyer EK: Diagnostic testing of dogs for food hypersensitivity. JAVMA, vol 198
(2):245-250, 1991.
2/13 dogs with confirmed food allergy on a home-cooked lamb and rice diet, relapsed when feed a
commercial dry egg and rice diet = 15% error.
Sensitivity of serum allergen-specific IgE testing to foods (ELISA) 13 dogs = 14%.
Sensitivity of Intradermal Testing to foods in 13 dogs = 10%.
Kunkle G, Horner S: Validity of skin testing for diagnosis of food allergy in dogs. JAVMA, vol 200 (5):677680, 1992.
Out 28 dogs with a positive skin test reaction to foods, only 3 dogs responded to a home-cooked lamb
and rice diet.
Rosser EJ: Diagnosis of food allergy in dogs. JAVMA, vol 203 (2):259-262, 1993.
51 food allergic dogs confirmed over a 2-year time while being fed a home-cooked elimination diet for 10
weeks. 3 week trial only adequate for 25% of dogs.
Recent data: 25% of dogs on home-cooked elimination diets relapse when fed any form of commercial
hypoallergenic dog food.
Serologic Test for Food-Specific IgE:
Hillier A, Kunkle G: Inability to demonstrate food antigen-specific IgE antibodies in the serum of food
th
allergic dogs using the PK and oral PK tests. 10 Proceedings of the ACVD Meeting, 1994.
No + reactions in 10 know food allergic dogs.
Mueller R, Toshalis J: Evaluation of serum allergen-specific IgE for the diagnosis of food adverse
reactions in the dog. Vet Derm, 9:167-171, 1998.
No + reactions in 8 known food allergic dogs.
Ricci R, et al: A Comparison of the Clinical Manifestations of Feeding Whole and Hydrolyzed Chicken to
dogs with Hypersensitivity to the Native Protein. Vet Derm, 21:358-66, 2010.
No positive reactions in 26 known chicken sensitized dogs.
Disclaimer on allergen-specific IgE testing for foods (HESKA):
“Not all patients with adverse reactions to food have significant scores on serum IgE tests. The gold
standard for determination of food allergies remains the compliant food trial. Diet selection should include
patient diet history and should supply a restricted number of one or two novel protein sources to which
the patient has not had prior exposure. Diet trials should run a minimum of 10-12 weeks.”
Disclaimer on allergen-specific IgE testing for foods (VARL-Liquid Gold):
“Elimination diets lasting 6 to 12 weeks - the test method of choice. Feed a single protein source and a
single carbohydrate source that the patient has not eaten before. Frustrating for clients and practitioners!
Skin testing for food allergy not reliable.”
Age At Onset of Clinical Signs - Canine
Range of 4 months to 11 years – New record of age of onset of clinical signs related to a food allergy in
dogs is 13 year of age!; <1 year old - 17 dogs (33%) – including puppies at 7 weeks of age!; 1-3 years old
- 26 dogs (51%); 4-11 years old - 8 dogs (16%) - Compared to Atopic Dermatitis and Flea Allergy
Dermatitis, this is older in general for the development of an allergic skin disease.
Breeds Affected - Canine
Soft-Coated Wheaton Terrier, Dalmatian, Collie, West Highland White Terrier, Chinese Shar Pei, Lhasa
Apso, Miniature Schnauzer, Cocker and Springer Spaniels, Labrador Retriever, Golden Retriever,
German Shepherd, Bichon Frise
Clinical Signs - Canine
Non-seasonal pruritus; Most commonly affects the ears/pinnae, feet, inguinal region, axillary region,
proximal foreleg, face, neck, perianal/perineal region
Chronic, recurrent otitis externa a common problem (Serous Otitis Media observed in 81/104 children
from 1-9 years of age related to food allergy in 1 study)
Infectious Otitis Media: Defalque VE, Rosser EJ, Petersen AD: Aerobic and anaerobic bacterial microflora
th
of the middle ear cavity in normal dogs. 20 Proceedings of the ACVD Meeting, 2005.
Staphylococci, Streptococci, Enterococci, Bacilli, Bordatella bronchiseptica, NO YEAST.
May develop secondary staphylococcal pyoderma or Malassezia dermatitis
Possible history of seizures (Food Allergy and seizures in humans: seafoods and soybeans – increased
dopamine in CNS)
Concurrent diarrhea rare, may have more frequent or softer feces
Only clinical sign on presentation:
Chronic recurrent pyoderma; Seborrheic dermatitis
Response to Glucocorticoids
Complete cessation of pruritus - 39% of cases; Partial reduction in pruritus - 44% of cases; No reduction
in pruritus - 17% of cases
Concurrent Primary Pruritic Skin Diseases
Flea Allergy Dermatitis; Atopic Dermatitis; Flea Allergy and Atopic Dermatitis; Flea Collar Hypersensitivity
DIAGNOSIS
Treat suspected food allergy cases symptomatically for first 6-12 months before recommending an
elimination diet trial
Rationale For Initial Symptomatic Therapy For 6-12 Months
51 food allergic dogs followed for 3 years: Only 3 dogs re-developed pruritus; 2 dogs became flea
allergic; 1 dog became atopic; None of the dogs became pruritic due to the new hypoallergenic treatment
diet; All dogs had been eating the initial sensitizing diet for 6-12 months or longer
Dogs Started On Elimination Diet Prior To 6-12 Months Of Pruritus
2 cases initially on beef/soy based diets; Placed on lamb based diets after 3 months; Pruritus controlled
for 2 months; Pruritus re-developed and dogs found to be reacting to lamb
Dogs Started On Elimination Diet Prior To 6 Months Of Pruritus
1 case initially on lamb/rice based diet; Placed on venison based diet after 2 months; Pruritus controlled
for 3 months; Pruritus re-developed and dog found to be reacting to venison
Theory Of An Immunologic Window
Patient is genetically programmed to become sensitized to commonly exposed antigens in the diet after a
certain age; At this age, sensitization begins over a 6-12 month time period?; After this time period of
programming, the sensitizing immunologic window closes
Immunology of Food Allergy
IgE mediated food allergy: Common in children - peaks at 1 yr; Consider skin testing and in-vitro serum
testing in puppies? Rare in adults ; False negative skin tests in adults
Delayed hypersensitivity reactions to foods: More common in adults; Consider patch testing with foods
ELIMINATION DIET TRIAL – MINIMUM 12 weeks in duration
Protein hydrolysate formulated diets:
Reducing the Molecular Weight (Daltons) of a specific protein in the diet
Purina CNM Diet - HA-Formula - Hydrolyzed soy, corn starch, canola/coconut oil
