Clinical features of patients with solitary kidneys.

A clinical study was performed in 2 groups of patients with solitary kidneys, followed for 11-146 months. Group 1 had 9 patients (7 males and 2 females, aged between 23 and 68 years) with unilateral renal agenesis. Group 2 had 13 patients (9 females and 4 males, aged between 27 and 70 years) who underwent unilateral nephrectomy for the following reasons: hydronephrosis secondary to ureteropelvic junction stenosis, 7 patients; renal trauma, 4 patients; benign neoplasia, 2 patients. During the follow up, urinary protein excretion of more than 300 mg/day was observed in 9 patients, 3 in group 1 and 6 in group 2. Eleven patients, 8 in group 1 and 3 in group 2, were hypertensive (diastolic blood pressure higher than 95 mm Hg). Hyperuricemia was observed in 14 patients, 10 in group 1 and 4 in group 2. Seven patients, 4 in group 1 and 3 in group 2, had a significant deterioration of renal function. Neither proteinuria nor renal failure were observed before at least 10 years had elapsed since the anatomic condition of solitary kidney had been established. A surgical renal biopsy was performed in 1 patient with unilateral renal agenesis and showed focal glomerular sclerosis. This study adds support to the view that the reduction of 50% of the renal tissue may be a risky situation in humans as well as in animals.