title: Multiple viral plaques with sebaceous differentiation associated with an unclassified papillomavirus type in a cat.
abstract: CASE HISTORY AND CLINICAL FINDINGS A 15-year-old neutered male domestic short-haired cat was presented due to multiple 0.5-2 cm-diameter crusting plaques in the left preauricular region, over the bridge of nose, and in the right periocular region. The plaques did not appear to cause discomfort. HISTOPATHOLOGICAL FINDINGS Biopsy samples of four plaques were examined histologically. Three plaques consisted of well-demarcated foci of mild epidermal hyperplasia overlying markedly hyperplastic sebaceous glands. Approximately 60% of the hyperplastic cells contained a large cytoplasmic vacuole that ranged from being clear to containing prominent grey-blue fibrillar material. The fourth plaque was composed solely of epidermal hyperplasia, consistent with previous descriptions of feline viral plaques. MOLECULAR BIOLOGY Papillomavirus DNA was amplified from all four plaques using PCR. A single DNA sequence was amplified from the plaques with sebaceous differentiation. This sequence was identical to the FdPV-MY sequence previously suggested to be from a putative unclassified papillomavirus type. Felis catus papillomavirus type 2 sequences were amplified from the plaque typical of feline viral plaques. Immunohistochemistry to detect p16CDKN2Aprotein (p16) showed marked immunostaining throughout the hyperplastic epidermis and adnexal structures within the plaques with sebaceous differentiation. DIAGNOSIS Multiple feline viral plaques with variable sebaceous differentiation. CLINICAL RELEVANCE Feline viral plaques with sebaceous differentiation have not been previously reported in cats. The presence of unique cell changes within these lesions, the detection of an unclassified papillomavirus type, and the p16 immunostaining within these plaques suggest that they may have been caused by the papillomavirus that contains the FdPV-MY sequence.
authors.affiliation: a Department of Pathobiology, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11 222, Palmerston North , New Zealand.
authors.forename: J S
authors.initials: JS
authors.lastname: Munday
authors.affiliation: b Veterinary Associates , Hastings , New Zealand.
authors.forename: S
authors.initials: S
authors.lastname: Marshall
authors.affiliation: a Department of Pathobiology, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11 222, Palmerston North , New Zealand.
authors.forename: N A
authors.initials: NA
authors.lastname: Thomson
authors.affiliation: c Department of Pathobiology and Diagnostic Investigation/Diagnostic Center for Population and Animal Health , Michigan State University , East Lansing , MI , USA.
authors.forename: M
authors.initials: M
authors.lastname: Kiupel
authors.affiliation: a Department of Pathobiology, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11 222, Palmerston North , New Zealand.
authors.forename: R W
authors.initials: RW
authors.lastname: Heathcott
authors.affiliation: d New Zealand Veterinary Pathology Ltd , Palmerston North , New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: French
mesh_terms: D000818:Animals; D002371:Cat Diseases / Q000175:diagnosis / Q000821:virology*; D002415:Cats; D017931:DNA Primers; D004279:DNA, Viral / Q000235:genetics; D005145:Face / Q000473:pathology; D007150:Immunohistochemistry; D008297:Male; D009520:New Zealand; D027383:Papillomaviridae; D030361:Papillomavirus Infections / Q000175:diagnosis / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012627:Sebaceous Glands / Q000473:pathology / Q000821:virology; D012867:Skin
chemical_list: D017931:DNA Primers; D004279:DNA, Viral
keywords: Bowenoid in situ carcinoma; Cat; dermatology; feline viral plaque; neoplasia; papillomavirus; skin