AB143. SOH22ABS060. Plasma cell vulvitis or Zoon’s vulvitis

Background: Plasma cell vulvitis, or Zoon’s vulvitis, is a rare, benign, idiopathic, chronic inflammatory condition that affects the vulva. In 1952, Zoon reported a histological plasmacytic infiltrate, called balanitis plasma cellularis, which affected the penis and prepuce. Similar lesions identified in the vulva were reported by Garnier in 1954 and described as Zoon’s vulvitis. Case reports of this condition are rarely described in literature.

Methods: Case report: a 59-year-old female, para 5, attended the gynaecology outpatient department with a 1-year history of vulval irritation. She had tried several different treatments including antifungals, antibiotics and oestrogen creams with no response. She had changed several different washing powders and creams with no significant improvement. On examination she had excoriated, erythematous skin over the clitoral hood and extending into the labia on the right and left. A punch biopsy was taken under local anaesthesia. Histology showed features of a plasma cell rich lichenoid inflammatory infiltrate and is suggestive of a plasma cell vulvitis/Zoon’s vulvitis. She was trialled on dermovate ointment but showed minimal response after 6 weeks. Six weeks of further therapy showed significant improvement. However, some fusion of the labia was noted. The patient was referred to dermatology multidisciplinary team (MDT) for further discussion.

Results: Histology showed features of a plasma cell rich lichenoid inflammatory infiltrate and is suggestive of a plasma cell vulvitis/Zoon’s vulvitis.

Conclusions: It is uncommon. Plasma cell vulvitis typically exhibits a single unilateral, erythematous, sharply demarcated patch within the vestibule. Typically, Zoon’s vulvitis has the appearance of atrophic, shiny, erythematous plaques. Histologically, there will be an infiltrate of dense, subepithelial, mononuclear cells which are mainly plasma cells. Often patients will be asymptomatic, or may report mild itching/pain. Diagnosis is obtained histologically through biopsy of the lesion.

Keywords: Vulitis; Zoon’s vulvitis; plasma cell vulvitis; steroids treatment for vulvitis; vulval atrophic appearances