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.

New bismuth-containing quadruple therapy in patients infected with Helicobacter pylori: A first Italian experience in clinical practice.

BACKGROUND: Rising antibiotic resistance requires the evaluation of new and effective therapies. AIMS: To test the efficacy and safety of the new bismuth-containing quadruple therapy in patients infected with Helicobacter pylori. MATERIAL AND METHODS: Consecutive H. pylori-positive dyspeptic patients were enrolled, either naïve or with previous failure treatment. Patients were treated with Pylera® (three-in-one capsules containing bismuth subcitrate potassium 140 mg, metronidazole 125 mg, and tetracycline 125 mg) three capsules q.i.d. plus omeprazole 20 mg or esomeprazole 40 mg b.i.d. for 10 days. Eradication was confirmed using an urea breath test (at least 30 days after the end of treatment). Efficacy was assessed by UBT and safety by means of treatment-emergent adverse events. RESULTS: One hundred and thirty-one patients were included in the study: 42% of patients were naïve, and 58%, with previous failure treatment. H. pylori eradication was achieved in 124 patients (94.7%, 95% confidence intervals (CIs) 89.3-97.8) in ITT population. In the PP population, the percentage was 97.6% (95%, CIs 93.3-99.2). No difference in eradication rate was found either between naïve and previously treated patients (92.7% vs 96.0%, P=.383), or smoking and nonsmoking ones, or in patients taking omeprazole or esomeprazole. Treatment-emergent adverse events occurred in 35 patients (26.7%, 95% CIs 19.9-34.9). They were mild in all cases except in four, who discontinued the study due to diarrhea (three patients) and diffuse urticarial rush (one patient). CONCLUSIONS: Pylera® achieved a remarkable eradication rate in clinical practice, irrespective if it was used as first treatment or as a rescue therapy. Treatment-emergent adverse events were uncommon generally mild.