Probiotics in irritable bowel syndrome - is the quest for the right strain over? Rapid review of existing guidelines and recommendations

Irritable bowel syndrome - controversies in diagnosis and management

INTRODUCTION

The irritable bowel syndrome (IBS) is the best-recognized disorder of gut brain interactions (DGBI). However, it is controversial if the Rome IV criteria iteration for IBS diagnosis is fit for purpose.

AREAS COVERED

This review critically evaluates Rome IV criteria for diagnosis of IBS and addresses clinical considerations in IBS treatment and management, including dietary factors, biomarkers, disease mimics, symptom severity, and subtypes. The role of diet in IBS is critically reviewed along with the influence of the microbiota, including small intestinal bacterial overgrowth.

EXPERT OPINION

Emerging data suggest the Rome IV criteria are more suitable for identifying severe IBS and least useful for sub-diagnostic patients who are still likely to benefit from IBS treatment. Despite convincing evidence that IBS symptoms are diet-driven and often postprandial, a relationship to eating is not a Rome IV diagnostic criterion. Few IBS biomarkers have been identified, suggesting the syndrome is too heterogeneous to be measured by a single marker, and combined biomarker, clinical, dietary, and microbial profiling may be needed for objective characterization. With many organic diseases mimicking and overlapping with IBS, it's important clinicians are knowledgable about this to mitigate the risk of missing comorbid organic intestinal disease and to optimally treat IBS symptoms.

A postbiotic fermented oat gruel may have a beneficial effect on the colonic mucosal barrier in patients with irritable bowel syndrome

Background

Impaired intestinal permeability and microbial dysbiosis are important pathophysiological mechanisms underlying irritable bowel syndrome (IBS). ReFerm^®, also called Profermin^®, is a postbiotic product of oat gruel fermented with Lactobacillus plantarum 299v. In this study, we investigated whether ReFerm^® has a beneficial effect on the intestinal epithelial barrier function in patients with IBS.

Materials and methods

Thirty patients with moderate to severe IBS-diarrhoea (IBS-D) or IBS-mixed (IBS-M) were treated with enema containing ReFerm^® or placebo. The patients underwent sigmoidoscopy with biopsies obtained from the distal colon at baseline and after 14 days of treatment with ReFerm^® or placebo twice daily. The biopsies were mounted in Ussing chambers, and paracellular and transcellular permeabilities were measured for 120 min. In addition, the effects of ReFerm^® or placebo on the epithelial barrier were investigated in vitro using Caco-2 cells.

Results

ReFerm^® reduced paracellular permeability (p < 0.05) and increased transepithelial resistance (TER) over time (p < 0.01), whereas the placebo had no significant effect in patients. In ReFerm^®-treated Caco-2 cells, paracellular and transcellular permeabilities were decreased compared to the control (p < 0.05) and placebo (p < 0.01). TER was increased in Caco-2 ReFerm^®-treated cells, and normalised TER was increased in ReFerm^®-treated Caco-2 cells compared to control (p < 0.05) and placebo-treated (p < 0.05) cells.

Conclusion

ReFerm^® significantly reduced paracellular permeability and improved TER in colonic biopsies collected from patients with IBS and in a Caco-2 cell model. Our results offer new insights into the potential benefits of ReFerm^® in IBS management. Further studies are needed to identify the molecular mechanisms underlying the barrier-protective properties of ReFerm^®.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [NCT05475314].

[Diverticular disease: treatment and management by general practitioners in Germany - high importance of probiotics in primary care]

INTRODUCTION

The symptomatic uncomplicated diverticular disease (SUDD) is often difficult to treat and guidelines only provide few evidence-based treatment options.

METHOD

For the German-wide survey, a questionnaire was sent to 13790 physicians. It contained questions concerning the status of medical care for patients with diverticula and queried their individual option in regards to current treatment options and challenges for the daily medical routine.

