Assessment of small intestinal bacterial overgrowth and methane production in patients on chronic proton-pump inhibitor treatment: prevalence and role of rifaximin in its management in primary care.

BACKGROUND: Although proton pump inhibitor (PPI) drugs have considered able to induce small intestinal bacterial overgrowth (SIBO), no data are so far available from primary care (PC). We assessed the prevalence of SIBO and methane (CH4) production consequent to chronic PPI therapy using Lactulose Breath Test (LBT). Secondary aim was to explore the possible role of rifaximin in treating PPI-induced SIBO patients. METHODS: One hundred twenty-five gastroesophageal reflux disease patients, constantly treated with PPI for at least 6 months and undergoing to LBT, were retrospectively assessed. An age-matched control population (control) of 100 patients, which had not used PPI in the last 6 months, was also enrolled. In the PPI group, SIBO positive patients and CH4 producers were treated with rifaximin 1200 mg/daily for 14 days and re-checked with LBT one month after the end of treatment. The area under the curve (AUC) before and after treatment was also calculated for both SIBO positive patients and CH4 producers. RESULTS: In the PPI group, SIBO prevalence was significantly higher vs. controls (38/125 [30.4%] vs. 27/100 [27%], P<0.05). 77/125 (61.6%) PPI patients were found to be CH4 producers vs. 21/100 (21%) controls (P<0.05). Among SIBO patients in the PPI group, 34 (89.4%) were also CH4 producers vs. 17/27 (63%) controls (P<0.05). After treatment, LBT resulted negative in 15/22 SIBO patients (68.1%) (P<0.05) and in 18/34 CH4 producers (52.9%) (P<0.05). At the AUC analysis, an overall reduction of 54.2% for H2 in SIBO patients and of 47.7% for CH4 was assessed after rifaximin treatment (P<0.05). CONCLUSIONS: Our data showed that chronic use of PPI could be able to increase the prevalence of SIBO and to shift the intestinal microbial composition towards a CH4-producing flora. rifaximin could represent a useful therapeutical option for PPI-induced SIBO and for modulating CH4-producing flora.

Appropriateness in prescribing PPIs: A position paper of the Italian Society of Gastroenterology (SIGE) - Study section "Digestive Diseases in Primary Care".

The introduction of proton pump inhibitors (PPIs) into clinical practice about thirty years ago has greatly improved our therapeutic approach to acid-related diseases for their well-recognized efficacy and safety. Despite the well-defined indications, however, the use of PPIs continues to grow every year in both western and eastern countries and this phenomenon poses serious queries that include the onset of potential adverse effects and the increase in health care costs. The major reason explaining this worrying market expansion is the inappropriate use of PPIs. In order to re-establish a correct use of these effective drugs in daily clinical practice, the Italian Society of Gastroenterology (SIGE), nominated a panel of experts who reviewed the available clinical literature and produced a series of updated position statements on the use of PPIs in clinical practice.