title: Preoperative urinary tract obstruction in scoliosis patients.
abstract: BACKGROUND
  While the association between scoliosis and cardiac and respiratory function impairments has been well characterized in clinical practice and research, the potential effect of scoliosis on urinary tract structure and renal function has received little attention. Therefore, the purpose of this study was to evaluate the preoperative clinical characteristics of urinary tract structure and renal function in pediatric patients with idiopathic scoliosis, using a combination of blood tests, urinalysis, and imaging.
  
  
  METHODS
  Preoperative measures of urinary tract structure and renal function were obtained for 16 patients, 13-17 years old, scheduled for corrective surgery for idiopathic scoliosis. Preoperative assessment included blood test and urinalysis, combined with structural imaging on ultrasound (US), magnetic resonance imaging (MRI), magnetic resonance urography (MRU), and radioisotope tracing (RI), using technetium-99 m mercaptoacetyltriglycine (99mTc-MAG3). Differences in blood and urine tests between patients with and without urinary tract obstruction (UTO) were evaluated for significance using Mann-Whitney U test.
  
  
  RESULTS
  For all 16 patients, blood tests and MRU were within normal limits. Dilatation of the renal pelvis was identified on US in eight patients (50.0%). UTO was identified on RI in six patients (37.5%). UTO was associated with elevated β2-microglobulin concentration. Urinary β2-microglobulin concentration >0.7 μg/mg Cr differentiated patients with UTO from those without UTO, with a sensitivity of 100% and specificity of 70%.
  
  
  CONCLUSIONS
  β2-Microglobulin concentration may be a useful marker to screen for asymptomatic UTO in patients with idiopathic scoliosis.
authors: Department of Pediatrics, Seirei Sakura Citizen Hospital, Sakura, Chiba, Japan.
authors: Shigeru
authors: S
authors: Suzuki
authors: Department of Orthopedic Surgery, Seirei Sakura Citizen Hospital, Sakura, Chiba, Japan.
authors: Toshiaki
authors: T
authors: Kotani
authors: Department of Pediatrics, Seirei Sakura Citizen Hospital, Sakura, Chiba, Japan.
authors: Kazuetsu
authors: K
authors: Mori
authors: Department of Pediatrics, Seirei Sakura Citizen Hospital, Sakura, Chiba, Japan.
authors: Ken
authors: K
authors: Kawamura
authors: Department of Pediatrics, Faculty of Medicine, Saitama Medical University, Saitama, Japan.
authors: Akira
authors: A
authors: Ohtake
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000652:urine; D002648:Child; D005260:Female; D006801:Humans; D007677:Kidney Function Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D057234:Preoperative Period; D011446:Prospective Studies; D012600:Scoliosis / Q000150:complications* / Q000601:surgery; D017263:Technetium Tc 99m Mertiatide / Q000008:administration & dosage; D014517:Ureteral Obstruction / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery / Q000652:urine; D014551:Urinary Tract / Q000473:pathology*; D014567:Urography; D001613:beta 2-Microglobulin / Q000652:urine
chemical_list: D015415:Biomarkers; D001613:beta 2-Microglobulin; D017263:Technetium Tc 99m Mertiatide
keywords: obstructive uropathy; radioisotope; urinary tract obstruction; β2-microglobulin/creatinine concentration ratio in urine idiopathic scoliosis