Feline viral papillomatosis: ABCD guidelines on prevention and management.

OVERVIEW Papillomaviruses are epitheliotropic and cause cutaneous lesions in man and several animal species, including cats. INFECTION Cats most likely become infected through lesions or abrasions of the skin. Species-specific viruses have been detected but human and bovine related sequences have also been found, suggesting cross-species transmission. CLINICAL SIGNS In cats, papillomaviruses are associated with four different skin lesions: hyperkeratotic plaques, which can progress into Bowenoid in situ carcinomas (BISCs) and further to invasive squamous cell carcinomas (ISCCs); cutaneous fibropapillomas or feline sarcoids; and cutaneous papillomas. However, papillomaviruses have also been found in normal skin. DIAGNOSIS Papillomavirus-induced skin lesions can be diagnosed by demonstration of papillomavirus antigen in biopsies of skin lesions, or detection of papillomavirus-like particles by electron microscopy and papillomavirus DNA by polymerase chain reaction (PCR). TREATMENT Spontaneous regression might be expected. In cases of ISCC, complete excision should be considered if possible.