The period prevalence of oral lichen planus in a cohort of patients with vulvar lichen sclerosus.

BACKGROUND: Lichen sclerosus and lichen planus are chronic inflammatory mucocutaneous disorders that may coexist.

OBJECTIVE: The aim of this study was to estimate the period prevalence of oral lichen planus in a cohort of patients with vulvar lichen sclerosus and to document their clinical characteristics.

METHODS: We report a series of cases of vulvar lichen sclerosus presenting to two dermatologist-led vulvar clinics in Oxfordshire, England between 1997 and 2007 with coexistent clinical signs of oral lichen planus.

RESULTS: Thirteen cases with coexistent vulvar lichen sclerosus and oral lichen planus were identified, of which five had oral biopsies. Four oral biopsies showed histological features consistent with lichen planus. One oral biopsy was not diagnostic but compatible with oral lichen planus. No cases of oral lichen sclerosus were identified. The period prevalence of oral lichen planus was 6 per 1000 cases of vulvar lichen sclerosus.

CONCLUSION: The period prevalence of oral lichen planus in women with vulvar lichen sclerosus (0.6%) is similar to that reported for oral lichen planus in the general population (1-2%).