From the beginning of recorded history, two mycobacterial diseases, leprosy and tuberculosis, have plagued mankind. Now infection by Mycobacterium ulcerans joins these as an important human disease. It occurs in limited areas of the tropics and subtrophics, where it poses a public health problem. In the March issue of the Archives of Pathology, Connor and Lunn1 describe the geographic distribution, clinical aspects, and pathologic features of this disease as it is seen in Uganda, East Africa.
Ulceration caused by M ulcerans was first recognized as a specific disease less than 20 years ago by MacCallum et al.2 How has it escaped general recognition for so long? There are two possible explanations. First, the disease is common only in remote areas of the Congo and Uganda, affecting, for the most part, rural peoples residing along the headwaters of the Congo River and along the upper reaches of the White