title: Ureteroscopy for nephrolithiasis in transplanted kidneys.
abstract: BACKGROUND
  While percutaneous nephrolithotomy (PCNL) is often the procedure of choice for renal and ureteral calculi in transplant kidneys, retrograde ureteroscopy (URS) is a less frequently applied but excellent option if stone burden is small. We retrospectively examined nine surgical cases performed in seven patients in what appears to be the largest single institutional series reported to date.
  
  
  METHODS
  Seven patients underwent nine retrograde URS between June of 2009 and September of 2013, by two endourologists. These cases were reviewed retrospectively.
  
  
  RESULTS
  Among the nine procedures, we were able to address the stone(s) endoscopically in seven. Among these procedures, laser lithotripsy was used in six cases, and basket stone extraction was applied in four procedures. Ureteral stents were placed following six procedures with ureteral access and treatment. Postoperative imaging revealed the patient to be stone free after five of the seven procedures with ureteral access and treatment. There were two postoperative urinary tract infections, and no major complications. Of the nine total procedures, six were outpatient, two were followed by observation stay < 24 hours, and one patient was admitted > 24 hours. Among the two failures, one underwent PCNL and the other had percutaneous nephrostomy (PNT) placed but expired from unrelated causes prior to the intended PCNL.
  
  
  CONCLUSIONS
  Retrograde URS with laser lithotripsy and/or basket extraction is a reasonable option for treating small renal transplant stones, with most patients in our series being discharged as outpatients, having complete stone clearance and avoiding PCNL.
authors.affiliation: University of Michigan Health System, Ann Arbor, Michigan, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: Swearingen
authors.forename: William W
authors.initials: WW
authors.lastname: Roberts
authors.forename: J Stuart
authors.initials: JS
authors.lastname: Wolf
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000000981:diagnostic imaging / Q000473:pathology*; D016030:Kidney Transplantation; D017602:Lithotripsy, Laser; D008297:Male; D008875:Middle Aged; D053040:Nephrolithiasis / Q000175:diagnosis* / Q000628:therapy*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014463:Ultrasonography; D018666:Ureteroscopy / Q000009:adverse effects / Q000379:methods*; D014552:Urinary Tract Infections / Q000453:epidemiology