title: Colonic perforation during percutaneous nephrolithotomy: study of risk factors.
abstract: OBJECTIVE
  To identify the risk factors implicated in colonic perforation during percutaneous nephrolithotomy.
  
  
  METHODS
  From 1985 to 2004, 5039 percutaneous nephrolithotomy procedures were performed in our center. Colonic perforation complicated 15 procedures (0.3%). The patient files were retrospectively reviewed for detection of preoperative risk factors as shown by multivariate statistical analysis. The operative details and postoperative course were also studied to determine the time and mode of diagnosis of colonic injury and treatment strategies and outcome.
  
  
  RESULTS
  All injuries were retroperitoneal. The mean patient age was 57 +/- 8.4 years. Of the 15 patients, 11 were men and 4 were women. The left side was affected in 10 patients (66.6%). The right side was injured only in those with horseshoe kidneys or with recurrent disease. Colonic perforation complicated lower caliceal puncture in 12 procedures (80%) and complicated upper caliceal punctures in those with horseshoe kidneys or chronic colonic distension. Significant independent risk factors were advanced patient age and the presence of a horseshoe kidney. The diagnosis was established intraoperatively in 5 patients and postoperatively in 10, 5 of whom presented with colocutaneous fistula. The diagnosis was confirmed with abdominal computed tomography or opacification of the colon during antegrade or retrograde pyelography. Conservative treatment was successful in all but 2 patients who required colostomy.
  
  
  CONCLUSIONS
  Significant independent risk factors for colonic perforation during percutaneous nephrolithotomy were advanced patient age and the presence of a horseshoe kidney. Early diagnosis and proper treatment represent the key to minimizing patient morbidity and avoiding serious complications.
authors.affiliation: Department of Urology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt.
authors.forename: Ahmed R
authors.initials: AR
authors.lastname: El-Nahas
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Shokeir
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: El-Assmy
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Shoma
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Eraky
authors.forename: Mahmoud R
authors.initials: MR
authors.lastname: El-Kenawy
authors.forename: Hamdy A
authors.initials: HA
authors.lastname: El-Kappany
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D003108:Colonic Diseases / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D005260:Female; D006801:Humans; D007416:Intestinal Perforation / Q000175:diagnosis / Q000209:etiology* / Q000628:therapy; D007668:Kidney / Q000002:abnormalities; D007669:Kidney Calculi / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome