Pyodermatitis–pyostomatitis vegetans after subtotal colectomy for ulcerative colitis

A 51‐year‐old Japanese woman underwent subtotal colectomy for ulcerative colitis 5 years before her first visit to our hospital, and her symptoms stabilized. She presented with a 2‐month history of proliferative, pustular lesions on her face, scalp, and gingival and anal mucosae. Histological examination showed features similar to those of pemphigus vegetans. However, the results of immunofluorescence studies, immunoblot analysis and enzyme‐linked immunosorbent assay for pemphigus were negative, and colonoscopy revealed a relapse of ulcerative colitis in the remaining rectal mucosa, so a diagnosis of pyodermatitis–pyostomatitis vegetans was made. This is the first report of mucocutaneous lesions that developed with a relapse of ulcerative colitis in the remaining rectum after subtotal colectomy. Moreover, a close correlation was found between the condition of bowel inflammation and that of mucocutaneous lesions.