Purina Gentle Snackers - Hydrolyzed soy, corn starch, canola/coconut oil, oat fiber
Hill’s Prescription Diets:
Canine z/d Ultra - Hydrolyzed chicken and chicken liver, corn starch, soybean oil
Canine z/d Low Allergen - Hydrolyzed chicken and chicken liver, potato (canine), rice (feline), soybean oil
Canine Hypoallergenic Treats - Hydrolyzed chicken and chicken liver, corn starch (dogs), rice (feline)
soybean oil
Royal Canin Veterinary Diet (Waltham)
Hypoallergenic HP19 Canine – Hydrolyzed soy, rice, chicken fat, beet pulp, vegetable oil
Home-cooked Elimination Diet Trial
Restricted diet fed for up to 90 days; Formulate based on known past exposure; Avoid any previously
consumed foods
Canine Diets
Protein sources: Lamb, venison, rabbit, duck, goose, goat, ostrich, emu, alligator, kangaroo, elk, moose
Cook by boiling, baking or broiling; Carbohydrate sources: Rice, potatoes, rutabagas – boiled, No instant
or minute forms; Sweet potatoes - baked
Add nothing to the cooking water; Mix equal portions of protein and carbohydrate (50:50) to approximate
the volume of the previous diet; 1 cup of the cooked mixture per 10 pounds of body weight per day; Will
need to increase the amount of carbohydrate 2-4 x for most dogs; Use carbohydrate and/or protein treat
between meals
“Nothing else is to pass the dog’s or cat’s lips for the next 60 days”
Discontinue all: Table scrapes; Dog treats; Chewable heartworm preventative - Flavorings in Chewable
Heartworm Preventatives: Heartgard and Heartgard Plus - Real beef, corn, soy (Unflavored tablet
available); Sentinel and Interceptor - Pork liver, soy; Iverhart Plus - Pork liver; Flavorings in Miscellaneous
Chewable Products - Proin (phenylpropanolamine) - Poultry liver; Propalin (phenylpropanolamine) – Beef;
Deramaxx (deracoxib) - Pork, soy; Baytril (enrofloxacin) - Pork liver, hydrolyzed soy; Rimadyl (carprofen) Pork liver; Chewable vitamin supplements; Essential fatty acid diet supplements
Treatment Diets - Canine
Lamb, venison or vegetable and rice based dry diets (Nature’s Recipe)
Rabbit and rice based canned diet (Nature’s Recipe)
Duck, venison, or salmon and potato based dry or canned diets; lamb and rice based canned diet, egg
and rice based dry diet (d/d, Hill’s)
Venison, duck, rabbit, or whitefish and potato based canned and dry diets (Innovative Veterinary Diets –
Royal Canin - Waltham)
Vegetable and potato/oat/rice based dry diet (IVD Select Care Vegetarian Formula)
Vegetable and rice/oatmeal/barley/potato based dry diet (Natural Balance Vegetarian Formula)
Fish and potato based dry diet (Eukanuba Response Formula FP for Dogs)
Salmon, trout and rice dry diet (Purina CNM Diet: LA-Formula); Menhaden fish meal and rice dry diet
(Royal Canin - Skin Support SS21)
Kangaroo and oat based dry diet (Eukanuba Response Formula KO for Dogs)
Fish and sweet potato based dry diets: Wellness Fish and Sweet Potato diet – whitefish, barley, rye flour,
menhaden fish meal, canola oil; California Natural Herring & Sweet Potato diet – herring, barley, oatmeal,
herring oil, sunflower oil; Natural Balance Sweet Potato and Fish diet – salmon, menhaden fish meal,
canola oil; Flint River Ranch “Fish and Chips” Trout and Sweet Potato diet – trout, millet, herring meal,
oatmeal, canola oil
Duck and sweet potato based dry diet – Fromm Duck and Sweet Potato Formula – barley, rice, oatmeal,
egg, millet, tomato pomace, canola oil, cheese, carrots, broccoli, cauliflower, apples, green beans,
cranberries, blueberries, chicory root, alfalfa sprouts, garlic, parsley
Venison based dog treats – Nature’s Recipe Healthy Skin Venison Dog Treat – soy flour, molasses, garlic
powder; Shaffer Venison Farms – Venison Dog Treats – 100% smoked venison
Sweet potato based dog treats – Sam’s Yams Sweet Potato dog Chewz – 100% dried sweet
potatoes/yams
Home Cooked Treatment Diets
Protein source: Lamb, venison, rabbit, chicken, turkey, beef, duck, ostrich
Carbohydrate source: Rice, potato, sweet potatoes, or rutabagas
Essential fatty acid dietary supplement: Derm Caps, EFA-Caps
Dicalcium phosphate; Non-flavored, additive free multiple vitamin and mineral supplement
Foods Associated With Exacerbation of Clinical Signs
Any food items being prepared in the kitchen
Meats, cheeses, cooking oils, margarine, breads, odors from various cooked foods
Peoples favorite snack foods
Popcorn, pretzels, peanuts, cookies (Oreo), potato chips, corn chips, doughnuts, pizza, French fries
“The Hoover Hound”
New Dilemma
Many patients with a possible food allergy that have already eaten and been exposed to “everything but
the kitchen sink”
Possible cross contamination of commercial diets during processing
Prescription and non-prescription hypoallergenic diets
Patients reacting to various ingredients used in the processing of commercial diets
Cross Contamination of Commercial Diets During Processing
Raditic R, Remillard RL, Tater KC: ELISA Testing for Common Food Antigens in Dry Dog Foods Used in
th
Dietary Elimination Trials. 10 Annual Proceedings of the AAVN Nutrition and Research Symposium,
2010, page 9.
3 of the 4 OTC Venison Canine Dry Foods tested positive for soy, 1 of the 4 tested positive for beef
BALANCED HOME-MADE ELIMINATION DIET FOR DOGS
5 pounds cooked potatoes, sweet potatoes, or rutabagas
1 pound cooked venison, ostrich, emu, rabbit, or duck
1 teaspoon Dicalcium phosphate (www.arcatapet.com, Item 13230)
5 tablespoons Safflower Oil (Hollywood Brand only)
1 teaspoon salt substitute (potassium chloride).
2 tablets of Nature Made® Multi Complete - Multiple Vitamin/Mineral Supplement with Iron
Feeding Guidelines:
Toy Breeds – 4-12 pounds
Small Breeds – 12-20 pounds
Medium Breeds – 20-50 pounds
Large Breeds – 50-80 pounds
1/3 – 2/3 pounds of food/day
2/3 – 1 pound of food/day
1 – 2 pounds of food/day
2 – 3 pounds of food/day
DIAGNOSIS AND TREATMENT OF FOOD ALLERGY IN CATS
Edmund J. Rosser Jr., DVM, Diplomate, ACVD
Prospective Clinical Evaluation of Food Allergic Cats
Previous recommendation of a 3 week elimination diet trial was empirical
Initial recommendation in this study was to feed a home-cooked restricted diet for 60 days
In several instances the results were equivocal after 60 days and the diet was fed an additional 30
days.
