title: Clinical evaluation of urolithiasis in Crohn's disease.
abstract: OBJECTIVE
  To investigate the characteristics of urolithiasis associated with Crohn's disease in a Japanese population.
  
  
  METHODS
  We studied 98 patients with Crohn's disease: 39 with urolithiasis and 59 without urolithiasis. Patients were treated at the Social Insurance Central General Hospital, or at the Toho University Omori, Ohashi, or Sakura Medical Centers.
  
  
  RESULTS
  Calculi were more frequent in men (n = 30) than women (n = 9). Mean time from diagnosis of Crohn's disease to diagnosis of calculi was 8.8 years (range 0 to 22 years). Calculi were present on the right side in 19 patients and the left side in 19 patients. Stone were composed of calcium oxalate in nine patients, calcium oxalate and calcium phosphate in two patients, and ammonium urate in five patients. The rate of concurrent calculi was significantly higher in ileostomates. The probability of developing calculi was approximately eight times higher for patients with a urine pH of <or=6.0 than for those with a urine pH of >or=6.5.
  
  
  CONCLUSIONS
  The rate of concurrent urolithiasis was higher in patients with a urine pH of <or=6.0, ileostomy, or two or more bowel resections. To prevent formation of calculi, Crohn's disease patients require regular urological examination including urinalysis, ultrasonography, and kidney ureter bladder X-ray.
authors.affiliation: Department of Urology, Toho University School of Medicine, Tokyo, Japan. gen-93013@sakura.med.toho-u.ac.jp
authors.forename: Genichi
authors.initials: G
authors.lastname: Ishii
authors.forename: Kouichi
authors.initials: K
authors.lastname: Nakajima
authors.forename: Norie
authors.initials: N
authors.lastname: Tanaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hara
authors.forename: Moriaki
authors.initials: M
authors.lastname: Kato
authors.forename: Nobuhisa
authors.initials: N
authors.lastname: Ishii