Abstract
We performed a retrospective histopathological study on the prevalence of hydropic degeneration of epidermal basal cells (strictly defined) in skin-biopsy specimens from 392 cats with various inflammatory dermatoses and 31 cats with normal skin. Hydropic degeneration of epidermal basal cells was significantly associated with a small group of immune-mediated dermatoses characterized by an interface dermatitis histopathological reaction pattern: adverse cutaneous drug reaction, discoid lupus erythematosus, erythema multiforme, exfoliative dermatitis associated with thymoma, and systemic lupus erythematosus. For this group of 5 diagnoses, the prevalence of hydropic degeneration was 35% (95% confidence interval [CI]: 16%, 59%); the other diagnoses had a prevalence of 1.1% (CI: 0.34%, 2.9%) and the healthy cats had a prevalence of 0% (CI: 0%, 14%).
