title: Factors affecting kidney function and stone recurrence rate after percutaneous nephrolithotomy for staghorn calculi: outcomes of a long-term followup.
abstract: OBJECTIVE
  There are few studies of the long-term outcome of percutaneous nephrolithotomy for staghorn calculi. We report the long-term outcome of percutaneous nephrolithotomy in patients with staghorn calculi.
  
  
  METHODS
  A total of 265 study patients (272 renal units) were followed in the long term for greater than 12 months. The estimated glomerular filtration rate was calculated using the 4-variable modification of diet in renal disease equation. Cases were staged for chronic kidney disease by National Kidney Foundation guidelines. The impact of patient and procedure related factors on renal function as well as stone recurrence was analyzed retrospectively.
  
  
  RESULTS
  At a mean ± SD followup of 37.3 ± 25.4 months the chronic kidney disease stage classification was maintained in 177 patients (66.8%) while the classification of 34 (12.8%) and 54 (20.4%) had improved and deteriorated, respectively. Multivariate analysis revealed that an immediate postoperative change in the estimated glomerular filtration rate was the only factor predicting a change in renal function in the long term. Stones recurred in 73 of the 234 kidneys (31.2%) that were stone free 3 months after percutaneous nephrolithotomy. Stone size increased in 24 of the 38 kidneys (63.2%) with residual stones after intervention. Recurrent urinary infections during followup and diabetes were associated with stone recurrence and residual stone enlargement.
  
  
  CONCLUSIONS
  In almost 80% of patients with staghorn stones renal function was improved or maintained after percutaneous nephrolithotomy, as documented during long-term followup. Stones recurred in a third of the patients with staghorn calculi.
authors.affiliation: Department of Urology, Haseki Training and Research Hospital, Istanbul, Turkey. takman36@gmail.com
authors.forename: Tolga
authors.initials: T
authors.lastname: Akman
authors.forename: Murat
authors.initials: M
authors.lastname: Binbay
authors.forename: Cem
authors.initials: C
authors.lastname: Kezer
authors.forename: Emrah
authors.initials: E
authors.lastname: Yuruk
authors.forename: Erdem
authors.initials: E
authors.lastname: Tekinarslan
authors.forename: Faruk
authors.initials: F
authors.lastname: Ozgor
authors.forename: Erhan
authors.initials: E
authors.lastname: Sari
authors.forename: Rahmi
authors.initials: R
authors.lastname: Aslan
authors.forename: Yalcin
authors.initials: Y
authors.lastname: Berberoglu
authors.forename: Ahmet Yaser
authors.initials: AY
authors.lastname: Muslumanoglu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D003404:Creatinine / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D007669:Kidney Calculi / Q000503:physiopathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects; D011183:Postoperative Complications / Q000453:epidemiology; D012008:Recurrence; D051436:Renal Insufficiency, Chronic / Q000453:epidemiology; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003404:Creatinine