Retrospective histopathologic reevaluation of 18 cases of plasma cell vulvitis.

To determine some common histologic features in a series of plasma cell vulvitis (PCV) cases.In a retrospective study, 18 histologic sections, previously obtained by vulvar biopsy in women diagnosed as having PCV, were critically reevaluated by the same pathologist.We observed that plasma cells in the dermal infiltrate were frequently present in a high percentage. Hemosiderin deposition and epithelial atrophy were 2 other histologic parameters useful for the diagnosis of PCV. Lozenge-shaped keratinocytes were rarely observed.In our series of PCV the percentage of plasma cells seemed to be the most important parameter when making the diagnosis. In particular, when this percentage was > or = 50% it was a sufficient histologic parameter for a diagnosis of PCV. When the percentage was 25-50%, hemosiderin deposition and epithelial atrophy were additional histologic features helpful in diagnosing PCV. Under 25% plasma cells was nonspecific and related to the mucosal site of involvement.