A Study on Chronic Proton Pump Inhibitor Usage and Small Intestinal Bacterial Overgrowth (SIBO)

Introduction: Small Intestinal Bacterial Overgrowth (SIBO) has a wide clinical spectrum, and may be associated with both maldigestion and malabsorption. Proton Pump Inhibitors (PPI) are one of the most widely prescribed medications in view of their safety profile. This has lead to their indiscriminate usage, giving rise to growing concerns of SIBO in the setting of long term PPI usage. Aim: To evaluate the correlation between chronic PPI usage (>2 months) and SIBO, as diagnosed by duodenal aspirate cultures. Materials and Methods: A total of 80 subjects were included in this prospective observational study. All patients were subjected to Upper Gastrointestinal Endoscopy (UGIE) and one mL duodenal aspirate was collected for bacterial cultures. A growth of more than 10(5) CFU/mL was considered positive for SIBO. The inter-group statistical comparison was done using Chisquare test, and a p-value of <0.05 was taken as significant. Results: The mean age of the entire study group was 45.4 years. Gender wise, 72.5% of the patients were males. Gastritis, as detected by endoscopy was seen in 37.5% patients, and 35% patients had infection with H.pylori. The use of NSAIDS was noted amongst 36% of the study population. The most common PPI used was Pantoprazole and majority of the patients had used it for greater than six months. Flatulence was the predominant symptom of SIBO in 41% study subjects. On UGIE, 34 out of 80 (42.5%) patients had abnormal findings and 19 out of 80 (23.8%) patients had SIBO as per positive duodenal aspirate culture reports (>10(5) CFU per mL). Based on various intergroup analysis, SIBO was not significantly (p>0.05), associated with any form of PPI usage, H.pylori infection, NSAID use or smoking/alcohol abuse. Conclusion: It was observed in this single center study that, SIBO was not associated with duration/ dose/type of PPI usage. This study needs further validation with a case-control design in a diverse patient population.