A case of bullous pemphigoid with initial onset in oral mucosa

Bullous pemphigoid is an autoimmune bullous disease occurring primarily in the skin, and initial onset in the oral mucosa is quite rare. A case of bullous pemphigoid with initial onset in the gingiva is reported. The patient was a 42-year-old female who presented with a primary complaint of recurrent gingival bullae that had appeared 9 months earlier. Enzyme-linked immunosorbent assay (ELISA) analysis of the patient's serum showed a positive reaction for anti-bullous pemphigoid 180 kDa antibodies (anti-BP180-NC16a antibodies). Immunohistochemical staining of a biopsy sample also revealed deposition of IgG and complement C3 in the basement membrane. With the use of an azulene gargle and topical application of a steroid ointment, the condition remained stable, but six weeks later, bullae also appeared around the navel, on the back, and on one lower leg. Use of a topical steroid ointment prescribed by a dermatologist was ineffective, so that, after one month, the patient was treated with oral administration of minocycline, and the symptoms in the mouth and skin improved. In this case, bullous pemphigoid with initial gingival onset was diagnosed at an early stage by ELISA analysis, and a satisfactory outcome was obtained without systemic use of steroid, which has commonly been used in the past.