Renin-secreting juxtaglomerular tumor causing severe hypertension: diagnosis by computerized tomography-directed needle biopsy.

Renin-secreting tumors are a rare cause of severe hypertension accompanied by hypokalemia. Typically, these tumors have been difficult to diagnose preoperatively by standard radiographic and hormonal studies. We describe a 44-year-old man who was hospitalized for paroxysmal hypertension and who had a 2.3 cm. mid upper pole renal mass on sonography. Computerized tomography-directed needle biopsy revealed a juxtaglomerular tumor and surgical excision of the tumor was curative. We discuss the unique diagnostic aspects of this case.