Background: About 35% of humans have methane producing gut flora. Methane-producing IBS subjects were generally constipated. In animal models, methane infusion slows intestinal transit. Whether methanogenic flora alters colonic transit or stool characteristics and its relationship to constipation is unclear. Aim: To examine the prevalence and association of methanogenic flora in patients with slow transit constipation (ST) and normal transit constipation (NT) and non-constipated controls. Methods: Ninety six consecutive subjects with chronic constipation (Rome III) were evaluated with radio-opaque marker (ROM) transit studies and were classified as slow transit (>20% ROM retention) or normal transit. All constipated subjects and 106 non constipated controls underwent breath tests to assess methane production. Baseline CH4 of ≥ 3 ppm was used to define presence of methanogenic flora. Stool frequency and consistency were assessed using a prospective stool diary. Correlation analyses were performed. Results: Forty eight subjects had ST and 48 had NT. Prevalence of methanogenic flora was higher (p < 0.05) in ST (75%) compared to NT (44%) or controls (28%). ST patients had higher methane production compared to NT and controls (p<0.05). NT patients also produced more methane compared to controls (p < 0.05). There was moderate(p<0.05) correlation between baseline, peak and AUC of methane response with colonic transit but not with stool characteristics. Conclusions: Presence of methanogenic flora is associated with chronic constipation. Methane production following carbohydrate challenge and its prevalence were higher in ST than NT, although stool characteristics were similar in both groups. Methane production correlated with colonic transit, suggesting an association with stool transport but not with stool characteristics.

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SUMMARY BackgroundTreatment of chronic constipation remains challenging with 50% of patients dissatisfied with current therapy. There is an unmet need for natural and safe alternatives. Dried plums (prunes) have been used traditionally for constipation but their efficacy is not known.

Introduction Whether intestinal dysmotility and proton pump inhibitor (PPI) use either independently or together contributes to small intestinal bacterial overgrowth (SIBO), and/or small intestinal fungal overgrowth (SIFO) is not known. Aim Investigate the role of dysmotility and PPI use in patients with persistent gastrointestinal complaints. Methods Patients with unexplained gastrointestinal symptoms and negative endoscopy/radiology tests completed a validated symptom questionnaire and underwent 24-hour ambulatory antro-duodeno-jejunal manometry (ADJM). Simultaneously, duodenal aspirate was obtained for aerobic, anaerobic and fungal culture. Dysmotility was diagnosed by (> 2): absent phase III MMC, absent/diminished postprandial response, diminished amplitude of antral/intestinal phasic activity, impaired antro-duodenal coordination. Bacterial growth ≥103 CFU/mL or fungal growth was considered evidence for SIBO/SIFO. PPI use was documented. Correlation of symptoms with presence of SIBO or SIFO were assessed. Results 150 subjects (M/F=47/103) were evaluated; 94/150 (63%) had overgrowth: 38/94 (40%) had SIBO, 24/94 (26%) had SIFO, and 32/94 (34%) had mixed SIBO/SIFO. SIBO was predominately due to Streptococcus, Enterococcus, Klebsiella, and E. coli. SIFO was due to Candida. 80/150 (53%) patients had dysmotility and 65/150 (43%) used PPI. PPI use (p=.0063) and Dysmotility (p=.0003) were independent significant risk factors (p<0.05) for overgrowth, but together did not pose additional risk. Symptom profiles were similar between those with or without SIBO/SIFO. Conclusions Dysmotility and PPI use were independent risk factors for SIBO or SIFO and were present in over 50% of subjects with unexplained gastrointestinal symptoms. Diagnosis of overgrowth requires testing because symptoms were poor predictors of overgrowth.

Background-Fructose consumption is rising and its malabsorption causes common gastrointestinal symptoms. Because its absorption capacity is poorly understood, there is no standard method of assessing fructose absorption. We performed a dose response study of fructose absorption in healthy subjects in order to develop a breath test to distinguish normal from abnormal fructose absorption capacity.

The pathophysiology of persistent gastrointestinal (GI) symptoms in patients with diabetic gastroparesis is poorly understood. Our aim was to evaluate gastric sensation and accommodation to a meal in patients with diabetic gastroparesis and refractory symptoms. We performed intermittent, phasic balloon distensions of the stomach using a gastric barostat device in 18 patients with diabetes and gastroparesis unresponsive to prokinetic therapy and in 13 healthy volunteers. We assessed the biomechanical, sensory and accommodation responses of the stomach, during fasting and after liquid meal. During balloon distension, the sensory thresholds for discomfort were lower (P < 0.02) in patients with diabetes than those in controls, in both the fasting and the postprandial states. The accommodation response to a meal was significantly impaired (P = 0.01) in patients with diabetes when compared to controls, although fasting gastric tone was similar (P = 0.08). Patients with diabetic gastroparesis and refractory GI symptoms demonstrate sensori-motor dysfunction of the stomach, comprising either impaired accommodation, gastric hypersensitivity or both. An objective evaluation of these biomechanical and sensory properties may provide valuable mechanistic insights that could guide therapy.

WMC confirmed clinical suspicion, provided new diagnostic information, influenced clinical management, and detected many patients with generalized motility disorder. It had good device agreement with conventional tests.

OBJECTIVES There is limited and conflicting data regarding the role of esophageal hypersensitivity in the pathogenesis of functional chest pain (FCP). We examined esophageal sensori-motor properties, mechanics and symptoms in subjects with FCP. METHODS Esophageal balloon distension test (EBDT) was performed using impedance planimetry in 189 (m/f = 57/132) consecutive subjects with noncardiac, non-reflux chest pain, and 36 (m/f = 16/20) healthy controls. The biomechanical and sensory properties of subjects with and without esophageal hypersensitivity were compared to controls. The frequency, intensity and duration of chest pain were assessed. RESULTS: 143 (75 %) subjects had esophageal hypersensitivity and 46 (25%) had normal sensitivity. Typical chest pain was reproduced in 105/143 (74%) subjects. Subjects with hypersensitivity demonstrated larger cross-sectional area (CSA) (p<0.001), decreased esophageal wall strain (p<0.001) and distensibility (p<0.001), and lower thresholds for perception (p<0.01), discomfort (p<0.01) and pain (p<0.01) compared to those without hypersensitivity or healthy controls. Chest pain scores (mean ± SD) for frequency, intensity and duration were 2.5 ± 0.3, 2.2 ± 0.2 and 2.2 ± 0.2 respectively, and were similar between the two patient groups. CONCLUSIONS 75% of subjects with FCP demonstrate esophageal hypersensitivity. Visceral hyperalgesia and sensori-motor dysfunction of the esophagus play a key role in the pathogenesis of chest pain.