Diagnosis by Microbial Culture, Breath Tests and Urinary Excretion Tests, and Treatments of Small Intestinal Bacterial Overgrowth

A novel enzyme-based functional correlation algorithm for multi-omics reveals the potential mechanisms of traditional Chinese medicines: Taking Jian-Pi-Yi-Shen formula as an example

The integrated analysis of host metabolome and intestinal microbiome is an opportunity to explore the complex therapeutic mechanisms of traditional Chinese medicines. Currently, researchers mainly employ various statistical correlation analytical methods to investigate metabolome-microbiome correlations. However, these conventional correlation techniques often focus on statistical correlations and their biological meanings are always ignored, especially the functional relevance between them. Here, we developed a novel enzyme-based functional correlation (EBFC) algorithm to further improve the interpretability and the identified scope of microbe-metabolite correlations based on the conventional Spearman's analysis. The proposed EBFC algorithm is successfully utilized to reveal the therapeutic mechanisms of Jian-Pi-Yi-Shen (JPYS) formula on the treatment of adenine-induced chronic kidney disease (CKD) rats. JPYS, a TCM formula for treating CKD, has beneficial clinical effects. We tentatively revealed the potential mechanism of JPYS for treating CKD rats from the perspective of the serum metabolome, gut microbiome, and their interactions. Specifically, 11 metabolites and 19 bacterial genera in the CKD rats were significantly regulated to approaching normal status after JPYS treatment, suggesting that JPYS could ameliorate the pathological symptoms of CKD rats by reshaping the disturbed metabolome and gut microbiota. Further correlation analysis between the significantly perturbed metabolites, microbiota, and the related enzymes provided more strong evidence for the study of host metabolism-microbiota interactions and the therapeutic mechanism of JPYS on CKD rats. In conclusion, these findings will help us to deeply understand the pathogenesis of CKD and provide new insights into the therapeutic mechanism of JPYS.

Preventive and therapeutic effects of rifaximin on hepatic encephalopathy with differential application dosages and strategies: a network meta-analysis

BACKGROUND

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that affects the prognosis of patients with liver disease and is considered an independent risk factor for hospitalization and death. Rifaximin has been approved for HE treatment. This review will analyze the effect of rifaximin on different stages of HE with differential application dosages and strategies by traditional and network meta-analyses.

METHODS

We performed a systematic search of PubMed, EmBase, and Cochrane Library databases up to February 26, 2023, to identify randomized controlled trials (RCTs) about rifaximin for the prevention and treatment of HE. The outcomes included incidence of HE and HE progression, HE reversal, mortality, and adverse effects.

RESULTS

A total of 21 studies were included. In the primary prevention of HE, rifaximin significantly reduced the incidence of HE (OR: 0.66; 95% CI: 0.45, 0.96; p = 0.032). In secondary prevention, rifaximin significantly reduced the risk of recurrence in patients who were in remission (OR: 0.38; 95% CI: 0.28, 0.52; p < 0.001). In the treatment of minimal HE, rifaximin significantly reduced the breakthrough of MHE to OHE (OR: 0.17; 95% CI: 0.04,0.63; p = 0.008). Rifaximin also significantly improved the clinical symptoms of MHE and OHE patients (OR: 3.76; 95% CI: 2.69, 5.25; p < 0.001). However, rifaximin did not reduce mortality at any stage in HE patients (OR: 0.79; 95% CI: 0.58, 1.08; p = 0.133). Additionally, rifaximin did not increase the risk of adverse effects (OR: 0.96; 95% CI: 0.74, 1.24; p = 0.749). In the network meta-analysis, the 400 mg T.I.D. intervention had a relative advantage for HE risks in primary and secondary prevention. In the treatment of MHE, 600 mg b.i.d. was superior in preventing the breakthrough from MHE to OHE.

CONCLUSION

Rifaximin prevented HE risks and progression and improved clinical symptoms in patients with MHE but did not reduce mortality. For primary and secondary prevention, 400 mg t.i.d. could be considered. 600 mg b.i.d. could be considered in patients with MHE.

