Intestinal Bacterial Overgrowth Research Articles

The Gut Microbiota in Parkinson Disease: Interactions with Drugs and Potential for Therapeutic Applications.

The concept of a 'microbiota-gut-brain axis' has recently emerged as an important player in the pathophysiology of Parkinson disease (PD), not least because of the reciprocal interaction between gut bacteria and medications. The gut microbiota can influence levodopa kinetics, and conversely, drugs administered for PD can influence gut microbiota composition. Through a two-step enzymatic pathway, gut microbes can decarboxylate levodopa to dopamine in the small intestine and then dehydroxylate it to m-tyramine, thus reducing availability. Inhibition of bacterial decarboxylation pathways could therefore represent a strategy to increase levodopa absorption. Other bacterial perturbations common in PD, such as small intestinal bacterial overgrowth and Helicobacter pylori infection, can also modulate levodopa metabolism, and eradication therapies may improve levodopa absorption. Interventions targeting the gut microbiota offer a novel opportunity to manage disabling motor complications and dopa-unresponsive symptoms. Mediterranean diet-induced changes in gut microbiota composition might improve a range of non-motor symptoms. Prebiotics can increase levels of short-chain fatty acid-producing bacteria and decrease pro-inflammatory species, with positive effects on clinical symptoms and levodopa kinetics. Different formulations of probiotics showed beneficial outcomes on constipation, with some of them improving dopamine levels; however, the most effective dosage and duration and long-term effects of these treatments remain unknown. Data from faecal microbiota transplantation studies are preliminary, but show encouraging trends towards improvement in both motor and non-motor outcomes.This article summarises the most up-to-date knowledge in pharmacomicrobiomics in PD, and discusses how the manipulation of gut microbiota represents a potential new therapeutic avenue for PD.

Development of Innovational Brem Bali Products with Probiotics through Immobilization of Durian Skin Flour as a Healthy Alcoholic Beverage

The alcohol produced from the fermentation process in the traditional Balinese brem drink is one of the obstacles. Innovation and functional studies of brem Bali products are needed to be standardized and industrialized. The Bali brem fermentation process uses a dry starter, yeast, and a dominant growing microbe, Saccharomyces cerevisiae. The alcohol content in Bali brem ranges from 3-10%. Several studies have studied the probiotics in alcoholic beverages to provide health benefits potentially. In addition, durian skin flour is claimed to be used as a probiotic immobilizer. The development of brem drink with the addition of probiotics can have a major impact on health; in addition to the benefits of brem as a fermented drink, it also provides probiotic effects for health, including helping digestion as irritable bowel syndrome, reducing digestive tract symptoms (constipation, non-pathogenic diarrhoea, and flatulence), intolerance lactose, as the body’s defence (allergies such as eczema, atopic), cariogenic, carcinogenic, mutagenic, tumours, intestinal inflammation, intestinal bacterial overgrowth, lowering blood cholesterol, and hypertension.

Study of fatty acid-binding protein and Bacteroidetes and Firmicutes levels in patients with metabolic-associated fatty liver disease in combination with type 2 diabetes mellitus and small intestinal bacterial overgrowth syndrome

The aim of the study was to examine serum levels of liver and intestinal fatty acid-binding proteins (L-FABP and I-FABP), fecal numbers of Bacteroidetes (B) and Firmicutes (F) in patients with metabolic-associated fatty liver disease (MAFLD) in combination with type 2 diabetes mellitus (Т2DM) and small intestinal bacterial overgrowth (SIBO) syndrome. Materials and methods. The prospective, interventional, randomized study included 51 patients with MAFLD in combination with Т2DM, who were examined and divided into 2 groups. Group 1 consisted of 24 patients with MAFLD and Т2DM without SIBO. Group 2 was comprised of 27 patients with MAFLD in combination with Т2DM and SIBO. The control group included 20 apparently healthy individuals. Serum levels of L-FABP and I-FABP were measured by ELISA method using the Human L-FABP and I-FABP ELISA Kit test systems, respectively (Elabscience, USA). Fecal numbers of B and F were determined by real-time PCR. Bacterial DNA was detected in a thermal cycler Rotor-Gene 6000 (QIAGEN, Germany) using DNA 16S rRNA primers and NanoDrop ND-8000 reagents (Thermo Scientific, USA). Results. To assess the state of intestinal permeability, serum levels of L-FABP and I-FABP were examined and numbers of phylum F and В as well as their ratio were calculated. Patients of both groups have been found to have increased serum levels of L-FABP, I-FABP, numbers of B in fecal samples and decreased numbers of F and F/B ratio. Conclusions. The study results obtained have revealed increased intestinal permeability and demonstrated an important diagnostic value of serum L-FABP and I-FABP as a biomarker of intestinal permeability in diabetic MAFLD patients with or without SIBO. Increased fecal numbers of Bacteroidetes, decreased numbers of Firmicutes and F/B ratio have been detected in diabetic MAFLD patients with or without SIBO.

