Kaposi's sarcoma versus bacillary angiomatosis.

Persons with acquired immune deficiency syndrome (AIDS) are subject to a host of pathologic entities secondary to a depressed immune system. Kaposi's sarcoma frequently presents in this immunocompromised population and, therefore, diagnosis seems clinically straightforward. However, because of the prevalence of a strikingly similar infectious disease known as bacillary angiomatosis, skin biopsy of one or more lesions is crucial.