6 (1069)

g18 Diagnostic approach to pruritic dermatoses

Z. Alhaidari

The diagnostic approach to feline pruritic dermatoses must be methodical and should include certain fundamental diagnostic steps: a detailed history, thorough clinical examination, and carefully chosen diagnostic tests, selected according to the differential diagnosis. An initial rangę of tests (e.g. skin scrapings, tape strips, mycological investigations and skin smears) should be performed routinely, given the incidence of ectoparasitic infestation and dermatophytosis in the cat. Differential allergy diagnosis is based on avoidance measures (e.g. flea control and restricted diet) as allergy testing remains unreliable in this species. Skin biopsies are indicated when the history and clinical examination suggest a dermatosis that requires histological diagnosis.

g19 Diagnostic approach to alopecia

Z. Alhaidari

The diagnostic approach to alopecia must be methodical, and should involve certain fundamental steps: a detailed history, thorough clinical examination, and carefully chosen diagnostic tests, selected according to the differential diagnosis. An initial rangę of tests (e.g. skin scrapings, tape strips, and mycological investigations) should be performed routinely, given the incidence of ectoparasitic infestation and dermatophytosis in the cat. Differential allergy diagnosis is based on avoidance measures (e.g. flea control and restricted diet) as allergy testing remains unreliable in this species. Skin biopsies are indicated when the history and clinical examination suggest a dermatosis that requires histological diagnosis.

|20 Diagnostic approach to crusting dermatoses

E. Bensignor

Crusting dermatoses are a common reason for consultation in feline dermatology. Crusts can be defined as a mixture of blood, serum, exudate, and/or pus which has dried on the surface of the skin and to which scalę and hairs have become stuck. To make a specific diagnosis and institute effective treatment requires a good knowledge of the clinical aspects and causes of crusting dermatoses. The diagnostic approach rests on the history, clinical examination and appropriate diagnostic tests. It is important to distinguish 1) crusts secondary to excoriation, for which the diagnostic approach is the same as that of the pruritic dermatoses, 2) large, spontaneously-appearing crusts associated with erosions and their dried-up exudate, and 3) punctate crusts seen in miliary dermatitis, a cutaneous reaction pattern usually associated with ectoparasitic infestation or flea allergy dermatitis, and occasionally with dermatophytosis, bacterial folliculitis or atopic dermatitis.

21 Diagnostic approach to erosive and ulcerative dermatoses

E. Bensignor

In the cat, erosive and ulcerative dermatoses are a common reason for consultation, probably because of the thinness of the epidermis. Erosions and ulcers linked to self-excoriation should be distinguished from those which appear spontaneously. They are usually secondary lesions with little diagnostic significance. The diagnostic approach should involve taking the history, conducting a thorough clinical examination (generał and dermatological), and performing appropriate diagnostic tests, especially cytology and skin biopsies.