Two different human papillomavirus (HPV) types associated with oral mucosal lesions in an HIV-seropositive man

Different types of Human papillomaviruses (HPV) are associated with a variety of oral lesions. So far, HPV types 1, 2, 4, 6, 7, 11, 13, 16, 18, 32 and 57 have been identified in oral lesions. Immunosuppression predisposes oral mucosa to clinical manifestation of different virus infections including HPV. We describe here a 30-year-old HIV-positive and immunosuppressed man, who had suffered from oral lesions for a few months. On clinical examination, a nodular elevation was detected on the lower lip, and white keratotic areas were present on buccal mucosa bilaterally. A biopsy from the lip revealed the presence of acanthosis with a prominent granular cell layer as well as hyperparakeratosis. A biopsy from the buccal lesion showed a comparatively much flatter lesion with merely basal cell hyperplasia associated with hyperparakeratosis. Koilocytosis was a characteristic feature in both biopsies. In Southern blot hybridization, both lesions hybridized with a probe cocktail comprising HPV 6, 11, 16, 18, 31 and 33 DNA under low stringency. Under high stringency, the lip lesion proved to contain HPV 7 DNA, which also confirmed by in situ hybridization. The buccal lesion was weakly positive by Southern blot with HPV 11 and 13 probes hybridized under stringent conditions, but the restriction patterns with Pst I and Bam HI did not fit with those of any of the 57 HPV types known so far. In situ hybridizations with HPV 11 and HPV 13 probes were negative. Cloning of this 'new' HPV type is currently under way.