Subcutaneous abscess formation in the upper extremity caused by toxigenic Corynebacterium ulcerans

Corynebacterium ulcerans is attracting attention as an emerging zoonosis that causes lymphadenitis, dermatitis and respiratory infections. We report here what appears to be the first case of subcutaneous abscess formation in the upper extremity due to toxigenic C. ulcerans in Japan. Awareness of the fact that C. ulcerans can cause a subcutaneous, elastic-hard, less-mobile mass with heat, redness and pain in the extremities is important for differential diagnosis.