各種細菌による菌血症を繰り返しPR3-ANCA陽性を呈したMünchausen症候群の1例

Abstract

A 29-year-old woman chiropractor with repeated episodes of bacteremia and positive for cytoplasmic antineutrophil cytoplasmic antibody (c-ANCA) and antiproteinase-3 (PR3) antibody had an 11-year history of asthma and repeated hospitalization. While hospitalized she developed a spiking nocturnal fever with chills and erythema of the lower leg. Her fever resolved spontaneously, but corticosteroid therapy and antibiotics did not effectively reduce her symptoms. Plain X-ray film and CT showed pulmonary changes, and lung biopsy granulomas without vasculitis. Immunological studies showed a positive PR3-ANCA (c-ANCA) test, and skin biopsy of the crural erythema showed foreign body granuloma. Multiple blood cultures were positive for several strains of bacteria, including Fusobacterium necrophurum, Mycobacterium fortuitum, and Clostridium species. When placed in a single room and monitored, she did not develop new fever or erythema. Because self-injury was assumed, she was diagnosed as having Münchausen syndrome. This is, to our knowledge, the first report of Münchausen syndrome with PR3-ANCA positivity. In patients with repeated infections, the possibility of self-injury, the development of PR3-ANCA positivity, and pulmonary granuloma with a disease profile similar to vasculitis syndrome should be considered in the definitive diagnosis.