Feline atopic dermatitis: a retrospective study of 45 cases (2001–2012)

BACKGROUND: Atopic dermatitis (AD) is recognized as a common cause of pruritus in cats, but it remains incompletely characterized. HYPOTHESIS/OBJECTIVES: The aim of the study was to evaluate cases of confirmed feline AD. ANIMALS: Fourty‐five cats from a dermatology referral practice (2001–2012). METHODS: A retrospective case record review was carried out using strict diagnostic criteria, including exclusion of flea‐bite hypersensitivity and adverse food reaction. RESULTS: Disease prevalence was 12.5%, with domestic mixed (n = 24), Abyssinian (n = 6) and Devon rex (n = 3) cat breeds predisposed. Median age of onset was 2 years (62% <3 years; 22% >7 years; range 3 months to 12 years). Common presentations were severe (82%), nonseasonal (82%), waxing/waning (36%) pruritus, with alopecia/crusting/excoriations and/or erosions/ulceration (73%). Miliary dermatitis (20%) and eosinophilic granuloma complex lesions (27%) occurred. The face/head (71%), ventral abdomen (51%), neck (51%), limbs (38%), pinnae (31%), dorsum/rump (31%) and feet (16%) were frequently affected sites; lesions were restricted to the head/neck in only five cats (11%). Concurrent otitis externa (16%), superficial bacterial pyoderma (49%), Malassezia dermatitis (7%), flea‐bite hypersensitivity (24%) and adverse food reaction (13%) occurred. Strong reactions on intradermal allergen testing were common (68%; 19 of 30), most frequently to pollens (61%) and/or insects (46%). Good response to ciclosporin (100%; 10 of 10), systemic glucocorticoids (55%; 22 of 40) and allergen‐specific immunotherapy (57%; 13 of 23) and good/partial response to antihistamines (67%; 22 of 33) were reported. CONCLUSIONS AND CLINICAL IMPORTANCE: The prevalence of feline AD was higher than previously suggested, and breed predispositions were confirmed. Severe nonseasonal pruritus was most common, with a varied spectrum of lesions affecting a range of body areas.