Small Intestine Bacterial Overgrowth is associated with increased Campylobacter and epithelial injury in duodenal biopsies of Bangladeshi children.

Small intestine bacterial overgrowth (SIBO) has been associated with enteric inflammation, linear growth stunting, and neurodevelopmental delays in children from low-income countries. Little is known about the histologic changes or epithelial adherent microbiota associated with SIBO. We sought to describe these relationships in a cohort of impoverished Bangladeshi children. Undernourished 12-18-month-old children underwent both glucose hydrogen breath testing for SIBO and duodenoscopy with biopsy. Biopsy samples were subject to both histological scoring and 16s rRNA sequencing. 118 children were enrolled with 16s sequencing data available on 53. Of 11 histological features, we found that SIBO was associated with one, enterocyte injury in the second part of the duodenum (R = 0.21, p = 0.02). SIBO was also associated with a significant increase in Campylobacter by 16s rRNA analysis (Log 2-fold change of 4.43; adjusted p = 1.9 x 10-6). These findings support the growing body of literature showing an association between SIBO and enteric inflammation and enterocyte injury and further delineate the subgroup of children with environmental enteric dysfunction who have SIBO. Further, they show a novel association between SIBO and Campylobacter. Mechanistic work is needed to understand the relationship between SIBO, enterocyte injury, and Campylobacter.

The role of intestinal microbiota in the development of dysfunction of the biliary system in children

Objective: to study the state of the intestinal and biliary microbiota in children with intestinal and gallbladder dysfunction and to determine the features of the component composition of the biliary microbiota. Methods: We examined 20 children with irritable bowel syndrome (IBS). The presence of small intestinal bacterial overgrowth (SIBO) syndrome was determined (using a hydrogen breath test with lactulose), microbial markers of the intestinal and biliary microbiota (using gas chromatography-mass spectrometry). We also performed microscopy of bile (phase-contrast light microscopy) obtained through duodenal intubation. Results: In all children with IBS, SIBO was verified in the small intestine, with insufficiency of the ileocecal valve in half of them, associated with hypomotor dyskinesia of the gallbladder. Microscopy of the bile revealed a large number of crystals and leukocytes. A study of microbial markers of intestinal and biliary microbiota in all children with IBS and SIBO revealed excessive bacterial associative growth of gram-negative opportunistic bacteria in combination with viruses of the Herpes family. An increase in the level of lipopolysaccharides (2 times higher than normal) and a deficiency of microbial markers of the main groups of microorganisms (anaerobic bacteria) responsible for metabolization processes in the enterohepatic circulation (plasmalogen less than 50 μg/ml) were recorded. Excessive growth of 28 species of opportunistic bacteria was detected in bile in diagnostically significant concentrations associated with hypomotor dysfunction of the gallbladder and lithogenicity of bile. Conclusion: A violation of the biliary microbiota was established with an increase in the proportion of gram-negative opportunistic bacteria, the spectrum of which was close to that of the intestine and their association with intestinal and biliary dyskinesia

Dysbiosis and nutrition in steatotic liver disease: addressing the unrecognized small intestinal bacterial overgrowth (SIBO) challenge.

Steatotic liver disease (SLD) is characterized by hepatic fat accumulation, potentially causing major consequences such as liver decompensation. Currently, we lack medications for the treatment of SLD. Therapeutic recommendations for patients include a hypocaloric diet, weight loss, and physical activity. In particular, the Mediterranean diet is frequently recommended. However, this diet might exacerbate intestinal problems in a subset of patients with coexisting small intestinal bacterial overgrowth (SIBO). Previous studies have reported that SIBO is more predominant in patients with fatty liver than in healthy individuals. Both our research and the findings of others have highlighted a challenge related to nutritional therapy in patients with fatty liverwho also suffer from SIBO inasmuch as SIBO induces several phenomena (like bloating or abdominal pain) that can adversely affect patients' quality of life and might be exacerbated by the Mediterranean diet. This may lower their adherence to the intervention. As a solution, we suggest introducing additional diagnostics (e.g., breath test) in patients with SLD who complain of SIBO-like symptoms. The next step is to modify their diets temporarily starting with several weeks of "elimination and sanitation." This would involve restricting products rich in fermentable sugars and polyols, while simultaneously treating the bacterial overgrowth. In summary, while the hypocaloric Mediterranean diet is beneficial for patients with fatty liver, those with coexisting SIBO may experience exacerbated symptoms. It is vital to consider additional diagnostics and dietary modifications for this subset of patients to address both liver and intestinal health concurrently.

