[Bone lesions due to endemic African Kaposi sarcoma: a case report].

Based on clinical and epidemiological data Kaposi's sarcoma (KS) can be divided into four subtypes: classical KS, immunodepression-related KS (IKS), epidemic AIDS-associated KS (AKS), and endemic KS (EKS). EKS is the most common entity in intertropical Africa. The authors of this report describe a case of invasive KS of the extremities associated with metatarsal osteolysis in a 43-year-old man from Central Africa. The patient was seronegative for HIV. Osteolytic lesions associated with EKS are uncommon and present few specific symptoms. They are always associated with skin lesions and are sensitive to radiation therapy and/or systemic chemotherapy. With the growing HIV epidemic, the clinical features of EKS and AKS now overlap and distinction is no longer possible in Black Africa. However AKS rarely involves osteolytic lesions without unfavorable prognosis or unconventional therapeutic modalities. In patients who are seropositive for HIV, it is important to distinguish KS from bacillary angiomatosis. Since these two entities present similar clinical and radiological features, differentiation is usually achieved on the basis of histological findings but active therapeutic testing for bacillary angiomatosis may be necessary.