Presentation of two cases of renal abscess formation in patients with stage IV C-1 AIDS and active associated tuberculosis. The microorganism isolated in the first case was S. aureus. Culture of the second cases was artefacted since antibiotic administration had already been started. Also, both patients showed abdominal abscesses, at spleen and liver level in the first case, and prostatic level in the second case, both compatible with Mycobacterium tuberculosis dissemination. Both cases showed a lethal evolution. The role played by the immunodeficiency as a precipitating agent in the extrapulmonary tuberculosis and in the formation of renal abscesses is analyzed.