Predictors of clinical response to gluten-free diet in patients diagnosed with diarrhea-predominant irritable bowel syndrome

Clin Gastroenterol Hepatol. 2007 Jul;5(7):844-50; quiz 769. doi: 10.1016/j.cgh.2007.03.021. Epub 2007 Jun 5.

Abstract

Background & aims: Gluten sensitivity might cause abdominal symptoms in the absence of villous atrophy. We examined the prevalence of celiac disease-associated serum antibodies in diarrhea-dominant irritable bowel syndrome (d-IBS) patients and their efficacy in combination with HLA-DQ2 expression to predict the response to gluten-free diet.

Methods: HLA-DQA1*0501/DQB1*0201 expression and celiac disease-associated IgA and IgG serum antibodies against gliadin and tissue-transglutaminase were measured in 145 patients with d-IBS, 74 patients with untreated and treated celiac disease, and 57 patients with active IBD. Follow-up antibody levels, stool frequency, and gastrointestinal symptom scores were determined in 41 d-IBS patients (26 women, 15 men; median age, 46 years, range, 30-67 years) who participated in a nonrandomized evaluation of 6 months of gluten-free diet.

Results: Increased celiac disease-associated serum IgG, but not IgA, was found in the majority of patients with treated (55%) as in most patients with untreated celiac disease (97%). In d-IBS patients, celiac disease-associated serum IgG antibodies (37%) and HLA-DQ2 expression (39%) were more frequent than in IBD patients (18% and 23%, respectively). After 6 months of gluten-free diet, stool frequency and gastrointestinal symptom score returned to normal values in 60% of d-IBS patients who were positive and in 12% who were negative for HLA-DQ2 and celiac disease-associated serum IgG; both parameters combined yielded positive and negative predictive values of 56% (95% confidence interval, 30%-80%) and 88% (69%-97%), respectively.

Conclusions: Celiac disease-associated serum IgG and HLA-DQ2 expression can identify likely responders to gluten-free diet in d-IBS patients.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Anti-Idiotypic / immunology
  • Celiac Disease / complications
  • Celiac Disease / diet therapy
  • Celiac Disease / immunology
  • Diarrhea / diagnosis
  • Diarrhea / diet therapy*
  • Diarrhea / etiology
  • Diet, Protein-Restricted / methods*
  • Female
  • Follow-Up Studies
  • GTP-Binding Proteins
  • Gene Expression
  • Gliadin / immunology
  • Glutens / adverse effects*
  • HLA-DQ Antigens / genetics
  • HLA-DQ alpha-Chains
  • HLA-DQ beta-Chains
  • Humans
  • Immunoglobulin A / immunology
  • Immunoglobulin G / immunology
  • Irritable Bowel Syndrome / complications
  • Irritable Bowel Syndrome / diagnosis
  • Irritable Bowel Syndrome / diet therapy*
  • Male
  • Middle Aged
  • Prognosis
  • Retrospective Studies
  • Transglutaminases / immunology

Substances

  • Antibodies, Anti-Idiotypic
  • HLA-DQ Antigens
  • HLA-DQ alpha-Chains
  • HLA-DQ beta-Chains
  • HLA-DQA1 antigen
  • HLA-DQB1 antigen
  • Immunoglobulin A
  • Immunoglobulin G
  • Glutens
  • Gliadin
  • transglutaminase 2
  • Transglutaminases
  • GTP-Binding Proteins