We report the case of a 12 year-old girl who presented with acute renal failure with massive infiltration in both kidneys due to a Burkitt lymphoma that was diagnosed by percutaneous renal biopsy. This case fulfilled all the diagnostic criteria of Malbrain et al. to be considered as primary renal non-Hodgkin lymphoma. We discuss the differential diagnosis with other processes that present with acute renal failure and bilateral nephromegaly, and the mechanism by which renal failure occurs. It should be emphasised that this patient showed clinical symptoms compatible with rheumatic disease at diagnosis. The possibility of joint and muscle problems should be considered as a sign of onset of hematopoietic disease.