Helicobacter pylori infection and small intestinal bacterial overgrowth
Introduction: H. pylori is a remarkable bacterium, because it has one of the highest urease activities of all known bacteria. Since H. pylori infection may increase the intra-gastric pH due to the production of ammonia, this bacterium may be a causative agent of small intestinal bacterial overgrowth (SIBO). The purpose of the present study was to investigate the presence of small intestinal bacterial overgrowth (SIBO) in patients with active H. pylori infection assessed by functional breath testing.
Patients and Methods: All in all 109 patients with gastrointestinal complaints, who were referred for the H. pylori 13C-urea breath test (13C-UBT) by general practitioners and specialists, were also tested for the presence of SIBO by the glucose hydrogen (H2)/methane (CH4) breath test (HMBT). The Fisher's exact test was performed to compare 13C-UBT with glucose H2/CH4 breath test results. A detailed anamnesis was carried out about the history of H.-pylori infection, eradication therapies, proton pump inhibitor (PPI)-intake and co-morbidities.
Results: In total, 36/109 (33.0%) patients had a positive H. pylori 13C-UBT, and 35/109 (32.1%) patients had a positive glucose HMBT. Interestingly, 19/36 (52.8%) individuals with a positive 13C-UBT also had a positive glucose HMBT, whereas only 16/73 (21.9%) patients with a negative 13C-UBT showed a positive glucose HMBT (p = 0.002), respectively. Overall 13/38 (34.2%), 4/12 (33.3%), 1/2 (50.0%), and 1/2 (50.0%) patients, who had completed one, two, three and four eradication therapies, were diagnosed with SIBO by HMBT, respectively.
Conclusions: In the present study active H. pylori infection was found significantly associated with the presence of SIBO as determined by functional breath testing. In addition SIBO rates appeared to have increased after completed eradication therapies. However, further longitudinal studies are warranted, to fully elucidate the relationship and treatment modalities of coincident H. pylori infection and SIBO.