Nephron-sparing surgery in multiple bilateral angiomyolipomas.

We report on a 17-year-old white woman with multiple bilateral renal angiomyolipomas (AMLs) in the absence of tuberous sclerosis. Multiple hyperdense lesions were detected in both kidneys by sonography. A computed tomography (CT) scan confirmed mainly fatty tissue. Sparing as much functional tissue as possible, eight AMLs of the right kidney were resected. The largest removed tumour measured 7 x 4 x 2.4 cm. Renal function was completely preserved. An AML is a benign, generally unilateral renal tumour. Treatment is necessary in cases of flank pain, spontaneous bleeding, obstruction by tumour growth and tumours exceeding 4 cm in diameter. Patients who present are often symptomatic due to pain, retroperitoneal bleeding or haematuria. An AML occurs either sporadically or in association with tuberous sclerosis. Bilateral or unilateral multiple AMLs are rare.