title: Fecal assays detect hypersensitivity to cow's milk protein and gluten in adults with irritable bowel syndrome.
abstract: OBJECTIVE
  Some patients with irritable bowel syndrome (IBS)-like symptoms suffer from food hypersensitivity (FH); their symptoms improve when they are placed on elimination diets. No assays identify patients with FH with satisfactory levels of sensitivity. We determined the frequency of FH among patients with symptoms of IBS and the ability of fecal assays for tryptase, eosinophil cationic protein (ECP), or calprotectin to diagnose FH.
  
  
  METHODS
  The study included 160 patients with IBS, 40 patients with other gastrointestinal diseases, and 50 healthy individuals (controls). At the start of the study, patients completed a symptom severity questionnaire, fecal samples were assayed, and levels of specific immunoglobulin E were measured. Patients were observed for 4 weeks, placed on an elimination diet (without cow's milk and derivatives, wheat, egg, tomato, and chocolate) for 4 weeks, and kept a diet diary. Those who reported improvements after the elimination diet period were then diagnosed with FH, based on the results of a double-blind, placebo-controlled, oral food challenge (with cow's milk proteins and then with wheat proteins).
  
  
  RESULTS
  Forty of the patients with IBS (25%) were found to have FH. Levels of fecal ECP and tryptase were significantly higher among patients with IBS and FH than those without FH. The ECP assay was the most accurate assay for diagnosis of FH, showing 65% sensitivity and 91% specificity.
  
  
  CONCLUSIONS
  Twenty-five percent of patients with IBS have FH. These patients had increased levels of fecal ECP and tryptase, indicating that they might cause inflammation in patients with IBS. Fecal assays for ECP could be used to identify FH in patients with IBS.
authors.affiliation: Internal Medicine, Ospedali Civili Riuniti di Sciacca (AG), and University of Palermo, Palermo, Italy. acarroccio@hotmail.com
authors.forename: Antonio
authors.initials: A
authors.lastname: Carroccio
authors.forename: Ignazio
authors.initials: I
authors.lastname: Brusca
authors.forename: Pasquale
authors.initials: P
authors.lastname: Mansueto
authors.forename: Maurizio
authors.initials: M
authors.lastname: Soresi
authors.forename: Alberto
authors.initials: A
authors.lastname: D'Alcamo
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ambrosiano
authors.forename: Ilenia
authors.initials: I
authors.lastname: Pepe
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Iacono
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Lospalluti
authors.forename: Stella M
authors.initials: SM
authors.lastname: La Chiusa
authors.forename: Gaetana
authors.initials: G
authors.lastname: Di Fede
mesh_terms: D000293:Adolescent; D000328:Adult; D004032:Diet / Q000379:methods; D004311:Double-Blind Method; D047150:Eosinophil Cationic Protein / Q000032:analysis; D005243:Feces / Q000737:chemistry*; D005260:Female; D005983:Glutens / Q000276:immunology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications*; D039841:Leukocyte L1 Antigen Complex / Q000032:analysis; D008297:Male; D008875:Middle Aged; D016269:Milk Hypersensitivity / Q000175:diagnosis*; D010919:Placebos / Q000008:administration & dosage; D053802:Tryptases / Q000032:analysis; D021182:Wheat Hypersensitivity / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D039841:Leukocyte L1 Antigen Complex; D010919:Placebos; D005983:Glutens; D047150:Eosinophil Cationic Protein; C479220:RNASE3 protein, human; D053802:Tryptases