We present the case of a 55-year-old-man with AIDS who had disseminated Mycobacterium avium-intracellulare (MAI) infection who was nonadherent to antiretroviral treatment and prophylaxis for opportunistic infections. The patient acquired HIV via intravenous drug sue; he had a CD4+ cell count of 4/microL (1%) and an HIV RNA level of 114,000 copies/mL at the time of his HIV diagnosis. He presented with MAI bacteremia and had rapidly evolving and resolving cutaneous lesions caused by MAI. Concomitant nonspecific brain lesions presented a diagnostic challenge, but they improved with MAI treatment. In persons with HIV/AIDS who have cutaneous lesions, biopsy of superficial lesions has proved helpful. MAI infection should be considered in the differential diagnosis of cutaneous and brain lesions in persons with HIV/AIDS.