We studied 28 consecutive patients (18 males and 10 females), 1-32 years of age, admitted to the intensive care unit from January 1989 to July 1995, with acute renal failure (ARF) due to meningococcal septicemia. All patients were treated with dexamethasone, penicillin, and/or chloramphenicol. Twenty-two patients presented septic shock and needed fluid replacement and vasoactive drugs. Acute renal failure was oliguric in 67.8%. Maximum levels of blood urea and serum creatinine were 210.3 +/- 26.6 mg/dL and 6.9 +/- 1.3 mg/dL, respectively. Metabolic acidosis was observed in 89.3% and hyperkalemia in 43%. The fractional excretion of sodium on day 1 was high (9.9 +/- 0.6%). The urinalysis did not show trace protein, but hematuria was positive in 81%. The mortality rate was 63.3%. In the 10 survivors, oliguria was present for a period of 12.7 +/- 2.4 days, and the period to reach a normal serum creatinine level was 20.2 +/- 4.7 days, although in two female patients, 7 and 17 years old, the elevated serum creatinine persisted. Renal biopsy was performed in one of these patients which revealed bilateral cortical necrosis. These data show that acute renal failure in meningococcemia presents high mortality rate associated to shock; 80% of the survivors recover renal function; and bilateral cortical necrosis occurred in one patient in this series.