Outcomes and fate of the remnant moiety following laparoscopic heminephrectomy for duplex kidney: a multicenter review.
PURPOSE
To evaluate outcomes following laparoscopic heminephrectomy (LHN) in duplex kidneys in the pediatric population, focusing on the fate of the remnant moiety.


METHODS
142 patients underwent laparoscopic heminephrectomy for duplex kidney across 4 different institutions in the U.S. and Europe. Median age at surgery was 11.4 months. A retroperitoneoscopic approach was used in all patients, with 82 (57.7%) patients placed in posterior prone position (PPR), and 60 (42.3%) in lateral retroperitoneal (LRP). Follow up included routine ultrasound, and DMSA was performed in the event of abnormalities in ultrasound or postoperative course.


RESULTS
Median operative time was 120 min. 11 patients (7.7%) required open conversion, the majority of which (8/11) occurred prior to 2000. Median hospital stay was 2 days and no major complications were observed. 7 patients (4.9%) developed a postoperative urinoma, and 1 patient required ureterectomy for urinary tract infection. With a median follow-up of 4.5 years, 7 children (4.9%) experienced significant loss of function in the remaining moiety, with 3 patients requiring completion nephrectomy. Of patients losing their remaining moiety, median age at surgery was 9 months [4 - 42], and all except 1 (6/7) had an upper pole heminephrectomy. Three patients in this group (42%) experienced an immediate postoperative complication (hematoma, UTI, urinoma). No consistent preoperative or technical factors were consistent in the renal loss group.


CONCLUSIONS
LHN for duplex kidney produces satisfactory outcomes in the pediatric population. With a median follow up of 4.5 years, we demonstrate a non-functioning renal moiety rate of 5%. We did not identify any clinical predictors of this outcome in our series, although upper pole heminephrectomy, patient age, and postoperative complications may be contributing factors.