title: The morphology and treatment of coexisting ureteropelvic junction obstruction in lower moiety of duplex kidney.
abstract: BACKGROUND
  Duplex kidney is a common congenital anomaly of the urinary tract, while ureteropelvic junction obstruction (UPJO) in lower unit of duplex kidney is rare. Surgical treatment can be challenging in such cases. The aim was to report our experience in managements of UPJO in lower moiety of duplex kidney.
  
  
  METHODS
  Among the pediatric patients with duplex system from 2007 to 2013, 7 children were diagnosed with UPJO in lower moiety. Their medical records were retrospectively analyzed, mainly focused on anatomic aspects and operation details.
  
  
  RESULTS
  The lower pole UPJO associated with incomplete duplex systems were identified in 6 patients on the left side and 1 on the right side. Median patient age at surgery was 11 months (range 6-84 months). Prenatal hydronephrosis was detected in 4 patients, and 3 had intermittent abdominal pain. Hydronephrosis, thin parenchyma and presence of UPJO in lower moiety could be shown on computed tomography urogram (CTU). The ureters were fused in a "Y" shape without any dilation. Based on the length between UPJO to the confluence in retrograde ureteropyelography, patients were classified into group 1 (5 cases,≤3 cm) and group 2 (2 cases, >3 cm). In group 1, surgical procedure involved end-to-side pyeloureterostomy of the lower pelvis to the ureteral confluence in 4 cases and laparoscopic pyeloureterostomy in one case. The two patients in group 2 underwent laparoscopic pyeloplasty of lower moiety. In all of these patients hydronephrosis gradually improved and no complications were detected during follow-up.
  
  
  CONCLUSIONS
  UPJO in a duplex kidney requires careful evaluation and treatment should be individualized. Ureteropyeloanastomosis is a feasible treatment for duplex kidneys associated to a functioning lower moiety with UPJO. With the technical improvements in laparoscopic pyeloplasty, this procedure can be performed using laparoscopy.
authors.affiliation: Department of Pediatric Surgery, Provincial Hospital Affiliated to Shandong University, 324 Jingwu Road, Jinan 250021, Shandong Province, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Pediatric Surgery, Provincial Hospital Affiliated to Shandong University, 324 Jingwu Road, Jinan 250021, Shandong Province, China.
authors.forename: Liujuan
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Shandong Medical Imaging Research Institute, 324 Jingwu Road, Jinan 250021, Shandong Province, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Ma
authors.affiliation: Department of Pediatric Surgery, Provincial Hospital Affiliated to Shandong University, 324 Jingwu Road, Jinan 250021, Shandong Province, China. Electronic address: wurd2006@aliyun.com.
authors.forename: Rongde
authors.initials: R
authors.lastname: Wu
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007668:Kidney / Q000002:abnormalities*; D007682:Kidney Pelvis / Q000601:surgery*; D010535:Laparoscopy; D008297:Male; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D014513:Ureter / Q000601:surgery*; D014517:Ureteral Obstruction / Q000601:surgery*; D013520:Urologic Surgical Procedures / Q000379:methods*
keywords: Child; Duplex kidney; Laparoscopy; Lower moiety; Pyeloureterostomy; Ureteropelvic junction obstruction