Data Collected
Time elapsed before maximal clinical response on diet
Time elapsed before return of initial clinical signs when fed previous diet
Age, breed, sex, clinical signs
Responsiveness to glucocorticoids
Concurrent disease conditions
Final treatment diets
Diets Fed
Formulated based on known past exposure
Avoided any previously consumed foods
Consisted of home cooked foods
Protein sources - rabbit, venison, lamb, duck, goose, ostrich, emu
Carbohydrate source - green peas, rarely rice or potatoes
Results - Time elapsed before maximal clinical response
1-3 weeks - 4 cats; 4-6 weeks - 7 cats; 7 weeks - 1 cat; 9 weeks - 1 cat; Recent date – diet trials x
12 weeks
Results - Time elapsed before return of initial clinical signs
15-30 minutes - 2 cats; 24 hours - 2 cats; 2-3 days - 4 cats; 6-8 days - 4 cats; 10 days - 1 cat;
Recent data – feed previous diet x 14 days
Age At Onset of Clinical Signs
Range of 3 months to 11 years; <1 year old - 3 cats (23%); 1-2 years old - 3 cats (23%); 4 years
old - 2 cats (15%); 6-11 years old - 5 cats (39%);
Compared to Atopic Dermatitis and Flea Allergy, this is older in general for the development of
an allergic skin disease; New Record = 12 years of age
Breeds Affected
Siamese, Domestic Shorthair, Domestic Longhair
Clinical Signs
Non-seasonal pruritus; Most commonly affects the ear/pinnae, pre-aural region, neck, periorbital
region and face; Miliary type lesions most common (“Miliary dermatitis”)
Eosinophilic plaques, Rodent ulcers; Feline symmetrical alopecia
Severe excoriations can occur
Angioedema, urticaria, conjunctivitis
Response to Glucocorticoids
Complete cessation of pruritus - 64% of cases; Partial reduction in pruritus - 9% of cases; No
reduction in pruritus - 27% of cases
Graham-Mize CA, Rosser EJ, Hauptman J: Absorption, bioavailability and activity of
prednisone and prednisolone in cats. Adv Vet Derm, vol. 5: 152-158.
Greater than a 6-fold difference in Cmax of oral prednisolone (Cmax= 1400 ng/ml) vs. oral
prednisone (Cmax= 220 ng/ml)
Cmax of oral prednisolone after oral prednisone only 122 ng/ml
Results indicate both a decreased gastrointestinal absorption of prednisone compared to
prednisolone, and possible decreased conversion of prednisone (inactive form) to prednisolone
(active form) by the liver in cats = 12 fold difference
Concurrent Primary Pruritic Skin Diseases
Flea Allergy Dermatitis; Atopic Dermatitis; Flea Allergy and Atopic Dermatitis; Flea Collar
Hypersensitivity
DIAGNOSIS
Treat suspected food allergy cases symptomatically for first 6-12 months before recommending
an elimination diet trial
Rationale For Initial Symptomatic Therapy For 6-12 Months
51 food allergic dogs followed for 3 years
Only 3 dogs re-developed pruritus; 2 dogs became flea allergic; 1 dog became atopic
None of the dogs became pruritic due to the new hypoallergenic treatment diet
All dogs had been eating the initial sensitizing diet for 6-12 months or longer
Dogs Started On Elimination Diet Prior To 6-12 Months Of Pruritus
2 cases initially on beef/soy based diets; Placed on lamb based diets after 3 months; Pruritus
controlled for 2 months; Pruritus re-developed and dogs found to be reacting to lamb
Dogs Started On Elimination Diet Prior To 6 Months Of Pruritus
1 case initially on lamb/rice based diet; Placed on venison based diet after 2 months; Pruritus
controlled for 3 months; Pruritus re-developed and dog found to be reacting to venison
Theory Of An Immunologic Window
Patient is genetically programmed to become sensitized to commonly exposed antigens in the
diet after a certain age
At this age, sensitization begins over a 6-12 month time period?
After this time period of programming, the sensitizing immunologic window closes
2
Immunology of Food Allergy
IgE mediated food allergy: Common in children - peaks at 1 yr.; Consider skin testing and invitro serum testing in kittens?
Rare in adults; False negative skin tests in adults
Delayed hypersensitivity reactions to foods:
More common in adults; Consider patch testing with foods
ELIMINATION DIET TRIAL – MINIMUM 8-12 weeks in duration
Protein hydrolysate formulated diets:
Reducing the Molecular Weight (Daltons) of a specific protein in the diet
Purina Veterinary Diets - HA Formula - Hydrolyzed soy (10,000 Daltons), corn starch,
canola/coconut oil – Experimental Trial Diet Only
Hill’s Prescription Diets:
Feline z/d Ultra (canned) - Hydrolyzed chicken liver (3,000 Daltons), corn starch, soybean oil
Feline z/d Low Allergen(dry) - Hydrolyzed chicken liver, rice, soybean oil
Feline Hypoallergenic Treats - Hydrolyzed chicken liver, rice, soybean oil
Royal Canin Veterinary Diet (Waltham)
Hypoallergenic HP23 Feline – Hydrolyzed soy (10,000 Daltons), rice, chicken fat, beet pulp,
anchovy oil, soya oil
Home-cooked Elimination Diet Trial
Restricted diet fed for up to 90 days; Formulate based on known past exposure; Avoid any
previously consumed foods; “Nothing else is to pass the cat’s lips for the next 60 days”
Discontinue all:
Table scrapes; Cat treats; Chewable heartworm preventative; Chewable vitamin supplements;
Essential fatty acid diet supplements
Feline Diets
Protein sources
Rabbit, lamb, venison, duck
Cook by boiling or broiling
Carbohydrate sources
Green peas
Often refuse rice or potatoes
Most often feed protein source alone
Treatment Diets - Feline
Rabbit and rice based canned diets (Nature’s Recipe)
Venison, duck, or rabbit and green pea based canned and dry diets (d/d canned, Hill’s)
Lamb and barley based canned diet (Eukanuba Response Formula LB for Cats)
Lamb, venison, duck, or rabbit and green pea based canned and dry diets (Royal
Canin/Waltham/Innovative Veterinary Diets)
3
Home Cooked Treatment Diets
Protein source
Lamb, venison, rabbit, chicken, turkey, beef, duck, goose, ostrich, emu
Carbohydrate source
Green pea, rice, potato or sweet potatoes
Essential fatty acid dietary supplement
Derm Caps, EFA-Caps
Dicalcium phosphate
Non-flavored, additive free multiple vitamin and mineral supplement
Taurine for cats
Foods Associated With Exacerbation of Clinical Signs
Any food items being prepared in the kitchen - “The Counter Cat”
Meats, cheeses, cooking oils, margarine, breads, odors from various cooked foods
Peoples favorite snack foods
Popcorn, pretzels, peanuts, cookies (Oreo), potato chips, corn chips, doughnuts, pizza, French
fries
New Dilemma
Many patients with a possible food allergy that have already eaten and been exposed to
“everything but the kitchen sink”
Possible cross contamination of commercial diets during processing
Prescription and non-prescription hypoallergenic diets
Patients reacting to various ingredients used in the processing of commercial diets
BALANCED HOME-MADE ELIMINATION DIET FOR CATS
½ pound cooked potatoes, rice, or green peas
1 pound cooked lamb, venison, ostrich, emu, rabbit, or duck
1 teaspoon Dicalcium phosphate
½ tablespoon Safflower Oil (Hollywood Brand only)
2 teaspoons light salt
2 tablets of Nature Made® Multi Complete - Multiple Vitamin/Mineral Supplement with Iron
350 mg Taurine
Feeding Guidelines:
Broil, boil, or bake lamb and grind or finely chop.
Add salt to cooking water for rice, potatoes, or green peas. Mix the safflower oil, Dicalcium
phosphate, vitamin/mineral supplement, and taurine with the rice, potatoes, or green peas, and
then add the mixture to the meat puree. Keep refrigerated and warm in microwave to increase
palatability.
Feed 2½ ounces/5 pounds of cat/day.
