Management of irritable bowel syndrome with diarrhea: focus on eluxadoline

Differential Diagnosis of Chronic Diarrhea: An Algorithm to Distinguish Irritable Bowel Syndrome With Diarrhea From Other Organic Gastrointestinal Diseases, With Special Focus on Exocrine Pancreatic Insufficiency

Chronic diarrhea, defined as diarrhea persisting for more than 4 weeks, affects up to 5% of the population regardless of patient age, sex, race, or socioeconomic status. The impact on patient health and quality of life is substantial, and diagnosis and management of these patients have significant economic consequences for health care services. The differential diagnosis of chronic diarrhea is broad, with etiologies including infections, endocrinopathies, maldigestive/malabsorptive conditions, and disorders of gut-brain interaction. The considerable overlap of symptoms across this spectrum makes accurate diagnosis problematic and may lead to delays in diagnosis or misdiagnosis. In this narrative review, we consider the differential diagnosis of chronic diarrhea, focusing on irritable bowel syndrome with diarrhea and exocrine pancreatic insufficiency, two conditions that may present similarly but have very different underlying causes and require significantly different management strategies. We outline a 4-step diagnostic strategy and propose a straightforward algorithm to assist in efficiently differentiating irritable bowel syndrome from exocrine pancreatic insufficiency and other causes of chronic diarrhea. We anticipate that these aids will improve diagnostic accuracy, which ultimately should lead to improvements in patients' health-related quality of life and reduce the societal burden on health care services.

Functional Gastrointestinal Disorders with Psychiatric Symptoms: Involvement of the Microbiome-Gut-Brain Axis in the Pathophysiology and Case Management

Functional Gastrointestinal Disorders have been an important cause of poor life quality in affected populations. The unclear etiology and pathophysiological mechanism alter the clinical evolution of the patient. Although a strong connection with psychological stress has been observed, it was not until recently that the gut-brain axis involvement has been revealed. Furthermore, the current literature not only promotes the gut-brain axis modulation as a therapeutical target for functional digestive disorders but also states that the gut microbiome has a main role in this bi-directional mechanism. Psychiatric symptoms are currently recognized as an equally important aspect of the clinical manifestation and modulation of both the digestive and central nervous systems and could be the best approach in restoring the balance. As such, this article proposes a detailed description of the physiology of the microbiome-gut-brain axis, the pathophysiology of the functional gastrointestinal disorders with psychiatric symptoms and current perspectives for therapeutical management, as revealed by the latest studies in the scientific literature.

Acupuncture vs. antispasmodics in the treatment of irritable bowel syndrome: An adjusted indirect treatment comparison meta-analysis

Background: Acupuncture has been extensively applied to manage irritable bowel syndrome (IBS) in clinical practice in China. Some randomized controlled trials (RCTs) have demonstrated their efficacy, but it has rarely been compared with first-line antispasmodics to verify their effectiveness. Therefore, we compare acupuncture with antispasmodics in the treatment of IBS by using an adjusted indirect treatment comparison meta-analysis.

Methods: Embase, OVID Medline, and the Cochrane Central Register of Controlled Trials databases were searched from inception to 14 March 2022, with no language restrictions. RCTs comparing antispasmodics or acupuncture with placebo or one of the antispasmodics were enrolled. The primary outcome of interest was the improvement of abdominal pain. And the secondary outcomes of interest were the relief of global IBS symptoms and adverse events. The random-effects model was utilized to pool data. The effect size was measured by standardized mean difference (SMD) or relative ratio, and the effectiveness of acupuncture and different antispasmodics were ranked by P-scores.

