288 DISEASES/DISORDERS
Hyperpigmentation.
Urticaria (Figure 18.7).
Angioedema.
Pyotraumatic dermatitis.
Perianal pruritus.
Facial pruritus common clinical feature; cats (Figure 18.8).
Eosinophilic disease complex (eosinophilic granuloma complex); cats.
DIFFERENTIAL DIAGNOSIS
Flea bite hypersensitivity: confined to the caudal-dorsal half of the body; may be
seasonal.
Atopic disease: associated with pruritus of the face, ventrum, and feet; may be
seasonal or nonseasonal.
Scabies: pruritus specific in location (ears, elbows, and hocks); mites in skin scrapings
and/or response to specific therapy.
Drug eruption/reaction: history of drug administration before the development of
pruritus and resolution upon withdrawal.
Malasseziahypersensitivity.
Contact allergy/hypersensitivity.
Seborrheic skin disease.
Food Allergen Facts
Food allergens are typically glycoproteins with molecular weight between 10 and
70 kD.
Most patients have been fed a diet for over 2 years prior to developing a sensitivity.
Food allergens most often associated with adverse reaction: beef, dairy products,
chicken, and wheat (canine) and beef, dairy products and fish (feline); soy, corn,
eggs also reported.Grains (ex. corn) are not often a problem, contrary to popular belief.
Cross-reactivity has been reported between beef, lamb, and cow’s milk.
Potential cross-reactivity between environmental allergens and foods: ragweed and
apple/melon; cedar and tomatoes; birch and kiwi/apple/celery.
Raw diets arenotbetter for CAFR patients; processing and cooking do not disrupt (or
produce) common food allergens; raw diets are associated with exposure to higher
numbers of potentially pathogenic bacteria.DIAGNOSTICS
Food Elimination Diet
Most definitive test for cutaneous adverse food reactions.
Tailored to the individual patient; a full diet history should be obtained.