4
FELINE PRURITUS: DIAGNOSIS AND MANAGEMENT
Edmund J. Rosser Jr., DVM, Diplomate ACVD
Professor of Dermatology
Department of Small Animal Clinical Sciences
Michigan State University
College of Veterinary Medicine
East Lansing, MI 48824-1314
1. Differential Diagnosis of Feline Pruritus
a. Feline “Miliary Dermatitis”
b. “Feline Symmetrical Alopecia”
2. Feline Miliary Dermatitis
a. Etiology
i. A cutaneous reaction pattern, not a specific disease entity.
b. Clinical Features
i. Small focal to diffuse papular eruptions with small crusts.
ii. Usually pruritic, excoriations may occur.
c. Flea Allergy Dermatitis
i. Affects the dorsal lumbo-sacral region, caudo-medial thighs, ventral
abdomen, and flanks. May also affect the head and neck region, may
become generalized.
ii. Warm weather seasonal or non-seasonal pruritus – geographic differences.
d. Cutaneous Adverse Food Reactions - “Food Allergy”
i. Affects the pre-aural region, pinnae, neck, periorbital region, face.
ii. Severe excoriations may occur.
iii. Non-seasonal pruritus, concurrent GI signs rare!
e. Atopic Dermatitis (“Catopy”)
i. May mimic the distribution patterns of Flea Allergy or Food Allergy, or
may also present with lesions of the forelegs, rear legs, ventral abdomen
and chest.
ii. May be warm weather seasonal, present year round with exacerbations in
warm weather, or non-seasonal.
f. Parasitic Causes
i. Presence of “miliary lesions” implies a hypersensitivity response.
ii. Cheyletiellosis (“Walking Dandruff”) - affects primarily the dorsal trunk,
excess scaling a major sign.
iii. Notoedric Mange (Feline Scabies) - affects the pinnae, face, periorbital
region, neck (“Head Mange”) – heavy crusts/scales. May extend to the
feet, perineum.
iv. Trombiculosis (“Chiggers”) - affects ground contact areas – legs, feet,
ears, and ventrum with orange colored crusts.
g.
h.
i.
j.
k.
v. Otoacariasis (Ectopic Ear Mites) - may mimic the distribution patterns of
Flea Allergy, Food Allergy, or Atopy. Usually has concurrent otitis
externa.
vi. Demodicosis - Demodex cati – long slender mite. Affects the periorbital
region, head, and neck with concurrent ceruminous otitis externa.
vii. Pediculosis (Lice) - Felicola subrostrata. Affects primarily the dorsal
trunk. Presence of “nits” on hair shafts.
viii. Cat Fur Mite - Lynxacarus radovsky. Affects primarily the dorsal trunk.
“Salt and pepper” like scale.
ix. Intestinal Parasite Hypersensitivity - roundworms, hookworms,
whipworms, tapeworms, Coccidia. May mimic the distribution patterns of
Flea Allergy, Food Allergy, or Atopy.
Fungal Causes
i. Dermatophytosis - may mimic the distribution patterns of Flea Allergy,
Food Allergy, or Atopy. Additional areas of patchy alopecia, scales.
History of other pets or humans in the household with skin lesions.
ii. Malassezia Dermatitis - secondary complication.
Autoimmune Causes
i. Pemphigus Foliaceus - affects the nasal planum, periorbital region, and
pinnae. May become generalized. May be systemically ill.
ii. Pemphigus Erythematosus - lesions limited to the nasal planum,
periorbital region, pinnae.
Immune Mediated Causes
i. Cutaneous Drug Reaction - often mimics the distribution pattern of Food
Allergy. Methimazole reported, Propranalol.
ii. Hypereosinophilic Syndrome - multisystemic organ involvement.
Anorexia, vomiting, diarrhea, weight loss. Generalized miliary lesions and
pruritus.
Neoplastic Causes
i. Cutaneous Mastocytosis - most commonly affects the head and neck
region, may be generalized. Geriatric Siamese cats predisposed.
Gastrointestinal ulcers, coagulation disorder.
ii. Epitheliotropic Cutaneous Lymphoma (Mycosis Fungoides) - the “Great
Imitator”.
Viral Causes
i. Feline Herpes Virus - affects the nasal region and face. May have a history
of previous upper respiratory infections. May have history of
conjunctivitis and/or oral ulcers.
ii. FeLV and FIV Associated Skin Lesions - chronic “miliary dermatitis”
with concurrent systemic illness.
l. Idiopathic Causes
i. Idiopathic Sterile Granuloma and Pyogranuloma - may mimic the
distribution pattern of Food Allergy. Spontaneous remission may occur.
ii. Idiopathic “Miliary Dermatitis” - relatively rare. A diagnosis of exclusion!
3. Feline Symmetrical Alopecia
a. Etiology
i. A symptom of several possible underlying diseases.
ii. Not a specific disease entity. A result of excess symmetrical licking with
the “barbs” of the tongue fracturing the hair shafts.
iii. Rarely is the alopecia spontaneous.
b. Clinical Features
i. A non-inflammatory, symmetrical alopecia.
ii. Most commonly affects the ventral abdomen, inguinal region, perineum,
dorsal lumbosacral region, medial and posterior thighs.
iii. May also affect the entire ventrum, anterior and medial forelegs.
iv. May affect “anywhere the cat can lick”.
v. Close inspection reveals diffuse thinning of hair rather than “total”
alopecia. Owner often unaware of excess grooming behavior.
vi. May be “secretive” or nocturnal groomers.
vii. Problem with “hair balls”.
c. Flea Allergy Dermatitis
i. Most commonly affects the dorsal lumbo-sacral region, caudo-medial
thighs, ventral abdomen, and flanks.
ii. Warm weather seasonal or non-seasonal pruritus – geographic differences.
d. Cutaneous Adverse Food Reactions - “Food Allergy”
i. Often affects the ventral abdominal, inguinal regions.
ii. May also have “miliary lesions” in the pre-aural region, pinnae, neck,
periorbital region, and face.
iii. Non-seasonal pruritus, concurrent GI signs rare!
e. Atopic Dermatitis (“Catopy”)
i. Most commonly affects the medial thighs, entire ventrum, forelegs.
ii. May mimic the distribution patterns of Flea Allergy or Food Allergy.
iii. May be warm weather seasonal, present year round with exacerbations in
warm weather, or non-seasonal.
f. Parasitic Causes
i. Cheyletiellosis (“Walking Dandruff”) - affects primarily the dorsal trunk
with excess scaling a major sign. Symmetrical alopecia of the ventral
abdomen.
ii. Demodicosis - Demodex gatoi – short stubby mite. Symmetrical alopecia
of the ventral abdomen.
iii. Otoacariasis (Ectopic Ear Mites) - may mimic the distribution patterns of
Flea Allergy, Food Allergy, or Atopy. Usually has concurrent otitis
externa.
g.
h.
i.
j.
k.
iv. Pediculosis (Lice) - Felicola subrostrata. Affects primarily the dorsal
trunk. Presence of “nits” on hair shafts.
v. Cat Fur Mite - Lynxacarus radovsky. Affects primarily the dorsal trunk.
“Salt and pepper” like scale.
vi. Intestinal Parasite Hypersensitivity - roundworms, hookworms,
whipworms, tapeworms, Coccidia. May mimic the distribution patterns of
Flea Allergy, Food Allergy, or Atopy.
Fungal Causes
i. Dermatophytosis - most commonly has areas of “patchy” alopecia, scales.
History of other pets or humans in the household with skin lesions.
ii. Malassezia Dermatitis - secondary complication. Brownish discoloration
to the skin.