Results: Thirty-five RCTs (n = 5,190) were included. The analysis showed that cimetropium, drotaverine, acupuncture, and pinarverium were superior over placebo in relieving abdominal pain; cimetropium (SMD, −3.00 [95%CI, −4.47 to −1.53], P-score = 0.99) ranked the most effective. In pairwise comparisons, acupuncture had a greater improvement than most antispasmodics except cimetropium and drotaverine in relieving abdominal pain, although the between-group difference was statistically insignificant. In the analysis of continuous outcome in the relief of global IBS symptoms, the result showed that pinaverium was more effective (SMD, 1.72 [95%CI, 0.53 to 2.92], P-score = 0.90) than placebo. Trimebutine and acupuncture had greater improvements than placebo, but no significant difference was shown between groups. In pairwise comparisons, acupuncture was more effective than pinaverium (SMD, −1.11 [95%CI, −1.94 to −0.28]) in relieving global IBS symptoms. In the analysis of adverse events, acupuncture had a lower adverse event rate than most of the other antispasmodics.

Conclusion: Cimetropium, drotaverine, and acupuncture were all better than placebo in improving abdominal pain. Acupuncture was preferred over pinaverium in relieving global IBS symptoms, and acupuncture had lower adverse events than most antispasmodics.

Antispasmodic Effect of Bergamot Essential Oil on Rat Isolated Gut Tissues

Preclinical data indicate that bergamot essential oil (BEO) can modulate the synaptic functions within the central nervous system (CNS). Particularly, several data shows that essential oil is endowed with reproducible analgesic and anxiolytic effects that may derived from the ability to modulate the excitatory and inhibitory neurotransmission in the CNS. Although there are differences in the functional complexity of the enteric nervous system (ENS), it is likely that the phytocomplex has biological properties in gut superimposable to those showed in the CNS. Accordingly, the aim of this study was to investigate ex-vivo the effect of bergamot essential oil and its main constituents on the contractile activity of rat isolated colon, jejunum and ileum induced by different muscle stimulants such as acetylcholine (10⁻⁶ M) and potassium chloride (80 mM). Our present data demonstrate that BEO inhibits cholinergically- and non cholinergically-mediated contractions in rat isolated gut and that linalool is the most active component. These results suggest that the phytocomplex might be useful in the treatment of spastic disorders in ENS mainly characterized by the presence of pain; incidentally, irritable bowel syndrome (IBS) is a painful condition in which a role for neurotransmitter dysfunction has been envisaged. More investigation is required for clinical translation of the present data.

Aloe barbadensis Mill. extract improves symptoms in IBS patients with diarrhoea: post hoc analysis of two randomized double-blind controlled studies

BACKGROUND

Aloe barbadensis Mill. (Aloe) extract was found to be well-tolerated, safe and showed beneficial effects in subsets of irritable bowel syndrome (IBS) patients in two randomized, double-blind, controlled studies. However, the individual studies were underpowered to perform subgroup analyses. We therefore determined the effect of Aloe extract in IBS subgroups in a post hoc analysis combining the results from the two studies.

METHODS

Data from the two controlled studies comparing Aloe and control treatment taken orally for 4 weeks, were pooled. Both studies included IBS patients fulfilling the ROME III criteria and IBS Symptom Severity Score (IBS-SSS) was assessed. We analysed the effect of Aloe extract on IBS symptom severity and the proportion of responders (IBS-SSS reduction ⩾ 50) in IBS subgroups.

RESULTS

In total, 213 IBS patients were included in the post hoc subgroup analyses. A reduction in overall symptom severity, primarily driven by effect on pain severity and frequency, comparing baseline versus end of treatment, was recorded in IBS patients with diarrhoea (IBS-D) receiving Aloe (n = 38, p < 0.001) but not control treatment (n = 33, p = 0.33), with difference between the treatment groups (p = 0.01). Moreover, the frequency of responders was higher in IBS-D patients receiving Aloe (n = 22, 58%) compared to control treatment (n = 10, 30%) (p = 0.02). The effect of Aloe extract treatment on IBS symptom severity was not superior to control treatment in the other IBS subtypes.

CONCLUSION

Aloe extract improves symptom severity in IBS-D patients and can be regarded as a safe and effective treatment option for this patient group.