Secondary polycythaemia associated with bilateral renal lymphocoeles.

A patient with a 15 year history of secondary polycythaemia due to renal erythropoietin hypersecretion is presented. Subsequent spontaneous development of bilateral renal lymphocoeles, which contained high erythropoietin levels, was shown by computerized tomography. The lymphocoeles were successfully treated by bilateral peritoneal marsupialization. No cause for the persistent polycythaemia or lymphocoeles was found at laparotomy or on renal biopsy.