Miscellaneous Causes
i. Hyperthyroidism - excess grooming from “hyperexcitable” behavior.
ii. Lower Urinary Tract Infections - affects the ventral abdomen.
iii. Impacted anal glands (Anal sacculitis) - affects the perineal, perianal
region.
Endocrine Causes
i. Hyperadrenocorticism - spontaneous symmetrical, truncal alopecia, easily
epilated hairs. May have concurrent “skin fragility”.
ii. Hypothyroidism - ????
Neoplastic Causes
i. Pancreatic Paraneoplastic Alopecia - geriatric cats. Alopecia most
commonly on the ventrum and legs. Skin takes on a “shiny” appearance.
Easily epilated hairs. Concurrent anorexia, lethargy.
Psychogenic Causes
i. Feline Psychogenic Alopecia - an anxiety neurosis. Often due to a
disturbing influence. New puppy or kitten, barking dogs, new baby, recent
move, etc. Emotional breeds: Burmese, Siamese, Abyssinian. Sequela to
previous pruritic skin disease. Most commonly affects the easiest areas to
reach; medial thighs, ventral abdomen, medial forelegs. Darkened hair
color in Siamese cats due to melanin pigment increase with cooler skin
temperature.
4. Feline Pruritus – Diagnosis
a. Feline Miliary Dermatitis: Flea Allergy Dermatitis
i. Distribution pattern of lesions - posterior 1/3 of the body.
ii. Seasonal pruritus.
iii. Intradermal testing with flea antigen, in-vitro testing for flea.
iv. Response to intense flea treatment protocol.
b. Feline Miliary Dermatitis: Cutaneous Adverse Food Reactions -“Food Allergy”
i. Distribution pattern of lesions - anterior 1/3 of the body.
c.
d.
e.
f.
g.
h.
i.
ii. Non-seasonal pruritus.
iii. Home cooked, novel protein and carbohydrate elimination diet 8-12 weeks
in duration.
iv. Protein Hydrolysate Diets
1. Reduced molecular weight (Daltons) of specific protein in diet.
2. Most “allergenic” proteins are in range of 14,000 – 70,000
Daltons.
3. Hydrolyzed proteins in the range of 1,000 – 12,000 Daltons.
v. Feline Commercial Protein Hydrolysate Diets
1. Royal Canin Veterinary Diet: Feline Hypoallergenic HP23 hydrolyzed soy, chicken fat, rice, beet pulp, fish oil.
2. Hill’s Prescription Diets: Feline z/d Low Allergen – hydrolyzed
chicken and chicken liver, rice, vegetable oil.
Feline Miliary Dermatitis: Atopic Dermatitis (“Catopy”)
i. Mimics Flea Allergy and Food Allergy.
ii. Seasonal or non-seasonal pruritus.
iii. Intradermal testing with aeroallergens.
iv. Aeroallergen specific IgE immunoassay.
Feline Miliary Dermatitis: Parasitic Causes
i. Distribution pattern of lesions
ii. Skin scrapings, Scotch tape preparations, flea combing, fecal flotation,
vacuum technique.
iii. Response to empirical parasiticidal treatments - lime sulfur dips vs.
selamectin vs. ivermectin vs. fipronil spray.
Feline Miliary Dermatitis: Dermatophytosis
i. Areas of patchy alopecia, scales.
ii. History of other pets or humans in the household with skin lesions.
iii. Wood’s lamp examination, KOH prep, fungal cultures, skin biopsy.
Feline Miliary Dermatitis: Pemphigus Foliaceus
i. Affects the nasal planum, periorbital region, and pinnae.
ii. May become generalized, and systemically ill.
iii. Histopathology - subcorneal pustules with acantholytic cells.
Feline Miliary Dermatitis: Pemphigus Erythematosus
i. Lesions limited to the nasal planum, periorbital region, pinnae.
ii. Histopathology - subcorneal pustules with acantholytic cells.
Feline Miliary Dermatitis: Cutaneous Drug Reaction
i. Distribution pattern of lesions - mimics Food Allergy.
ii. History of drug use and response to drug withdrawal.
iii. Histopathology – varied.
Feline Miliary Dermatitis: Hypereosinophilic Syndrome
i. Many organs involved, anorexia, vomiting, diarrhea, weight loss.
ii. Moderate to marked eosinophilia.
iii. Histopathology – superficial and deep perivascular to interstitial dermatitis
with eosinophils.
j. Feline Miliary Dermatitis: Neoplastic Causes
i. Cutaneous Mastocytosis - geriatric Siamese cats predisposed.
Gastrointestinal ulcers, coagulation disorder.
ii. Epitheliotropic Cutaneous Lymphoma (Mycosis Fungoides) - the “Great
Imitator”.
k. Feline Miliary Dermatitis: Feline Herpes Virus
i. Distribution pattern of lesions - affects the nasal region and face.
ii. History of previous upper respiratory infections, conjunctivitis, oral ulcers.
iii. Histopathology - epithelial cell intranuclear inclusion bodies.
iv. PCR for Feline Herpes virus 1.
l. Feline Miliary Dermatitis: Idiopathic Sterile Granuloma and Pyogranuloma
i. Distribution pattern of Food Allergy.
ii. Histopathology - Perifollicular pyogranulomatous dermatitis or;
Preauricular xanthogranuloma – a diffuse granulomatous dermatitis with
multinucleated giant cells.
iii. Chronic steroid or megestrol acetate use.
m. Feline Miliary Dermatitis: Idiopathic “Miliary Dermatitis”
i. Histopathology - superficial perivascular dermatitis with neutrophils,
eosinophils, plasma cells, mast cells.
5. Feline Symmetrical Alopecia - Diagnosis
a. Spontaneous vs. Post-traumatic alopecia
i. Physical exam - rarely is area completely alopecic, hairs do not easily
epilate.
ii. Trichogram - anagen bulbs with broken distal ends vs. telogen bulbs with
fine pointed ends.
b. Feline Symmetrical Alopecia: Flea Allergy Dermatitis
i. Distribution pattern of lesions - posterior 1/3 of the body.
ii. Seasonal pruritus.
iii. Intradermal testing with flea antigen or in-vitro testing for flea.
iv. Response to intense flea treatment protocol.
c. Feline Symmetrical Alopecia: Cutaneous Adverse Food Reactions -“Food
Allergy”
i. Often affects the ventral abdominal, inguinal regions.
ii. Non-seasonal pruritus.
iii. Home cooked, novel protein and carbohydrate elimination diet 8-12 weeks
in duration.
iv. Protein Hydrolysate Diets
4. Reduced molecular weight (Daltons) of specific protein in diet.
5. Most “allergenic” proteins are in range of 14,000 – 70,000
Daltons.
6. Hydrolyzed proteins in the range of 1,000 – 12,000 Daltons.
ii. Feline Commercial Protein Hydrolysate Diets
d.
e.
f.
g.
h.
i.
j.
k.
l.
1. Royal Canin Veterinary Diet: Feline Hypoallergenic HP23 hydrolyzed soy, chicken fat, rice, beet pulp, fish oil.
2. Hill’s Prescription Diets: Feline z/d Low Allergen – hydrolyzed
chicken and chicken liver, rice, vegetable oil.
Feline Symmetrical Alopecia: Atopic Dermatitis (“Catopy”)
i. Most commonly affects the medial thighs, entire ventrum, and forelegs.
ii. Seasonal or non-seasonal pruritus.
iii. Intradermal testing with aeroallergens.
iv. Aeroallergen specific IgE immunoassay.
