Noemi J. Baffy

Modulation of the gut microbiota: a focus on treatments for irritable bowel syndrome

ABSTRACT Irritable bowel syndrome (IBS), which is characterized by recurrent abdominal pain and disordered bowel habits, is one of the most common functional bowel disorders. IBS is a substantial burden on both patient health-related quality of life and healthcare costs. Several pathophysiologic mechanisms have been postulated for the occurrence of IBS, including altered gastrointestinal motility, visceral hypersensitivity, changes in gut permeability, immune activation, gut-brain dysregulation, central nervous system dysfunction, and changes in the gut microbiota. Of note, both qualitative and quantitative differences have been observed in the gut microbiota of a population with IBS versus a healthy population. Because of the substantial interest in the gut microbiota and its role as a therapeutic target in IBS, this article provides an overview of specific interventions with the potential to modulate the gut microbiota in IBS, including elimination diets, prebiotics, probiotics, synbiotics, and nonsystemic antibiotics. Although probiotics and synbiotics are generally well tolerated, differences in the composition and concentration of different bacterial species and inclusion or exclusion of prebiotic components varies widely across studies and has prevented strong recommendations on their use in IBS. For nonsystemic antibiotics, rifaximin is indicated in the United States for the treatment of IBS with diarrhea in adults and has been shown to be efficacious and well tolerated in well-designed clinical trials. Overall, more consistent evidence is needed regarding the efficacy and safety of elimination diets, prebiotics, probiotics, and synbiotics for the treatment of patients with IBS. Furthermore, additional well-designed studies are needed that examine alterations in the gut microbiota that occur with these interventions and their potential associations with clinical symptoms of IBS.

Irritable Bowel Syndrome and Female Patients

Irritable bowel syndrome is probably the most common functional gastrointestinal disorder and is characterized by abdominal pain along with altered bowel function. It is a disorder of female predominance. This article focuses on how being female influences the pathophysiology, diagnosis, management, and treatment of this common disorder and discusses the evidence and important controversies related to these areas.

International Normalized Ratio Does Not Predict Gastrointestinal Bleeding After Endoscopic Retrograde Cholangiopancreatography in Patients With Cirrhosis

Background Cirrhosis is often accompanied by an elevated international normalized ratio (INR) due to a decrease in pro-coagulant factors. An elevated INR in cirrhosis is often interpreted as an increased risk of bleeding. There are a paucity of data in the literature on the use of INR to predict risk of gastrointestinal bleeding (GIB) following endoscopic retrograde cholangiopancreatography (ERCP) in patients with cirrhosis. The aims of the study were to determine if there is a correlation between INR and GIB following ERCP in patients with cirrhosis, and to determine if there is a difference in frequency of post-ERCP complications in patients with and without cirrhosis. Methods A retrospective review of all ERCP procedures was performed at a tertiary care institution between 2012 and 2015. We identified ERCPs performed in patients with cirrhosis and compared them to a randomly selected group without liver cirrhosis. Univariate analysis was performed using Chi-square and ANOVA tests. A multivariable logistic regression model using generalized estimating equations was used to examine the association between INR and GIB. Results There were a total of 1,610 ERCPs performed from 2012 to 2015 with 129 performed in 56 patients with cirrhosis compared with 392 ERCPs performed in 310 patients without cirrhosis. There was no difference in the frequency of GIB following ERCP in both groups (P = 0.117). However, there was a difference in overall complications between both groups (P = 0.007), but no difference observed amongst Child-Turcotte-Pugh classes (P = NS). In a multivariable analysis, sphincterotomy during ERCP (odds ratio (OR) = 3.22; 95% confidence interval (CI): 1.05 - 9.94; P = 0.042) and cirrhosis (OR = 3.58; 95% CI: 1.22 - 10.47; P = 0.02) were significant for predicting GIB. Anti-coagulation (OR = 2.90; 95% CI: 0.82 - 10.23; P = 0.097) and INR were not significant in the multivariable model (OR = 2.09; 95% CI: 0.85 - 5.12; P = 0.10). Conclusion There was a statistical difference in overall complications between patients with and without cirrhosis but no difference was observed amongst Child-Turcotte-Pugh classes. Overall, INR was not a significant factor in predicting risk of bleeding in patients after ERCP.

Intractable Constipation in the Elderly

Opinion statementChronic constipation is a common gastrointestinal disorder disproportionately affecting the elderly. Immobility, polypharmacy, and physiologic changes contribute to its increased prevalence in this population. Unidentified and undertreated constipation leads to a significant negative impact on quality of life and an increase in healthcare spending. Careful physical examination and exploration of the clinical history can unmask primary and secondary forms of constipation, guiding diagnostic and therapeutic considerations. Non-pharmacologic treatment options include bowel training and biofeedback as well as the addition of fiber. Laxatives are safe and can be used long term; thus, they remain the mainstay of therapy. Newer agents with specific physiologic targets have proven to be effective in adults with chronic constipation, but data is lacking for safety profile in the elderly. Consideration for surgery in medically refractory cases should be entertained, while use of neuromodulation is not ready for prime time. This is a review of the currently available treatment options for chronic constipation in adults and specifically tailored towards the elderly.