A boy, aged 14 1/2 years, presented with Burkitt leukemia. His renal status was normal before treatment. Chemotherapy (SFOP LMB 86 protocol) was begun Oct. 9, 1986. After the first 2 courses of chemotherapy, the patient had Gram negative sepsis treated with cefotaxime, netilmycine, Vancomycin and ornidazole. During sepsis, nephrotic syndrome developed (albumin 25 g/l, non selective proteinuria 15 g/24 h), with moderately high blood pressure, functional renal failure (creatinine 141 mumols/l, U/P urea = 20), polyuria and tubular damage. Kidney ultrasonography was normal. Needle biopsy showed minimal glomerular lesions, acute tubular lesions, and no deposits in immunofluorescence. The nephrotic syndrome disappeared within 3 weeks, with treatment of leukemia. He is at present in complete remission with a follow-up of 25 months.