Impaired differential renal function in a child with pheochromocytoma.

We report a girl with extra-adrenal pheochromocytoma complicated with impaired renal function of the ipsilateral kidney, discussing aetiologies. A 14-year-old girl presented with uncontrolled hypertension, high urinary vanillylmandelic acid level and a 5 x 6 cm mass at the right renal hilum. Her blood pressure was under control with propranolol, prazosin, and nifedipine before surgery, and with sodium nitroprusside during surgical intervention. The total tumour removal required reconstruction of the right renal vein. Histopathology confirmed pheochromocytoma. Dimercaptosuccinic acid (DMSA) after surgery showed low uptake of isotope by the right kidney; it was unclear if this was due to the surgery or the tumour causing renal artery stenosis, but fortunately her blood pressure returned to normal thereafter. We recommend obtaining a DMSA in the preoperative evaluation of pheochromocytoma.