The management of unilateral poorly functioning kidneys in patients with posterior urethral valves.

PURPOSE

There is no uniform agreement on how to manage the unilateral nonfunctioning or poorly functioning kidney associated with posterior urethral valves. We studied the results of treatment of our patients to make recommendations regarding management of these kidneys.

MATERIALS AND METHODS

We reviewed the records of 13 boys with a history of posterior urethral valves and a unilateral nonfunctioning or poorly functioning kidney, defined as less than 10% of total renal function on 99mtechnetium dimercapto-succinic acid renal scans. Variables investigated included pyelonephritis, hypertension, vesicoureteral reflux, nephroureterectomy, ureteral reimplantation and spontaneous cessation of reflux. We also evaluated how the management of abnormal urodynamic parameters influenced the results of reimplantation or medically induced cessation of reflux.

RESULTS

Three of the 6 boys with grade 5 reflux ipsilateral to the poorly functioning kidney required nephroureterectomy at a mean age of 21 months because of recurrent urinary tract infections. Another 4 boys underwent successful ureteral reimplantation, including 2 who had bilateral grade 5 reflux, and 2 who had ipsilateral grade 4 reflux, and grade 3 (1) and grade 2 (1) contralateral reflux. Of 4 boys ipsilateral grade 3 reflux in 3 and bilateral grade 5 reflux in 1 disappeared without surgery after treatment of urodynamic abnormalities. Two patients with poorly functioning kidneys and no reflux did not undergo surgery. Overall 10 of the 13 poorly functioning renal units were not removed, and these patients were free of pyelonephritis and hypertension. Ureteral reimplantation (4 ipsilateral and 3 contralateral) was performed only after urodynamic abnormalities were addressed. All reimplantations were successful.

CONCLUSIONS

Based on our results we believed that unilateral poorly functioning kidneys in patients with posterior urethral valves can be safely preserved in select patients without hypertension and pyelonephritis. Reimplantation to correct reflux may be preferable to nephroureterectomy in specific situations, such as when contralateral function is suboptimal and the contralateral ureter needs reimplantation. When indicated, reimplantation can be performed successfully if abnormal urodynamic parameters are addressed preoperatively. In fact, treating abnormal urodynamic findings may lead to spontaneous reflux resolution.