Feline Symmetrical Alopecia: Parasitic Causes
i. Most frequently Cheyletiellosis and Demodicosis.
ii. Skin scrapings, Scotch tape preparations, flea combing, fecal flotation,
vacuum technique.
iii. Response to empirical parasiticidal treatments. Lime sulfur dips vs.
selamectin vs. ivermectin vs. fipronil spray.
Feline Symmetrical Alopecia: Dermatophytosis
i. Most commonly have areas of “patchy” alopecia, scales.
ii. History of other pets or humans in the household with skin lesions.
iii. Wood’s lamp examination, KOH prep, fungal cultures, skin biopsy.
Feline Symmetrical Alopecia: Hyperthyroidism
i. Basal total serum thyroxine (T4).
Feline Symmetrical Alopecia: Lower Urinary Tract Infections
i. Urine culture and susceptibility.
Feline Symmetrical Alopecia: Impacted anal glands (Anal sacculitis)
i. Anal gland extirpation.
Feline Symmetrical Alopecia: Hyperadrenocorticism
i. Spontaneous symmetrical, truncal alopecia, easily epilated hairs.
ii. May have concurrent “skin fragility”.
iii. Dexamethasone suppression test - 0.1 mg/kg – baseline, 4 & 8 hours post
dexamethasone.
iv. ACTH stimulation test - measure both cortisol and progesterone.
Feline Symmetrical Alopecia: Pancreatic Paraneoplastic Alopecia
i. Geriatric cats with alopecia most commonly on the ventrum, legs.
ii. Skin takes on a “shiny” appearance.
iii. Histopathology - marked follicular atrophy with a mild mononuclear
perivascular dermatitis.
iv. Abdominal ultrasound.
v. Serum trypsin-like immonoreativity (TLI).
Feline Symmetrical Alopecia: Feline Psychogenic Alopecia
i. History of change in cat’s environment.
ii. Non-responsive to Prednisolone.
iii. Elizabethan collar response test.
iv. Histopathology - normal or very mild superficial perivascular dermatitis.
6. Feline Pruritus – Treatment
a. Flea Allergy Dermatitis
i. Environmental treatment - pyrethroid + pyriproxifin; boric acid or sodium
polyborate powder.
ii. Patient treatment - Imidacloprid – q14d + leufenuron – q30d; Fipronil +
methoprene – q21d.
iii. Aqueous hyposensitization with flea salivary antigen.
b. Cutaneous Adverse Food Reactions – “Food Allergy”
i. Commercial diet avoiding the known offending food source.
ii. Nature’s Recipe – rabbit and rice canned diet.
iii. Hill’s Prescriptions Diets: Feline d/d – venison and green pea based dry or
canned diet; duck or rabbit and green pea based dry diet.
iv. Eukanuba Response Formula LB for Cats – lamb and barley based canned
diet.
v. IVD – Royal Canin – Waltham: duck, rabbit, venison, or lamb and green
pea – canned or dry diets.
vi. Home-cooked Treatment Diets - “novel” protein and carbohydrate source,
essential fatty acid dietary supplement, safflower oil, dicalcium phosphate,
non-flavored, additive free vitamin and mineral supplement, and taurine
for cats.
c. Atopic Dermatitis (Catopy)
i. Allergen specific immunotherapy (ASIT).
ii. Prednisolone (not Prednisone) - 1 mg/kg q12h x 7 d, then q24h x 7 d, then
q48h at lowest possible dose to control pruritus.
iii. Cyclosporine – 5 mg/kg q24h.
d. Parasitic Diseases
i. Lime sulfur – q7d x 4 weeks - Cheyletiella, Notoedres, Trombicula,
Lynxacarus, Demodex gatoi, Felicola subrostrata.
ii. Selamectin – q14d x 3 treatments - Cheyletiella, Notoedres, Otodectes.
iii. Fipronil spray – q30d - Cheyletiella, Notoedres, Felicola subrostrata.
iv. Ivermectin - 200 ug/kg q7d x 4 weeks - Cheyletiella, Notoedres,
Otodectes; 200-300 ug/kg q24h - Demodex cati.
v. Amitraz – 125 ppm q14d - Cheyletiella, Notoedres, Trombicula,
Lynxacarus, Demodex gatoi, Demodex cati, Felicola subrostrata.
e. Dermatophytosis: Systemics
i. Itraconazole - 5-10 mg/kg q24h with food for 4-6 weeks.
ii. Terbinafine - 30 mg/kg q24h for 4-6 weeks.
iii. Lufenuron - 60-100 mg/kg q30d x 2 treatments.
f. Dermatophytosis: Topicals
i. Lime sulfur - twice weekly for 4-6 weeks.
ii. Enilconazole topical solution (10%) - twice weekly for 4-6 weeks.
iii. Miconazole shampoo and leave on rinse 2% (ResiZole) - twice weekly for
4-6 weeks.
g. Pemphigus foliaceus and Pemphigus erythematosus
i. Prednisolone (not Prednisone) - Induction dosage - 2 mg/kg q12h;
Maintenance dosage - gradually decrease the dosage every 2 weeks to
prevent a relapse.
ii. Chlorambucil - Induction dosage – 0.1 mg/kg q48h; Maintenance dosage –
0.05 mg/kg q48h.
h. Drug Eruption
i. Discontinue suspected drug.
ii. Avoid chemically related or similar drugs.
iii. Best advice: “Do no harm!”
i. Hypereosinophilic Syndrome
i. Prednisolone (not Prednisone) - Induction dosage - 2 mg/kg q12h;
Maintenance dosage - gradually decrease the dosage every 2 weeks to
prevent a relapse.
ii. Alpha interferon - 30-60 IU orally q24h.
iii. Poor prognosis.
j. Cutaneous Mastocytosis
i. Spontaneous remission may occur.
ii. Prednisolone (not Prednisone) - Induction dosage - 2 mg/kg q12h;
Maintenance dosage - gradually decrease the dosage every 2 weeks.
iii. Chlorambucil - Induction dosage – 0.1 mg/kg q48h; Maintenance dosage –
0.05 mg/kg q48h.
k. Epitheliotropic Cutaneous Lymphoma (Mycosis Fungoides)
i. Prednisolone and Chlorambucil – as above.
ii. Lomustine - 60 mg/m2 q21d.
l. Feline Herpes Virus
i. Pure lysine granules (78.8% lysine) - ¼ teaspoon (~570 mg) q12h for life.
ii. L-lysine tablets (without propylene glycol) - 250-500 mg/cat for life.
iii. Imiquimod 5% cream - 3 times weekly.
iv. Alpha interferon - 30-1000 IU orally q24h.
m. Hyperadrenocorticism
i. Unilateral/Bilateral adrenalectomy - Mineralocorticoid maintenance:
Fludrocortisone acetate – 0.1-0.3 mg/cat or Desoxycorticosterone pivalate
– 2.2 mg/kg SQ once monthly. Glucocorticoid maintenance: Prednisolone
– 1.25-2.5 mg/cat/day
ii. Metyrapone – 65 mg/kg q12h.
n. Pancreatic Paraneoplastic Alopecia
i. Screen for evidence of metastasis.
ii. Radiographs and ultrasound - liver, diaphragm, lungs.
iii. Partial pancreatectomy.
o. Feline Psychogenic Alopecia
i. Correct or remove disturbing influence.
ii. Mood altering drugs
1.
