High Prevalence of Pathological Hydrogen Breath Tests in Patients with Functional Dyspepsia

Digestion. 2019;100(3):186-191. doi: 10.1159/000494718. Epub 2018 Nov 14.


Background/aims: The aim of the study is to investigate the frequency of pathological hydrogen breath tests (HBT) in patients with clinical features of functional dyspepsia (FD) meeting the Rome criteria and normal testing of upper endoscopy and abdominal sonography.

Methods: We retrospectively included patients who underwent HBT (lactose, fructose, or glucose) between 2006 and 2012 and who had symptoms of FD. Patients were divided into 2 groups according to medical history and diagnostic results: (I) patients with suspected FD according to the Rome III criteria and (II) patients with an alternative diagnosis such as gastroesophageal reflux disease (GERD) or Crohn's disease (CD).

Results: A total of 207/404 patients were assigned to the FD group and 44.4% of these had at least 1 positive HBT and thus more frequently than patients with GERD (20.7%; n = 111; p < 0.001) and with CD (31.7%; n = 63; p = 0.07). Lactose and fructose HBT, but not glucose HBT, occurred significantly more frequently with pathological results than in patients with GERD (p = 0.02; p = 0.002). The probability of a positive HBT increased significantly with increasing number of performed HBT (p < 0.001).

Conclusion: We suggest that HBT should be considered in the clinical management of patients with suspected FD. In cases of positive HBTs, a potential causal therapy can be initiated.

Keywords: Fructose malabsorption; Functional dyspepsia; Hydrogen breath test; Lactose malabsorption; Small intestinal bacterial overgrowth.

MeSH terms

  • Administration, Oral
  • Adult
  • Breath Tests / methods
  • Crohn Disease / diagnosis
  • Diagnosis, Differential
  • Dyspepsia / diagnosis*
  • Feasibility Studies
  • Female
  • Fructose / administration & dosage
  • Gastroesophageal Reflux / diagnosis
  • Glucose / administration & dosage
  • Humans
  • Hydrogen / analysis*
  • Lactose / administration & dosage
  • Male
  • Middle Aged
  • Retrospective Studies


  • Fructose
  • Hydrogen
  • Glucose
  • Lactose