Histologic correlates of vulvar human papillomavirus infection in children and young adults.

Two clinically important issues in the treatment of vulvar wartlike lesions are the histologic criteria for the recognition of human papilloma virus (HPV)-related lesions and the exclusion of lesions derived from cutaneous rather than genital HPV types. We analyzed a series of 70 biopsies from the vulva or distal vagina of 57 children and 13 young adults for HPV nucleic acids by polymerase chain reaction (PCR) amplification and typed the isolates following isotope labeling and restriction digestion (restriction fragment length polymorphism [RFLP] analysis). Lesions were classified as condyloma, suggestive of condyloma (papillary/verrucous architecture without koilocytotic atypia), or nonspecific epithelial alterations. Three observers independently agreed on the presence of papillary/verrucous architecture and koilocytotic atypia with a high degree of concordance (kappa = 0.74 and 0.71, respectively). By RFLP analysis, 77% of the lesions diagnosed as condyloma and 68% of those diagnosed as suggestive of condyloma contained HPV nucleic acids versus 9% of the nonspecific group. The HPV types identified were HPV 6 (67%), HPV 11 (17%), HPV 16 (3%), and unknown types (14%). No cutaneous HPV types were identified. Three patients with unknown HPV types had a history of sexual abuse, implying a genital source. These findings indicate that verrucopapillary external genital lesions, as defined in this report, are likely to be associated with HPV and that the vast majority contain genital HPV types irrespective of histologic presentation.