2.
3.
4.
5.
Clomipramine – 1.25-2.5 mg/cat/d.
Amitriptyline – 5 mg/cat q12h.
Hydroxyzine – 10 mg/cat q12h.
Paroxetine HCl – 2.5 mg/cat q24h.
Phenobarbital – 1/8 grain BID; increase by 1/8 grain every 2-3
weeks until cat is sedated or stops licking.
6. Progestational compounds (last resort) – Megestrol acetate
(Ovaban®) – 2.5 – 5.0 mg/cat q48h until hair regrows, then q 7
days as maintenance.
DIAGNOSIS AND M ANAGEMENT OF CUTANEOUS DRUG REACTIONS IN DOGS AND
CATS
Edmund J. Rosser Jr., DVM, Diplomate ACVD
PATHOGENESIS:
Immunologic
Type I, II, III, IV hypersensitivity reactions
Nonimmunologic
Related to pharmacology of the drug; Predictable, dose dependent
Route of administration
Oral; Topical; Injectable; Inhalation
Clinical Presentations:
Erythema multiforme
Toxic epidermal necrolysis
Pemphigus foliaceus
Vaccine reaction
Cutaneous vasculitis
Lichenoid Drug Eruption
Unique Feline Reactions:
Miliary dermatitis reaction
Vaccine reaction
Injection site fibrosarcomas
ERYTHEM A MULTIFORME
Drug-induced apoptosis - Programmed cell death
Acute onset of lesions; Erythematous macules; “Target lesions”; Urticarial plaques; Vesicles and
bullae; Concurrent systemic illness; Fever, depression, anorexia
Mucous membrane involvement; Vesicles, bullae, ulcers
Erythema multiforme major or Stevens-Johnson syndrome - Can be life threatening
Drugs implicated
Aurothioglucose; Cephalexin, chloramphenicol, gentamicin, trimethoprim sulfas, ormetoprim
sulfas, tetracycline; Diethylcarbamazine, levamisole; L- thyroxine, phenobarbitol
TOXIC EPIDERM AL NECROLYSIS
Severe erythema multiforme? Massive and sudden apoptosis
Diffuse erythematous rash; Vesicles and bullae; Full thickness skin sloughing and ulcers
May affect footpads, mucous membranes
Lesions usually painful
Concurrent fever, anorexia, lethargy, depression
Secondary sepsis a problem; Often a fatal disease
Drugs implicated
Penicillins, cephalosporins, trimethoprim sulfas; Griseofulvin; Levamisole; 5- fluorocytosine;
Topical flea dips (D-limonene)
DRUG-INDUCED PEMPHIGUS
Mimics Pemphigus foliaceus
Acute, transient pustular eruptions; Subsequent crusts, scales, erosions, epidermal collarettes;
Variable distribution patterns; Systemic illness rare
Drugs implicated
Ampicillin, cephalosporins, sulfonamides; Diethylcarbamazine, thiabendazole; Cimetidine,
procainamide
VACCINE REACTIONS
Most commonly observed at site of a subQ or IM vaccination: Rabies, DHLP- Parvo
Can occur from weeks to months post-vaccination - Focal area of alopecia and
hyperpigmentation
Breed predisposition
Poodle, Bichon Frise; Shih Tzu, Lhasa Apso; Miniature Schnauzer, Yorkshire Terrier, Bedlington
Terrier, Silk y Terrier
Most spontaneously resolve over several months; Lesion may remain static
Area of alopecia and hyperpigmentation can gradually enlarge over months to years
Treatment
Tincture of time; Surgical excision; Pentoxifylline (Trental) - 15-30 mg/kg TID x 3 months
CUTANEOUS VASCULITIS
Palpable purpura, hemorrhagic bullae; Craterform ulcers, full thickness skin sloughing
Acrocyanosis of distal extremities; Large areas of erythematous or purplish skin; Does not blanch
on dioscopy; Lesion often painful; Pitting edema of distal extremities; Concurrent systemic illness
- Anorexia, depression, fever
Drugs implicated
Penicillins, sulfonamides, cephalosporins, dexamethasone; DHLP- Parvo vaccine
LICHENOID DRUG ERUPTION
Solitary to multiple papillomatous or plaque-like lesions
Drugs implicated:
Cyclosporine (Atopica, Neoral, Gengraf)
MILIARY DERM ATITIS REACTION
Miliary lesions - Affects head, face, neck regions; Intense pruritus
Mimics “food allergy”
Drugs implicated: Methimazole (Tapazol), Propranolol
VACCINE REACTION
Injection site fibrosarcomas
Interscapular and femoral regions - Associated with either subQ or IM injections
Tumor may develop 1-2 years post –vaccination; Vaccines implicated: FeLV, Rabies, FVRCP
DIAGNOSIS OF CUTANEOUS DRUG REACTIONS
History
Observed reaction does not resemble pharmacologic action
Prior exposure to drug may have been well tolerated
Reaction can be reproduced by small amounts of drug
Reaction consistent with a known hypersensitivity response
Reaction occurs within several days of drug exposure
Resolution within several days of drug withdrawal
2
Drug rechallenge
Proves cause and effect relationship; Clinical signs often more severe; Outcome can be fatal
Erythema Multiforme:
Histopathology - Hydropic interface dermatitis; Dyskeratotic keratinocytes with satellitosis;
Superficial perivascular infiltrates with mononuclear cells
Toxic Epidermal Necrolysis:
Histopathology - Hydropic degeneration of basal cells; Coagulation necrosis of epidermis;
Absence of dermal inflammation; Dermoepidermal separation and bullae formation
CLINICAL CRITERIA
EMm
EMM
SJS
OVE
TEN
Flat or raised, focal
or multifocal, target lesions
Yes
Yes
No
No
No
Number of mucosa involved
<1
>1
>1
>1
>1
Erythematous or purpuric,
macular or patchy eruption
<50%
<50%
>50%
>50%
>50%
10-30
>30%
Epidermal detachment
<10%
<10%
<10%
Olivry T et al: Erythema multiforme, Stevens-Johnson syndrome, and toxic epidermal necrolysis
in the dog: Clinical classification, drug exposure, and histopathological correlations. Proceedings
of the Autumn Meeting of the British Veterinary Dermatology Study Group, 1998, York, United
Kingdom.
Pemphigus Foliaceus:
Histopathology - Subcorneal pustules; Acantholytic cells; Neutrophils, eosinophils; Involvement
of hair follicles
Vaccine Reaction:
Histopathology - Vasculitis, panniculitis; Dermal edema; Atrophic hair follicles; Hydropic
degeneration of basal cells
Cutaneous Vasculitis:
Histopathology - Most commonly leukocytoclastic; Neutrophils in vessel walls - “Nuclear dust”;
Fibrinoid degeneration, thrombi; Perivascular hemorrhage and edema
LICHENOID DRUG ERUPTION:
Histopathology - Psoriasiform lichenoid dermatosis – with or without papillomavirus
UNIQUE FELINE REACTIONS:
Miliary dermatitis:
Histopathology - Epidermal crusts, spongiosis; Neutrophilic, eosinophilic vesicopustules;
Eosinophilic perivascular infiltrates
Vaccine Reactions:
Histopathology - Fibrosarcoma
TREATMENT
Discontinue suspected drug; Avoid chemically related or similar drugs
W hen multiple drugs are present: all should be discontinued
3
Best advice: “Do no harm!”
