title: Impact of retrograde flexible ureteroscopy and intracorporeal lithotripsy on kidney functional outcomes.
abstract: OBJECTIVE
  The aim of the study was to evaluate renal function and to identify factors associated with renal function deterioration after retrograde intrarenal surgery (RIRS) for kidney stones.
  
  
  METHODS
  We retrospectively analyzed patients with renal stones treated by RIRS between January 2010 and June 2013 at a single institute. We used the National Kidney Foundation classification of chronic kidney disease (CKD) to classify Glomerular Filtration Rate (GFR) in 5 groups. The baseline creatinine level was systematically pre-operatively and post-operatively evaluated. All patients had a creatinine blood measurement in June 2013. A change toward a less or a more favorable GFR group following RIRS was considered significant.
  
  
  RESULTS
  We included 163 patients. There were 86 males (52.8%) and 77 females (47.3%) with a mean age of 52.8±17 years. After a mean follow-up of 15.5±11.5 months, median GFR was not significantly changed from 84.3±26.2 to 84.9±24.5 mL/min (p=0.675). Significant renal function deterioration occurred in 8 cases (4.9%) and significant renal function amelioration occurred in 23 cases (14.1%). In univariate analysis, multiple procedures (p=0.023; HR: 5.4) and preoperative CKD (p=0.011; HR: 6.8) were associated with decreased renal function. In multivariate analysis these factors did not remain as predictive factors.
  
  
  CONCLUSIONS
  Stone management with RIRS seems to have favorable outcomes on kidney function; however, special attention should be given to patients with multiple procedures and preoperative chronic kidney disease.
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Hoarau
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Francois
authors.initials: F
authors.lastname: Martin
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Souhil
authors.initials: S
authors.lastname: Lebdai
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Chautard
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Thibaut
authors.initials: T
authors.lastname: Culty
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Abdel Rahmene
authors.initials: AR
authors.lastname: Azzouzi
authors.affiliation: Département d'urologie, Hôpital universitaire d'Angers, Angers, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Bigot
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000503:physiopathology*; D007669:Kidney Calculi / Q000503:physiopathology / Q000628:therapy*; D017602:Lithotripsy, Laser / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D059035:Perioperative Period; D011183:Postoperative Complications / Q000209:etiology / Q000503:physiopathology; D051436:Renal Insufficiency, Chronic / Q000209:etiology / Q000503:physiopathology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome; D018666:Ureteroscopy / Q000009:adverse effects / Q000379:methods*