title: Cystine stones: a single tertiary center experience.
abstract: OBJECTIVE
  To analyze the epidemiological and clinical characteristics and therapeutic outcomes of patients with cystine stones and to compare them with the characteristics of patients with calcium oxalate stones.
  
  
  METHODS
  We identified 30 patients with cystine stones who were consulted in our department from January 1972 until December 2013. These patients were matched and paired, based on age and gender, to 30 calcium oxalate stone formers who were diagnosed and treated in our department from January 2011 until December 2013.
  
  
  RESULTS
  Cystine stones were significantly large in size (p<0.001) and most of them were found in the kidney (p=0.002). Patients with cystinuria had their first stone episode at an early age (p<0.001) compared with patients with calcium oxalate stones. No significant differences were observed regarding the frequency and the severity of symptoms. Both groups had similar visits per year in outpatient clinics, emergency room admissions, and episodes of febrile urinary tract infections. Cystine stone formers had undergone significantly higher number of procedures for stone removal (p<0.001). No statistical differences were found in the compliance rates between the groups. Patients with cystine stones had significantly higher serum creatinine levels (p=0.005).
  
  
  CONCLUSIONS
  Cystine stones present in an earlier age and have the likelihood to be large in size. Patients with cystine stones undergo a greater number of procedures, and they have a greater risk to develop chronic renal impairment.
authors.affiliation: 1 Urology Department, Hadassah University Hospital , the Hebrew University, Jerusalem, Israel .
authors.forename: Stavros
authors.initials: S
authors.lastname: Sfoungaristos
authors.forename: Rony
authors.initials: R
authors.lastname: Hakim
authors.forename: Ran
authors.initials: R
authors.lastname: Katz
authors.forename: Ofer N
authors.initials: ON
authors.lastname: Gofrit
authors.forename: Ezekiel H
authors.initials: EH
authors.lastname: Landau
authors.forename: Vladimir
authors.initials: V
authors.lastname: Yutkin
authors.forename: Dov
authors.initials: D
authors.lastname: Pode
authors.forename: Mordechai
authors.initials: M
authors.lastname: Duvdevani
mesh_terms: D000328:Adult; D017668:Age of Onset; D002129:Calcium Oxalate; D016022:Case-Control Studies; D003553:Cystine; D003555:Cystinuria / Q000453:epidemiology* / Q000628:therapy; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry* / Q000453:epidemiology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014545:Urinary Calculi / Q000737:chemistry / Q000453:epidemiology / Q000628:therapy; D014552:Urinary Tract Infections / Q000209:etiology
chemical_list: D002129:Calcium Oxalate; D003553:Cystine