AIDS-associated nephropathy (AAN) causing acute renal failure has been described in patients with AIDS. It is characterized by massive proteinuria and focal segmental glomerulosclerosis. From 1982 until 1987, 177 patients with AIDS were seen in our center. Most of them were homosexual or bisexual men. One patient was also an intravenous drug addict. One patient was a black female. None suffered from a nephrotic syndrome or needed hemodialysis during their illness. In 47 of the 110 patients who died an autopsy was performed. On microscopical examination of kidney tissue obtained at autopsy, no abnormalities were seen in 12 patients and slight abnormalities were found in 35 patients. Glomerular changes, mostly fibrous caps in Bowman's space, were present in 22 patients. Mesangial and intracapillary lesions were seen in only 5 patients. Tubular atrophy was found in 14 patients and sparse interstitial inflammation in 15 patients. A renal localisation of disseminated opportunistic infections was found in 11 patients: CMV (n = 4), tuberculosis (n = 2), Mycobacterium avium intracellulare (n = 1) and Cryptococcal infection (n = 4). In one patient a renal localisation of a Kaposi sarcoma and in another patient a renal localisation of a disseminated non-Hodgkin lymphoma was found. In conclusion the clinical picture of AAN with acute renal failure was not found in our center. As is the case with heroin associated nephropathy, AAN seems to be confined to certain areas in the USA, suggesting that racial or local co-factors, are important for the pathogenesis of AAN in AIDS.