[The pediatric pelvic kidney--a retrospective analysis].
OBJECTIVES: We evaluated children with pelvic kidney and their follow-up according to initial renal function and the appearance of concomitant urological pathologies. PATIENTS AND METHODS: In a retrospective analysis of our case notes, we studied 17 children (8 female, 9 male) who had been referred to our department for further investigation between 1994 and 2002 in whom we found a pelvic ectopic kidney. RESULTS: The mean age of the patients at the initial investigation was 72.5 months (range, 2 - 156 months); 10/17 were referred to our department for further investigation and clarification of a suspected renal agenesis, the remaining 7/17 children presented with urinary tract infection (1/17), nocturnal enuresis (3/17), hypertension (1/17) and phimosis (2/17). The nuclear medicine scan performed at the initial investigation in 14/17 children revealed that the function of the ectopic kidney had been reduced to one-third in contrast to two-thirds for the orthotopic kidney (p = 0.002). Overall global renal clearance was normal in all children. In 8/17 patients, the ongoing control nuclear investigations, on average 26.2 months later, revealed unchanged overall function of the kidney, we did, however, find a slight improvement of the ectopic renal function as compared to initial investigation which was not statistically significant (p = 0.683). In the period of this retrospective analysis, surgical correction of an accompanying pathology was performed in 23.5 % (4/17) of the children (vesico-ureteteric reflux operation in two cases, surgery for pelvic ureteric junction obstruction in one case, and nephroureterectomy in one case of a nonfunctioning-kidney). A left-sided pelvic kidney was seen in 64.7 % (11/17) of cases, a right-sided ectopic kidney in 23.5 % (4/17), a pelvic fused kidney in 11.7 % (2/17), and a solitary left-sided pelvic ectopia with right-sided agenesis in 5.8 % (1/17) of cases. CONCLUSION: In the event of suspected renal agenesis on ultrasonography, the possibility of a pelvic ectopic kidney should always be included in the range of diagnoses. On ultrasonography, the pelvic kidney is best visualized inferior to the iliac vessels, in the presence of a filled bladder. It is more frequently encountered on the left side. Nearly one-thirds of our patients presented with concomitant pathologies and one quarter needed surgical intervention. Although the function of the ectopic kidney alone was reduced by (2/3), the overall renal clearance was normal and remained stable in the course of the observation period.