Aetiological factors in vulvar dermatitis

To determine aetiological factors in vulvar dermatitis.

Dermatitis of the vulva is a common clinical diagnosis in the specialized vulva clinic, although the exact prevalence is unknown. Aetiological factors are poorly understood in particular the incidence of atopy and seborrhoeic dermatitis. Other factors implicated are iron deficiency and exogenous causes such as contact irritants and allergens.

During a 1-year period, 38 patients with an initial clinical diagnosis of vulvar dermatitis were questioned, examined and investigated with full blood count, serum ferritin, bacterial swab where indicated and punch biopsy. After three patients had been excluded with other diagnoses, prick testing and patch testing were carried out.

Of the 35 patients with vulvar dermatitis, 34 (97%) had either an atopic background and/or seborrhoeic dermatitis. Iron deficiency occurred in seven patients (20%) and relevant positive patch tests in nine patients (26%). Twenty patients had biopsies and all had confirmatory histology.

This study suggests that the main aetiological factor in vulvar dermatitis is an endogenous predisposition. Iron deficiency may also contribute, while contact with irritants and allergens may explain the localization and frequently complicates and exacerbates the picture. Secondary sensitization to multiple substances is common.