title: Fecal calprotectin predicts the clinical course of acute severe ulcerative colitis.
abstract: OBJECTIVE
  Calprotectin is a granulocyte neutrophil-predominant cytosolic protein. Fecal concentrations are elevated in intestinal inflammation and may predict relapse in quiescent inflammatory bowel disease. We aim to investigate fecal calprotectin (FC) as a biomarker in predicting the clinical course of acute severe ulcerative colitis (ASUC).
  
  
  METHODS
  In 90 patients with ASUC requiring intensive in-patient medical therapy (January 2005-September 2007), we investigated the discriminant ability of FC to predict colectomy and corticosteroid and infliximab nonresponse. All patients received parenteral corticosteroids as first-line treatment; 21 (23.3%) were also treated with infliximab (5 mg/kg), after failure of corticosteroid therapy.
  
  
  RESULTS
  Of 90 patients, 31 (34.4%) required colectomy, including 11 (52.4%) of those treated with infliximab. Overall FC was high (1,020.0 microg/g interquartile range: 601.5-1,617.5). FC was significantly higher in patients requiring colectomy (1,200.0 vs. 887.0; P=0.04), with a trend toward significance when comparing corticosteroid nonresponders and responders (1,100.0 vs. 863.5; P=0.08), as well as between infliximab nonresponders and responders (1,795.0 vs. 920.5; P=0.06). Receiver-operator characteristic curve analysis yielded an area under the curve of 0.65 to predict colectomy (P=0.04), with a maximum likelihood ratio of 9.23, specificity 97.4%, and sensitivity 24.0% at a cutoff point of 1,922.5 microg/g. Kaplan-Meier analyses showed that using 1,922.5 microg/g over a median follow-up of 1.10 years, 87% of patients will need subsequent colectomy.
  
  
  CONCLUSIONS
  This is the first data set to demonstrate that FC levels are dramatically elevated in severe UC. These data raise the possibility that this biomarker can predict response to first or second-line medical therapy in this setting.
authors.affiliation: Western General Hospital, University of Edinburgh, UK. gwotzerho@aol.co.uk
authors.forename: G T
authors.initials: GT
authors.lastname: Ho
authors.forename: H M
authors.initials: HM
authors.lastname: Lee
authors.forename: G
authors.initials: G
authors.lastname: Brydon
authors.forename: T
authors.initials: T
authors.lastname: Ting
authors.forename: N
authors.initials: N
authors.lastname: Hare
authors.forename: H
authors.initials: H
authors.lastname: Drummond
authors.forename: A G
authors.initials: AG
authors.lastname: Shand
authors.forename: D C
authors.initials: DC
authors.lastname: Bartolo
authors.forename: R G
authors.initials: RG
authors.lastname: Wilson
authors.forename: M G
authors.initials: MG
authors.lastname: Dunlop
authors.forename: I D
authors.initials: ID
authors.lastname: Arnott
authors.forename: J
authors.initials: J
authors.lastname: Satsangi
mesh_terms: D000208:Acute Disease; D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D015415:Biomarkers / Q000032:analysis; D003082:Colectomy; D003093:Colitis, Ulcerative / Q000175:diagnosis* / Q000378:metabolism / Q000628:therapy; D005243:Feces / Q000737:chemistry*; D005260:Female; D005765:Gastrointestinal Agents / Q000627:therapeutic use; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D000069285:Infliximab; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D005765:Gastrointestinal Agents; D005938:Glucocorticoids; D039841:Leukocyte L1 Antigen Complex; D000069285:Infliximab