title: Comparison of three tests for faecal calprotectin in children and young adults: a retrospective monocentric study.
abstract: OBJECTIVE
  Faecal calprotectin is used as a sensitive marker for gastrointestinal mucosal inflammation. We compared the performance of three different assays in a large cohort of symptomatic paediatric patients.
  
  
  METHODS
  Retrospective monocentric study.
  
  
  METHODS
  Inpatients and outpatients of a tertiary referral centre for paediatric gastroenterology.
  
  
  METHODS
  304 symptomatic patients (163 males, aged 2-20 years) with active inflammatory bowel disease (IBD/A, n=130), IBD in clinical remission (IBD/R, n=62), other intestinal diseases (n=45) and controls without identified intestinal disease (n=67).
  
  
  METHODS
  Calprotectin was measured in homogenised faecal samples with three tests (A: EliA Calprotectin, Phadia AB, Sweden; B: PhiCal, Calpro AS, Norway; C: EK-Cal, Bühlmann Laboratories, Switzerland).
  
  
  RESULTS
  Concordance between tests was calculated using Kendall's τ coefficient.
  
  
  RESULTS
  IBD/A and controls were correctly classified as 97.7%/82.1% (A), 97.7%/85.1% (B) and 98.4%/62.7% (C; not significant). Test C tended to have higher calprotectin values with a lower specificity compared to tests A and B. The concordance between two tests was 0.835 for tests A and B, 0.782 for tests A and C and 0.765 for tests B and C.
  
  
  CONCLUSIONS
  All three tests are very sensitive for detecting mucosal inflammation, but major differences exist between specificity and absolute values. It is highly advisable to use the test of the same manufacturer for follow-up and to monitor for disease activity.
authors.affiliation: Division of Paediatric Gastroenterology and Hepatology, Dr. v. Haunersches Kinderspital, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Prell
authors.forename: Dorothea
authors.initials: D
authors.lastname: Nagel
authors.forename: Folke
authors.initials: F
authors.lastname: Freudenberg
authors.forename: Andrea
authors.initials: A
authors.lastname: Schwarzer
authors.forename: Sibylle
authors.initials: S
authors.lastname: Koletzko
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000737:chemistry*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D007410:Intestinal Diseases / Q000175:diagnosis; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis*; D008297:Male; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D039841:Leukocyte L1 Antigen Complex