RESULTS

In total, 526 questionnaires were sent back for analysis. The biggest challenge for doctors handling patients with chronic diverticular disease (SUDD) is to make the correct diagnosis (17%) and the distinction to the irritable bowel syndrome (22%). Despite the high abundance of SUDD pathology, only 6% of the medical practitioners feel themselves sufficiently informed about it. The support for general practitioners by medical specialists (gastroenterologists) is limited: In the case of a SUDD or a diverticulitis diagnosis, the physicians sometimes receive an acute therapy plan (27%), but rarely get recommendations for diverticulitis pre- and post-care (11% and 18%), or assisting information for patient education (4%). For primary prophylaxis for persons with asymptomatic diverticula, practitioners give nutrition (41%) and life style (37%) recommendations, as well as probiotics (18%). After an acute diverticulitis, 42% recommend life style and nutrition modifications and 26% the intake of probiotics. For the treatment of SUDD symptoms, they advise mostly life style and nutrition modifications (45%) and probiotics (30%). About 60% of the doctors are satisfied with the efficacy of probiotics. Another 15% stated that they have not yet used them to treat SUDD. The main reasons for it seem to be the lack of reimbursability for probiotics (31%), the poor adherence of patients to therapy (20%) due to the slow onset of positive effects, and the difficulty of finding an evidence-based probiotic (16%).

CONCLUSION

In the daily medical routine the correct diagnosing of SUDD is a major challenge and supporting information by medical specialist is scarce. Physicians frequently choose life style and nutrition recommendations and the use of probiotics as treatment options. The majority of the general practitioners is thereby satisfied with the efficacy of probiotics for patients with chronic diverticular disease, even though the choice of an evidence-based probiotic is an obstacle.

A Combination of Xyloglucan, Pea Protein and Chia Seed Ameliorates Intestinal Barrier Integrity and Mucosa Functionality in a Rat Model of Constipation-Predominant Irritable Bowel Syndrome

Irritable Bowel Syndrome is a gastrointestinal disorder that affects the large intestine, which encompasses several symptoms including, but not limited to, abdominal pain, bloating and dysmotility. In particular, IBS associated with constipation (IBS-C) is characterized by hard and dry stools and inadequate evacuation and difficulty in defecation. Although several drugs ameliorate intestinal modifications and constipation-associated features, management of IBS is still a challenge. Natural compounds including Xyloglucan and pea protein (XP) and Chia seed powder (CS) are widely known to possess beneficial effects in counteracting several gastrointestinal disorders. Here, we aimed to assess the combined effects of XP and CS to treat constipation-related alterations in an IBS-C rat model. IBS-C was induced by gastric instillation of 2 mL of cold water (0-4 °C) for 14 days and Xiloglucan, Pea protein and Chia seeds (XP + CS) treatment was orally administered for 7 days. On day 22, colon tissues were collected for histological analysis. Our results showed that XP + CS administration attenuated constipation-related parameters by increasing body weight and food and water intake. Upon XP + CS treatment, from day 14 to 22, stool moisture content was restored to physiological level. Colonic tissues from IBS-C rats depicted a disruption of the organ architecture accompanied by edema. Loss of colonic structure was reflected by the marked reduction of tight junction protein expression, Occludin and zona occludens-1 (ZO-1). Administration of XP + CS treatment in IBS-C rats significantly ameliorated the colonic histological parameters and exerted a positive effect on barrier integrity by restoring the expression of Occludin and zona occludens-1 (ZO-1). Our findings demonstrated that the efficacy of XP and CS in managing constipation in rats is due to the ability of these compounds to form a protective barrier fortifying intestinal integrity and gut functionality.

Probiotics in the Management of Mental and Gastrointestinal Post-COVID Symptomes

Patients with “post-COVID” syndrome manifest with a variety of signs and symptoms that continue/develop after acute COVID-19. Among the most common are gastrointestinal (GI) and mental symptoms. The reason for symptom occurrence lies in the SARS-CoV-2 capability of binding to exact receptors, among other angiotensin converting enzyme 2 (ACE2) receptors in gastrointestinal lining and neuropilin-1 (NRP-1) in the nervous system, which leads to loss of gastrointestinal and blood-brain barriers integrity and function. The data are mounting that SARS-CoV-2 can trigger systemic inflammation and lead to disruption of gut-brain axis (GBA) and the development of disorders of gut brain interaction (DGBIs). Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are the most common DGBIs syndromes. On the other hand, emotional disorders have also been demonstrated as DGBIs. Currently, there are no official recommendations or recommended procedures for the use of probiotics in patients with COVID-19. However, it can be assumed that many doctors, pharmacists, and patients will want to use a probiotic in the treatment of this disease. In such cases, strains with documented activity should be used. There is a constant need to plan and conduct new trials on the role of probiotics and verify their clinical efficacy for counteracting the negative consequences of COVID-19 pandemic. Quality control is another important but often neglected aspect in trials utilizing probiotics in various clinical entities. It determines the safety and efficacy of probiotics, which is of utmost importance in patients with post-acute COVID-19 syndrome.