Does early pyeloplasty really avert loss of renal function? A retrospective review

We reviewed 75 cases of isolated, unilateral pediatric ureteropelvic junction obstruction and 167 diuretic radionuclide renograms performed during the last 8 years. Differential function of the affected kidney was calculated using scintillation count data at 1 and 3 minutes, and the area under the renogram curve between 1 and 3 minutes. There was no significant difference among the 3 measures of per cent differential function for a given patient. Per cent differential function on the first renogram preoperatively neither declined as age at presentation advanced nor did it vary according to the clinical presentation. Similarly, the changes in postoperative per cent differential function were unaffected by the age at initial presentation, manner of presentation, occurrence of postoperative complications or the surgeon. These data do not support the concept that pyeloplasty for the isolated, unilateral ureteropelvic junction obstruction should be performed early to avert loss of renal function.