Abstract: 【Abstract】 A 58-year-old female patient presented with painful and itchy skin lesions on the head, neck, chest and back for 20 days, and was admitted to the hospital in February 2010. The skin lesions manifested as superficial erosions on an erythematous base with positive Nikolsky′s sign. Histopathological examination showed fissures above the granular and spinous cell layers, and scattered dyskeratotic cells. Direct immunofluorescence （DIF） assay revealed IgG and C3 deposits between spinous cells. The patient was initially diagnosed with pemphigus foliaceus. After the treatment with triamcinolone （24 mg/d）, tripterygium glycosides （60 mg/d）, nicotinamide （300 mg/d） and tetracycline （2 g/d）, skin lesions gradually subsided. In June 2017, the patient was readmitted due to itchy skin lesions on the head, neck, chest, back and hands for 15 days, which manifested as tense bullae on an erythematous base with negative Nikolsky′s sign. Histopathological examination showed subepidermal blisters and infiltration of eosinophils and lymphocytes in the blisters and superficial dermis, DIF assay revealed the deposition of IgG and C3 along the basement membrane zone, and enzyme-linked immunosorbent assay showed positive results for anti-BP180 antibody but negative results for anti-Dsg1 and Dsg3 antibodies. Then, a diagnosis of bullous pemphigoid was confirmed. The patient was treated with oral triamcinolone （12 mg/d）, nicotinamide （300 mg/d） and tetracycline （2 g/d）, and the lesions rapidly subsided.

Key words: Pemphigus, Pemphigus foliaceus, Convert, Bullous pemphigoid