For Idiopathic cases (Erythema multiforme, cutaneous vasculitis, miliary dermatitis) – consider
hydrolysate treated or home-cooked elimination diet trial
Supportive Therapy - IV Fluids
Systemic antibiotics in septic patients
Broad spectrum initially: Cephalexin - 22 mg/kg TID
Gram negative organisms - Ciprofloxacin - 22 mg/kg SID
Immunosuppressive Drugs
Extremely controversial - May actually be contraindicated; Increased risk of infections, delayed
healing; Indicated in drug induced Erythema Multiforme major
Corticosteroids: Prednisolone - 2 mg/kg SID-BID
Immune Modulating Drugs: Cyclophosphamide - 2 mg/kg SID; Cyclosporine (Neoral, Gengraf,
Atopica) - 5 mg/kg SID-BID; Azathioprine (Imuran) - 2 mg/kg SID, Pentoxifylline (Trental) – 15-30
mg/kg TID
4
SEBACEOUS ADENITIS
Edmund J. Rosser Jr., DVM, Diplomate ACVD
Professor and Head of Dermatology
Department of Small Animal Clinical Sciences
Michigan State University, College of Veterinary Medicine
ETIOLOGY
Unknown; May be an immune mediated disease.
A genetically inherited defect – autosomal recessive trait.
Keratinization abnormality with obstruction of sebaceous duct?
Abnormality in sebaceous lipids – necessary for dissolution of external root sheath
CLINICAL FEATURES - 2 forms
Sebaceous Adenitis with Hyperkeratosis – Long Coated Breeds
Seen in all color variants of standard poodles (may be similar in other long-coated breeds of dogs
such as Samoyeds, Akitas, and Havanese).
A symmetrical partial alopecia and excess scaling with follicular casts. Remaining hair is dull and
brittle.
Affects dorsal planum of the nose, top of head, dorsal neck and trunk, tail and pinnae.
Non-pruritic and no offensive odor
May develop secondary bacterial folliculitis with pruritus.
Hair may become straight and lose its “curl”.
Granulomatous Sebaceous Adenitis – Short Coated Breeds
Affects short-coated breeds of dogs - Vizslas, Weimaraners, Dachshunds
Begins as a moth-eaten alopecia with minimal to no scaling.
Primarily affects the trunk, head and ears; Non-pruritic
DIAGNOSIS
Histopathology
Initial nodular granulomatous to pyogranulomatous inflammation at the level of the sebaceous
glands; Depending on the type, there may or may not be prominent hyperkeratosis; Chronic cases
develop a complete loss of sebaceous glands with fibrosis, atrophy of hair follicles and in some
cases complete loss of the adnexa with fibrosis.
Treatment
Propylene glycol - a hygroscopic lipid solvent that penetrates the horny layer and increases water
content. 50-75% propylene glycol with water-applied daily as a spray.
Bath Oil Treatments (light mineral oil) – 50:50 mixture of bath oil and water, spray over the entire
body, rub into the hair coat well, allow to soak for 1-2 hours. Remove oil by bathing with dish soap
2-3 times, and then finish with a moisturizing shampoo and conditioner/crème rinse for the final
bathing. Repeat q 7 days for the first month, the q 14-30 days prn.
EFA Supplement - Derm Caps ES - 1 capsule BID; Evening Primrose Oil (EPO) - 500 mg BID.
Anti-seborrheic shampoos, conditioners and emollients have been of little benefit.
Treat secondary pyoderma if present.
Isotretinoin (Accutane®) - 1 mg/kg SID-BID: Side effects – KCS, pruritus, erythema, lethargy,
vomiting, abdominal distention, collapse, swollen tongue, hyperactivity
Acetretin (Soriatane®) - 1 mg/kg SID-BID: Side effects – KCS, dry mucous membranes,
generalized joint stiffness, alopecia, pruritus, cracked foot pads, myalgia (muscles of mastication),
vomiting.
Retinoid toxicities - Toxicities – increased liver enzymes (ALT, AST), increase in
cholesterol and triglycerides, blood dyscrasias (increased platelets, decreased RBC,
WBC)
Teratogenic – marked decrease in availability for dogs: requires registration and forms.
Recent strict regulations – registered physicians only!
Cyclosporine (Neoral, Gengraf, Atopica) - 5 mg/kg BID - Major side effect – vomiting; Cerenia – 2
mg/kg given 1 hour prior to dosing.
Other side effects – diarrhea/anorexia/weight loss; gingival hyperplasia; verrucous skin
lesions; hirsutism; lameness; hyperglycemia; opportunistic infections; neoplasia
(lymphoma?).
Retinol (Vitamin A) – 8,000-20,000 IU – SID-BID
Surface Lipids: Dermoscent Essential 6 – PUFA’s, rosemary oil, vitamin E – apply weekly;
Allerderm® Spot-On (Virbac) – ceramides, fatty acids – apply 1-3 times weekly
Tetracycline and Niacinamide – 22 mg/kg of each drug TID, not to exceed 500 mg TID for each
drug - Tetracycline toxicity – hepatotoxic; Niacinamide side effects – anorexia, lethargy
Doxycycline – 5-10 mg/kg SID, with or without Niacinamide - Hepatotoxic at higher doses
PROGNOSIS
Akitas – tends to be more severe, chronic recurrent pyoderma more f a problem, possible signs of
systemic illness.
Standard Poodles – aesthetic disease, secondary pyoderma rare, difficult to regrow “normal” hair
coat, however recent use of lipid treatments are encouraging.
Short Coated Breeds – occasionally “cured” by treatment.
SEASONAL FLANK ALOPECIA
Edmund J. Rosser Jr., DVM, Diplomate ACVD
Professor and Head of Dermatology
Department of Small Animal Clinical Sciences
Michigan State University, College of Veterinary Medicine
ETIOLOGY
Unknown - Change in photoperiod important.
Role of pineal gland controlled hormones – Prolactin and Melatonin – normally increases with a
decrease in photo-period.
Localized hair follicle hormone receptor abnormality.
SEX PREDISPOSITION
Most frequently reported in spayed females.
Can occur in intact males or females and neutered males.
BREED PREDISPOSITION
Boxers, Airedale Terriers, Bulldogs, Giant and Miniature Schnauzers, Bouvier de Flanders,
Doberman Pinschers, Scottish Terriers, German Wirehaired Pointers
CLINICAL FEATURES
Bilaterally symmetrical alopecia with hyperpigmentation; Affects primarily the flank region; May
extend to the lateral thorax or dorsally
Most commonly occurs in fall/early winter and resolves in late spring/early summer; Cyclical
pattern may vary.
DIAGNOSIS
History and physical exam
Rule out other endocrine skin diseases – Hypothyroidism, Cushing’s Disease, Reproductive
hormone imbalances, So –called “Alopecia-X”
Histopathology - Follicular atrophy, keratin plugging, comedone formation; “Witches-foot”
appearance; Hypermelanosis.
TREATMENT
Manipulation of photoperiod
Use of exogenous prolactin or melatonin - Melatonin – 1-6 mg/dog TID for the duration of the
Alopecic cycle. Needs to be started prior to the onset of alopecia.