FUNCTIONAL RESULTS OF PYELOPLASTY IN PATIENTS WITH ANTE-NATALLY DIAGNOSED PELVI-URETERAL JUNCTION OBSTRUCTION

Objective To assess the outcome after pyeloplasty in children with an ante-natal diagnosis of hydronephrosis, shown on post-natal renography to be due to pelvi-ureteric junction (PUJ) obstruction, and in partic ular to review the outcome of those who had initially been managed exp ectantly, Patients and methods Between 1984 and 1995, 321 patients wer e diagnosed as having PUJ obstruction, after investigating ante-natal hydronephrosis. Of these, 47 had undergone pyeloplasty and also had a normal contralateral kidney: 26 patients had early pyeloplasty because of impaired function and 21 underwent surgery after a period of expec tant management, Renal function was assessed renographically before an d at least one year after surgery. Results Relative renal function was stabilized in those patients who underwent early pyeloplasty (mean di fferential function 28.1% before and 32.7% after surgery). In patients who underwent pyeloplasty after a period of expectant management, the mean relative function decreased from 44.8% initially to 30.5% before surgery: this recovered to 37.5% at the postoperative reassessment, r epresenting a statistically significant loss of function (P < 0.01). C onclusion In patients born with PUT obstruction and impaired renal fun ction, pyeloplasty failed to significantly improve function, possibly because of cortical loss. In patients with ante-natal PUJ obstruction managed expectantly there is a small but significant risk of a modest loss of renal function.