Current Gastroenterology Reports最新文献

Purpose of review: The prevalence of overweight and obesity has been increasing worldwide at an alarming rate. Gut microbiota intimately influence host energy metabolism, and immune response. Studies indicate a prominent role of gut dysbiosis in propagating inflammation that is associated with the development of obesity and obesity-related disorders such as type 2 diabetes mellitus, metabolic syndrome, and non-alcoholic fatty liver disease. This article will review the current literature on gut microbiome and its impact on obesity and obesity-related disorders.

Recent findings: An altered gut microbial composition in obesity and obesity-related disorders is associated with enhanced energy extraction from the non-digestible dietary carbohydrates, increased gut permeability, increased production of proinflammatory metabolites, such as lipopolysaccharides, resulting in systemic inflammation and insulin resistance. Gut microbiota modulation can be achieved either by dietary manipulation or by administration of probiotics, prebiotics, synbiotics, and/or fecal microbiota transplantation aiming at the improvement of the gut dysbiosis in obesity and metabolic disorders. Further clinical trials are required to better elucidate the dose, and frequency of these interventions and also their long-term impact on host metabolism.

Purpose of review: This review aims to analyze the evidence regarding the appropriateness of PEG placement in the following clinical situations: short bowel syndrome, head and neck cancer, dementia and palliative use in malignant bowel obstruction.

Recent findings: Percutaneous endoscopic gastrostomy (PEG) tubes are placed for a variety of clinical indications by numerous different specialties. First described in 1980, PEG tubes are now the dominant method of enteral access. Typically, PEG tubes are technically feasible procedures that can come with significant risk for both minor and major complications. Therefore, it is important to perform an in-depth, patient specific risk-benefit analysis when considering insertion. By analyzing the current evidence regarding benefits in these situations, superimposed by the lens of biomedical ethics, we make recommendations that are accessible to any provider who may be a consultant or proceduralist, helping to provide informed care that is in the patient's best interest.

Purpose of review: Epidemiologic studies and clinical trials have demonstrated the benefits of dietary fiber. This occurs through a combination of the physiochemical properties of fiber and through microbial fermentation that occurs in the colon which result in the production of short-chain fatty acids (SCFA). The purpose of this review is to highlight the physiochemical properties of fiber that result in the range of physiologic effects and to review the literature on the health benefits of acetate, propionate, and butyrate.

Recent findings: Of the variety of properties and functions exerted by dietary fibers, the fermentability and production of SCFA's are emphasized in this review. Studies done in both animal and humans reveal the anti-obesity, anti-inflammatory, and possible anti-neoplastic roles SCFAs exert at the mucosal level. Many clinical questions remain regarding the optimal dose, type, and method of delivery of fiber to exert the desired beneficial effects. It has the potential to be used in the management of clinical symptoms, prevention of disease, and improvement in human health. Further studies to address this novel use of fiber has the potential to make a large impact in clinical practice.

Purpose of review: Immune checkpoint inhibitor (ICI) therapy revolutionized the treatment of multiple solid and hematologic malignancies. Yet, with it came profound inflammatory toxicities that mimic autoimmune diseases, termed immune-related adverse events (irAEs). Prominent among these is gastrointestinal inflammation, including a spectrum of gastritis, enteritis, and colitis. Here we synthesize an approach to immune checkpoint related enterocolitis (irEC) - including diagnostics and therapeutics - underpinned by new insights into the mechanism behind these phenomena.

Recent findings: This review presents updated insights on how to approach irEC, including novel approaches to selective immunosuppressive therapy, the role of fecal microbiota transplant, and the underlying cellular mechanisms of irEC. This review provides an update on irEC diagnosis and therapy, with considerations of new therapies and special patient populations. The field of gastrointestinal irAEs requires additional investigation, which will ultimately provide the tools required for patients to continue to receive life-saving ICI therapy.

Purpose of review: To outline the development, rationale, and practical use of therapeutic drug monitoring in patients with inflammatory bowel disease.

Recent findings: Therapeutic drug monitoring is traditionally discussed in terms of a proactive or reactive approach. However, these terms are not always consistently defined and can be confusing when translating research to clinical practice. Personalized approaches incorporating clinical context and precision medicine are emerging. Personalized therapeutic drug monitoring combines a structured and proactive strategy for monitoring biologic concentrations as well as identification of antidrug antibody development or subtherapeutic dosing in the setting of loss of response. Optimizing biologic therapy can improve outcomes and avoid loss of response. Why, when, and how we measure drug troughs and anti-drug antibodies is a moving target, though what is known is that the appropriate and evidence-based use of this practice prevents adverse events and improves outcomes in patients with inflammatory bowel disease.