High Prevalence of Small Intestinal Bacterial Overgrowth Syndrome in ICU Patients: An Observational Study

Background: Small intestinal bacterial overgrowth (SIBO), although associated with potentially serious complications, has not been adequately studied in critically ill patients. The primary objective of this study was to assess the prevalence of SIBO in critically ill patients. Secondary outcomes included the assessment of its effect on ventilator-associated pneumonia (VAP), intensive care unit (ICU) length of stay (LOS), and all-cause in-hospital mortality rate. Methods: This prospective observational study was conducted in a mixed medical-surgical ICU. In 52 consecutive ICU patients, a noninvasive modified hydrogen breath test (HBT) with lactulose was employed for SIBO diagnosis. The HBT was conducted at predetermined time intervals (first day of admission; third, fifth, and seventh day of ICU stay). Patients with an abnormal HBT suggesting SIBO on the day of ICU admission were excluded from the study. Participants were classified as either positive or negative based on their HBT on the third, fifth, and/or seventh day. A comparative assessment of demographic data, APACHE II score, incidence of VAP, duration of ICU stay, and all-cause in-hospital mortality was conducted. Multivariate logistic regression analysis was performed to identify the predictive factors for SIBO. Results: The groups were homogeneous in terms of their baseline characteristics. The prevalence of SIBO was 36.5%. The all-cause in-hospital mortality was 34.6%. The presence of SIBO was associated with an increased incidence of VAP (P < .001) and a prolonged ICU length of stay (P < .033). All-cause in-hospital mortality was similar between the groups. Regarding the results of the multivariate logistic regression model, only age was identified as a statistically significant independent predictor of SIBO (OR 1.08, P = .018). Conclusions: The prevalence of SIBO in ICU patients appears to be increased. Both early diagnosis and effective treatment are of utmost importance, especially for critically ill patients since it appears to be associated with VAP and prolonged hospitalization.

Intestinal microbiome in short bowel syndrome: diagnostic and therapeutic opportunities

PURPOSE OF REVIEW

The intestinal microbiome plays a strong, complementary role in the development and integrity of the intestinal epithelium. This biology is crucial for intestinal adaptation, particularly after the mucosal insults that lead to short bowel syndrome (SBS). The purpose of this review is to discuss relationships between the intestinal microbiota and the physiology of intestinal adaptation.

RECENT FINDINGS

We will address interactions between the intestinal microbiome and nutritional metabolism, factors leading to dysbiosis in SBS, and common compositional differences of the gut microbiome in SBS patients as compared to healthy controls. We will also discuss novel opportunities to expand diagnostic and therapeutic interventions in this population, by using our knowledge of the microbiome to manipulate luminal bacteria and study their resultant metabolites. As microbial therapeutics advance across so many fields of medicine, this review is timely in its advocacy for ongoing research that focuses on the SBS population.Our review will discuss 4 key areas: 1) physiology of the intestinal microbiome in SBS, 2) clinical and therapeutic insults that lead to a state of dysbiosis, 3) currently available evidence on microbiome-based approaches to SBS management, and 4) opportunities and innovations to inspire future research.

SUMMARY

The clinical implications of this review are both current, and potential. Understanding how the microbiome impacts intestinal adaptation and host physiology may enhance our understanding of why we experience such clinical variability in SBS patients' outcomes. This review may also expand clinicians' understanding of what 'personalized medicine' can mean for this patient population, and how we may someday consider our nutritional, therapeutic, and prognostic recommendations based on our patients' host, and microbial physiology.

Small intestinal bacterial overgrowth: current update

PURPOSE OF REVIEW

This article aims to provide an up-to-date review of small intestinal bacterial overgrowth (SIBO), including etiology and risk factors, clinical manifestations, diagnostic evaluation for suspected SIBO, and therapeutic options.

RECENT FINDINGS

Recent advances in breath testing, capsule and urine-based testing have opened new avenues and improved diagnostic yield of SIBO. Nonantibiotic-based treatment strategies have shown promising results in initial trials.

SUMMARY

Small intestinal bacterial overgrowth (SIBO) is a condition defined by the excess bacteria or changes in bacterial composition of the small intestine. These are associated with various gastrointestinal (GI) symptoms such as bloating, abdominal distension, diarrhea, nutrient deficiencies, and even frank weight loss. Small bowel jejunal aspirate of >10 5 CFU/ml has traditionally been considered the gold standard for diagnosis. Glucose and lactulose breath testing have become more common in clinical practice as they are noninvasive, easily accessible, and have lower cost. Treatment focuses on the eradication of excess bacteria in the small bowel and is traditionally done with the use of oral antibiotics. Other emerging therapies may include probiotics, diet manipulation, and prokinetic agents.