Are floating stools associated with specific functional bowel disorders?

Genesis of fecal floatation is causally linked to gut microbial colonization in mice

The origin of fecal floatation phenomenon remains poorly understood. Following our serendipitous discovery of differences in buoyancy of feces from germ-free and conventional mice, we characterized microbial and physical properties of feces from germ-free and gut-colonized (conventional and conventionalized) mice. The gut-colonization associated differences were assessed in feces using DNA, bacterial-PCR, scanning electron microscopy, FACS, thermogravimetry and pycnometry. Based on the differences in buoyancy of feces, we developed levô in fimo test (LIFT) to distinguish sinking feces (sinkers) of germ-free mice from floating feces (floaters) of gut-colonized mice. By simultaneous tracking of microbiota densities and gut colonization kinetics in fecal transplanted mice, we provide first direct evidence of causal relationship between gut microbial colonization and fecal floatation. Rare discordance in LIFT and microbiota density indicated that enrichment of gasogenic gut colonizers may be necessary for fecal floatation. Finally, fecal metagenomics analysis of 'floaters' from conventional and syngeneic fecal transplanted mice identified colonization of > 10 gasogenic bacterial species including highly prevalent B. ovatus, an anaerobic commensal bacteria linked with flatulence and intestinal bowel diseases. The findings reported here will improve our understanding of food microbial biotransformation and gut microbial regulators of fecal floatation in human health and disease.

Clinical, Physiological, and Psychological Correlates of the Improvement of Defecation during Menses in Women with Functional Gastrointestinal Disorders

BACKGROUND/AIMS

Little is known about the improvement in defecation frequently reported by women around menses. We aimed to describe clinical, physiological, and psychological correlates of this improvement in those with functional bowel disorders.

PATIENTS AND METHODS

We recruited 478 consecutive premenopausal adult females with no indication of gynecologic or psychiatric disease, who were attending an outpatient functional bowel disorders clinic. Patients completed a Rome III questionnaire, psychological evaluation stool form, and a 10-point Likert scale for constipation, diarrhea, bloating, and abdominal pain. These patients underwent physiological tests, anorectal manometry, and colonic transit time and were classified according to the presence or the absence of improvement in defecation during menses. The reverse selection procedure was used for model selection during multivariate logistic regression where statistically significant variables (p < 0.01) remained in the adjusted model.

RESULTS

Ninety-seven patients (20%) reported easier defecation during menstruation. These patients were younger (p < 0.001) but had similar body mass indices and psychological profiles as the other patients. Clinically, they only reported more frequent irritable bowel syndrome (IBS) with constipation (p = 0.007), with harder stools (p = 0.005) and delayed left colon transit time (p = 0.002). No anorectal manometric parameter was different between the 2 groups.

CONCLUSION

Improvement of constipation during menses is mainly associated with younger age and constipation-IBS phenotype and not with functional constipation.

Diarrhea after bariatric procedures: Diagnosis and therapy

Diarrhea after bariatric procedures, mainly those with malabsorptive elements including Roux-Y Gastric Bypass and Biliopancreatic Diversion, is common and an essential determinant of quality of life and micro- and macronutrient deficiencies. Bariatric surgery is the only sustainably successful method to address morbid obesity and its comorbidities, particularly gaining more and more importance in the specific treatment of diabetic patients. Approximately half a million procedures are annually performed around the world, with numbers expected to rise drastically in the near future. A multitude of factors exert their influence on bowel habits; preoperative comorbidities and procedure-related aspects are intertwined with postoperative nutritional habits. Diagnosis may be challenging owing to the characteristics of post-bariatric surgery anatomy with hindered accessibility of excluded segments of the small bowel and restriction at the gastric level. Conventional testing measures, if available, generally yield low accuracy and are usually not validated in this specific population. Limited trials of empiric treatment are a practical alternative and oftentimes an indispensable part of the diagnostic process. This review provides an overview of causes for chronic post-bariatric surgery diarrhea and details the particularities of its diagnosis and treatment in this specific patient population. Topics of current interest such as the impact of gut microbiota and the influence of bile acids on morbid obesity and especially their role in diarrhea are highlighted in order to provide a better understanding of the specific problems and chances of future treatment in post-bariatric surgery patients.