Diagnosis and treatment of a novel papillomavirus in a North American porcupine (Erethizon dorsatum)

Abstract

A nine-year-old sexually entire male North American porcupine (Erethizon dorsatum) was evaluated for multiple cutaneous masses that had progressively worsened over a seven-year period. Clinical examination revealed multiple exophytic pigmented papules, nodules and plaques on the muzzle, pinnae, limbs, palpebrae and periocular regions. Skin biopsies were consistent with papillomavirus-associated proliferative epithelial lesions. Using PCR primers specific for papillomaviruses, a partial fragment of the papillomavirus L1 gene was successfully amplified from the porcupine skin samples. Sequencing of the PCR product yielded a sequence with only 69% homology to the closest previously reported papillomavirus sequence, indicating this was a novel papillomavirus. Treatment was multimodal. A partial eyelid resection was performed, and a carbon dioxide laser and cryosurgery were used to treat focal lesions. Interferon-α 2A was also administered orally. These therapies resulted in a mild decrease in the size of the lesions followed by subsequent stabilisation over a period of 12 months.

Co-infection of distinct papillomavirus types in a captive North American porcupine

“…Conversely, it might also be that only one of the two viruses played a causal role in the clinical presentation, and that the detection of the second virus was no more than an accidental observation. Morphologically, the lesions seen here resembled those previously observed for EdPV-2 [ 10 ]. For EdPV-1, a comparison is more difficult because there are no images available of the only known EdPV-1 case.…”

“…Because the lesions resembled those of a papillomavirus infection (see [ 10 ]), DNA extract of one of the biopsies was screened for the presence of papillomavirus DNA using several previously published degenerate primer pairs targeting the conserved L1 or E1 regions of the genome (Table 1 ). However, all these screening assays failed to amplify part of a papillomavirus genome.…”

Histopathologic and molecular characterization of Erethizon dorsatum papillomavirus 1 and Erethizon dorsatum papillomavirus 2 infection in North American porcupines (Erethizon dorsatum)

“…EdPV2 infection was associated with a papilloma on the caudal dorsum in one porcupine, a location not previously reported for EdPV infection to the authors’ knowledge. 18,21,24,25 Remaining EdPV2 PCR-positive papillomas were distributed on the chin ( n = 1) and gingiva ( n = 1). An additional case fixed in a decalcifier solution that was suspected to reflect EdPV2 infection based on inclusion morphology was also located on the gingiva.…”

“…18,21,24 EdPV2 infection was additionally associated with intranuclear amphophilic and glassy material suggestive of viral inclusions within keratinocytes in the stratum spinosum and granulosum. 21…”

“…24 Virus-induced lesions were identified in all porcupines and included prominent keratohyalin granules and koilocytes, in addition to epidermal hyperplasia with orthokeratotic to parakeratotic hyperkeratosis. 18,21,24 EdPV2 infection was additionally associated with intranuclear amphophilic and glassy material suggestive of viral inclusions within keratinocytes in the stratum spinosum and granulosum. 21 Despite infection in the same host species, EdPV1 and EdPV2 are highly divergent.…”