Vulvar vestibulitis. A histopathologic study of 36 cases, including human papillomavirus in situ hybridization analysis.

Vulvar vestibulitis is a recently described clinical condition of unknown etiology. Human papillomavirus (HPV) infection has been implicated as a causal pathogen by some investigators. Because reports on this entity are few, we studied the pathologic features of vestibulectomy specimens from 36 women with a clinical diagnosis of vulvar vestibulitis. The patients' ages ranged from 19 to 53 years (mean, 31 years). Bilateral excisions were performed in 34 patients and a unilateral excision in two. Minor vestibular glands or ducts were identified in 28 patients (78%). Chronic inflammation was present in all specimens. The inflammatory infiltrate consisted predominantly of T lymphocytes and plasma cells with smaller numbers of B lymphocytes. Lymphoid follicles were present in four patients, ulcers in two. The predominant site of inflammation was the squamous mucosa, especially the lamina propria, where the degree of inflammation was graded as mild in 11 patients, moderate in 21 patients, and severe in four patients. To a lesser degree, the inflammation also typically involved the periglandular/periductal connective tissue of the minor vestibular glands, where it was graded as mild in 25 patients and moderate in three patients. Foci of squamous metaplasia were observed in 27 of 28 patients with demonstrable vestibular ducts or glands. Nodular hyperplasia of a vestibular gland (so-called "adenoma") occurred in one patient. In six selected cases, fungi were not identified on silver stains. Morphologic findings of HPV infection, such as koilocytotic atypia or squamous dysplasia, were absent. In-situ hybridization studies for HPV types 6, 11, 16, 18, 31 and 35 were negative in all 36 cases. We conclude that (a) vestibulectomy specimens from patients with a clinical diagnosis of vulvar vestibulitis typically show a chronic inflammatory cell infiltrate that predominantly involves the mucosal lamina propria and periglandular/periductal connective tissue and (b) a pathogenetic role for HPV types 6, 11, 16, 18, 31 and 35 is not substantiated.