Coexistent psoriasis and bullous pemphigoid responding to mycophenolate mofetil monotherapy.

A 73-year-old woman with a 50-year history of psoriasis was referred to our clinic with a 4-month duration of tense bullae on erythematous base and erosions localized on her lower extremities and torso (Figure 1A). Neither the oral nor the ocular mucosa had been involved. The lesions were intensively pruritic, significantly affecting the quality of her life. At the time of the examination, the patient presented with psoriatic plaques with adherent scales confined on the scalp (Figure 2A). According to the patient's history, her limited psoriasis was partially controlled with occasional topical medications (topical corticosteroids, calcipotriol, and tar shampoo). She also had insulin-dependent diabetes mellitus, asthmatic bronchitis, and partially controlled hypertension with hyperlipidemia. A biopsy specimen was taken from lesional skin on her feet, and a histological examination showed a subepidermal blister with an inflammatory cell infiltrate in the upper dermis. No drugs were incriminated, and diagnosis of bullous pemphigoid was confirmed by Western immunoblotting of serum. Laboratory investigation revealed mild thrombocytopenia of 110,000/mm(3), cholesterol 279 mg/dL, and triglycerides 210 mg/dL. The patient could not tolerate prednisolone and cyclosporine because of hypertension and diabetes, or azathioprine because of the mild thrombocytopenia; she did not consent to receiving biologics. Mycophenolate mofetil (MMF) was then considered a choice. The patient agreed, and she was initially administered 1000 mg/d. After 2 weeks, the dosage increased to 1000 mg twice a day because of the formation of new blisters. Within 8 weeks of treatment with MMF 2000 mg/d, marked improvement was observed and her pruritus resolved. Complete remission of bullous pemphigoid and psoriasis was achieved within 3 and 4 months, respectively. Routine laboratory studies were performed before treatment and every month during therapy, and MMF was tolerated without side effects. The treatment was continued for 6 months with no subsequent relapse of the dermatoses (Figure 1B and Figure 2B).