Purpose of review: Ulcerative colitis (UC) is a chronic disease with an increasing incidence. Recent guidelines emphasize treating toward objective targets, requiring the use of effective, steroid-sparing therapies. This review summarizes the safety and efficacy data of available therapies as well comparative effectiveness studies in order to help the reader make rational treatment decisions.

Recent findings: Following the approval of tumor necrosis factor alpha antagonists, we have seen recent regulatory approval of several additional biologic and small molecule agents from several therapeutic classes (integrin antagonists, interleukin 12/23 antagonists, Janus kinase inhibitors, and sphingosine-1-phosphate receptor antagonists) for UC. Randomized, controlled trials, real-world analyses, and network meta-analyses have investigated the comparative safety and efficacy of these therapies in order to help clinicians better position these therapies in clinical practice. Numerous agents are now approved for the treatment of UC. This evidence-based review will help the reader understand the important factors weighing into treatment decisions for patients with UC and enable patient education and discussion with a focus on a shared decision-making approach.

Purpose of review: Children with aerodigestive disorders frequently have concerns regarding difficulty breathing, swallowing, and growing. In this review, we explored the role of pediatric gastroenterologists in the evaluation of complex aerodigestive disorders and the overall approach to these often-challenging patients.

Recent findings: Pediatric gastroenterologists evaluate children with aerodigestive concerns ranging from dysphagia and gastroesophageal reflux to complex congenital abnormalities such as esophageal atresia. Diagnostic tools, such as multichannel intraluminal impedance-pH monitoring, are used for diagnosing gastroesophageal reflux and assessing the correlation with symptoms. Endoscopic evaluation, and in some complex cases, with therapeutic dilations may also be performed. Gastrointestinal dysmotility evaluation with manometry studies are also being increasingly utilized. Multidisciplinary aerodigestive programs can provide a coordinated approach to children with complex airway, pulmonary and gastrointestinal tract disorders. A pediatric gastroenterologist's expertise and specialized skills not only offer many diagnostic tools for these complicated medical cases but are also important in long term medical management.

Purpose of review: Diet and nutrition have emerged as key factors in the development and course of inflammatory bowel disease (IBD), including the approach to therapy. We present an overview of evidence-based recommendations and recent research in dietary therapy and nutrition management for patients with IBD.

Recent findings: Patients with IBD should undergo a comprehensive nutrition assessment with the assistance of a registered dietitian (RD), including screening for micronutrient deficiencies. Multiple specialized whole foods and liquid formula diets have been evaluated as part of induction and maintenance therapy for IBD. Nutritional status should ideally be optimized in the perioperative setting as well. Nutritional issues are prevalent among IBD patients and should be addressed by a multidisciplinary team, tailored to each patient's disease type, severity and course, including response to medical therapy and need for surgical management, as well as relevant psychosocial considerations.

Purpose of review: As the incidence of inflammatory bowel disease (IBD) rises, gastroenterologists are more commonly facing management of the disease in women of childbearing age. This coincides with the development of new IBD therapies whose use in pregnancy must be considered.

Recent findings: This review provides updated recommendations for newer biologic agents and small molecules that have been approved for IBD treatment since the previous guidelines were published. In addition, recent research has found that prior IBD-related surgeries, not just ileal pouch-anal anastomosis, can impact pregnancy outcomes. Reassuringly, assisted reproductive technology for IBD patients has been found to have similar success rates to the non-IBD population. Ensuring disease remission prior to conception and throughout pregnancy is key for optimizing pregnancy and fetal outcomes. As gastroenterologists play an integral role in the management of IBD throughout the peripartum period, this review summarizes recent studies in combination with existing guidelines to address preconception counseling, medication safety, and management for quiescent and active disease throughout pregnancy.

Purpose of review: The gastrocolonic response (GCR), is a physiologic increase in motor activity of the colon, which usually occurs within minutes following meal ingestion. Over the years several triggers that provoke GCR were recognized including gastric dilation, caloric intake, and fat component of the meal. The response is mediated by the vagal nerve and neurohumoral mechanisms, and it can be modified by several pharmacological factors. Assessment of GCR is part of high-resolution colonic manometry studies, performed in patients with suspected colonic dysmotility. This review highlights the physiologic basis of GCR as well as its clinical and diagnostic features and implementation in variable pathological conditions and clinical practice.

Recent findings: GCR has a role in patients with constipation, diabetes, dumping syndrome, bowel hyper and hypomotility and irritable bowel syndrome. Novel sensory triggers for GCR were recently recognized. GCR is a physiological response which is evaluated during colonic manometry studies. Abnormal GCR is a marker of an underlying pathology, which can provide a potential target for treatment.