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.

Clinical features of constipation in general practice in Italy.

BACKGROUND: Definition and diagnosis of constipation remain challenging, partly due to different perceptions of the disease by doctors and patients. AIM: To evaluate prevalence and features of constipation among individuals seen in general practice, by comparing different diagnostic instruments. METHODS: Standardized questionnaires and the Bristol stool form scale were distributed to all subjects attending 10 general practitioners for any reason in a 2-week period. The questionnaires investigated constipation defined according to: (1) self-perception (yes/no); (2) a visual analogue scale; (3) Rome III Criteria. RESULTS: The prevalence of constipation in 1306 subjects (790 female, 516 male) resulted: (1) 34% self-reported; (2) 28% by visual analogue scale; (3) 24% by Rome Criteria. Constipation was more frequent in females. A high frequency of symptoms of obstructed defecations was observed with differences among patients with self-reported constipation with or without Bristol stool type 1-2. CONCLUSIONS: Prevalence of constipation among individuals attending their GP ranges between 24 and 34%, according to the different definitions adopted. Symptoms of obstructed defecations are frequent. The combination of self-evaluation and the Bristol stool type scale is potentially useful to identify subgroups of patients with different clinical features in general practice.