A Case of Pemphigus Foliaceus Initially Presented with Seborrheic Dermatitis and Recurred with Neutrophic Pustules

Abstract

An 85-year-old man presented with severe scaly erythema on his left cheek. The symptoms gradually worsened despite topical steroid treatment and spread to the trunk and buttock, leaving vesicles and erosions. There were no mucosal lesions. Direct immunouorescence staining showed deposition of IgG on the intercellular surface of keratinocytes, and high titres of IgG antibodies to desmoglein 1 were obtained, but not to desmoglein 3. We made a diagnosis of pemphigus foliaceus and started oral predonisolone treatment. The symptoms improved ; however,the pustular skin lesions recurred when the dose of predonisolone was reduced. Histopathological examination showed formation of subcorneal pustules containing many neutrophils with a few acantholytic keratinocytes mimicking Kogoj’s spongiform pustules. Based on the increased titres of IgG antibodies to desmoglein 1, we prescribed a higher dose of predonisolone, and the symptoms subsided immediately. There are some similar case reports of pemphigus foliaceus with prominent neutrophic pustular skin lesions ; however, the causative mechanism of the accumulation of neutrophils and the pustule formation remains to be elucidated. The present case reconrms the importance of direct immunouorescence staining and taking titres of IgG antibodies to desmoglein 1 for following up patients with pemphigus foliaceus. Skin Research, 22 : 13-18, 2023