title: A simple method for assessing intestinal inflammation in Crohn's disease.
abstract: OBJECTIVE
  Assessing the presence and degree of intestinal inflammation objectively, simply, and reliably is a significant problem in gastroenterology. We assessed faecal excretion of calprotectin, a stable neutrophil specific marker, as an index of intestinal inflammation and its potential use as a screening test to discriminate between patients with Crohn's disease and those with irritable bowel syndrome.
  
  
  METHODS
  The validity of faecal calprotectin as a marker of intestinal inflammation was assessed in 22 patients with Crohn's disease (35 studies) by comparing faecal excretions and concentrations using four day faecal excretion of (111)indium white cells. A cross sectional study assessed the sensitivity of faecal calprotectin concentration for the detection of established Crohn's disease (n=116). A prospective study assessed the value of faecal calprotectin in discriminating between patients with Crohn's disease and irritable bowel syndrome in 220 patients referred to a gastroenterology clinic.
  
  
  RESULTS
  Four day faecal excretion of (111)indium (median 8.7%; 95% confidence interval (CI) 7-17%; normal <1.0%) correlated significantly (p<0.0001) with daily (median ranged from 39 to 47 mg; normal <3 mg; r=0.76-0.82) and four day faecal calprotectin excretion (median 101 mg; 95% CI 45-168 mg; normal <11 mg; r=0.80) and single stool calprotectin concentrations (median 118 mg/l; 95% CI 36-175 mg/l; normal <10 mg/l; r=0.70) in patients with Crohn's disease. The cross sectional study showed a sensitivity of 96% for calprotectin in discriminating between normal subjects (2 mg/l; 95% CI 2-3 mg/l) and those with Crohn's disease (91 mg/l; 95% CI 59-105 mg/l). With a cut off point of 30 mg/l faecal calprotectin has 100% sensitivity and 97% specificity in discriminating between active Crohn's disease and irritable bowel syndrome.
  
  
  CONCLUSIONS
  The calprotectin method may be a useful adjuvant for discriminating between patients with Crohn's disease and irritable bowel syndrome.
authors.affiliation: Department of Medicine, Guy's, King's, St Thomas' Medical School, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Tibble
authors.forename: K
authors.initials: K
authors.lastname: Teahon
authors.forename: B
authors.initials: B
authors.lastname: Thjodleifsson
authors.forename: A
authors.initials: A
authors.lastname: Roseth
authors.forename: G
authors.initials: G
authors.lastname: Sigthorsson
authors.forename: S
authors.initials: S
authors.lastname: Bridger
authors.forename: R
authors.initials: R
authors.lastname: Foster
authors.forename: R
authors.initials: R
authors.lastname: Sherwood
authors.forename: M
authors.initials: M
authors.lastname: Fagerhol
authors.forename: I
authors.initials: I
authors.lastname: Bjarnason
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D018957:CD59 Antigens / Q000032:analysis*; D003109:Colonic Diseases, Functional / Q000175:diagnosis; D003424:Crohn Disease / Q000175:diagnosis* / Q000276:immunology; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005243:Feces / Q000737:chemistry*; D005260:Female; D006801:Humans; D007205:Indium Radioisotopes; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D015415:Biomarkers; D018957:CD59 Antigens; D007205:Indium Radioisotopes