[Histopathological examination of Buruli ulcer (Mycobacterium ulcerans disease) in surgically removed skin].

We report the results of an examination of gross images of two patients with Buruli ulcer and a histopathological evaluation of surgically removed skin from two other cases at the non-ulcerated and ulcerated stages, respectively. Histopathologically, dermal nodes were found in the non-ulcerated specimen; while wide necrosis of skin and fibrin deposition, as well as Langhans giant cell, epitheloid cells, and vasculitis, were observed in the ulcerated specimen, with granuloma in the lymph nodes. M. ulcerans was positive in a Fite stain and in a PGL-1 immunohistological stain. Based on these cases, we discuss the histological characteristics of Buruli ulcer.