Analyzing the bibliometrics of brain-gut axis and Parkinson's disease.

Parkinson's disease (PD), characterized by the loss of dopaminergic neurons, is a progressive neurodegenerative disorder. Recent research has revealed a significant connection between gut microbiota and PD. To gain insight into research interests, disciplinary contexts, and potential future directions, a comprehensive bibliometric analysis was conducted on the brain-gut axis and PD literature published between 2014 and 2023. Relevant literature records were gathered from the Web of Science Core Collection on August 11, 2023. The data were then analyzed by Biblioshiny R packages and VOSviewer (version 1.6.19). The dataset revealed an upward trend in annual scientific publications on the brain-gut axis and PD, with an annual growth rate of 50.24%. China, the United States, and Italy were the top three most productive countries/regions. The journal "International Journal Of Molecular Sciences" published the most articles, while "Movement Disorders" received the highest number of citations. Professor Keshavarzian A emerged as the most prolific author, while Professor Scheperjans F held the highest h-index. Keyword analysis highlighted "alpha-synuclein" as the most frequent term, with "mouse model," "inflammation," and "risk" as emerging research topics. Additionally, "central nervous system" and "intestinal bacterial overgrowth" attracted increasing attention. This study examined current trends and hotspots in the bibliometric landscape of the brain-gut axis and PD research. Future research directions should explore the functional and metabolic activities of gut microbiota. Additionally, transitioning from observational to interventional study designs offers the potential for personalized interventions and disease prediction. These findings can guide researchers in navigating the latest developments and shaping the future directions of this field.

Agentes infecciosos y malabsorción intestinal

Intestinal malabsorption syndromes pose a diagnostic and treatment challenge in the routine clinical practice of both primary care physicians and gastroenterology specialists. There are multiple causes of intestinal malabsorption. This update will attempt to address, in a practical manner, three entities that are clinically relevant, either because of their increasing prevalence or because of their diagnostic and treatment complexity: intestinal bacterial overgrowth, intestinal parasite infections, and intestinal immunodeficiencies.Bacterial overgrowth is a highly prevalent disease in developed countries that causes various gastrointestinal symptoms. In developing countries, intestinal parasite infections are a significant cause of morbidity. It affects 24% of the world's population. The gastrointestinal symptomatology of both diseases is associated with structural and functional disorders of the small intestine, systemic conditions, medications, and immunological disorders. Immunodeficiencies are a less frequent but no less important disorder, given the morbidity and mortality they entail. This update will address these conditions and their gastrointestinal symptoms and will attempt to answer questions, especially regarding diagnostic and treatment, that these diseases raise in clinical practice.

Liquid Thyroxine Improves Outcomes in Hypothyroid Patients With Small Intestinal Bacterial Overgrowth and Irritable Bowel Syndrome

ObjectiveMalabsorption of levothyroxine (LT4) is often seen in patients with hypothyroidism and gastrointestinal (GI) conditions. Our study was designed to establish the prevalence of small intestinal bacterial overgrowth (SIBO) in patients with hypothyroidism and irritable bowel syndrome (IBS), and to demonstrate that liquid LT4 is more consistently absorbed vs tablet, leading to improvement in thyroid and GI symptoms. MethodsThis was a single-center, open label, prospective cohort study of liquid LT4 in 75 adult patients with hypothyroidism and IBS. Patients were transitioned from LT4 tablets to solution at equivalent dosing. Patients returned at 6 and 12 weeks for repeat thyroid levels and completion of validated questionnaires. A standard 2-hour SIBO breath test was administered at Week 6. Patients recorded daily stool appearance and frequency. ResultsPrevalence of SIBO was 65.3%. Liquid LT4 normalized thyroid stimulating hormone (TSH) in a higher percentage of patients vs tablet (77.55% vs 57.14%); significantly decreased TSH in subjects with SIBO; improved hypothyroid symptoms, IBS symptoms, stool appearance in all groups, and significantly altered bowel frequency among those with SIBO. ConclusionSmall intestinal bacterial overgrowth (SIBO) is common in patients with hypothyroidism and IBS. Among SIBO patients, LT4 tablets were inefficiently absorbed, leading to suboptimal thyroid control; however, transitioning from LT4 tablets to solution normalized TSH and improved hypothyroid symptoms. Liquid LT4 also significantly improved GI symptoms in all patients with hypothyroidism and IBS, regardless of SIBO status. Additionally, 1 in 5 patients had complete resolution of IBS symptoms after switching from LT4 tablets to solution, independent of changes in TSH.

Cystic fibrosis and fat malabsorption: Pathophysiology of the cystic fibrosis gastrointestinal tract and the impact of highly effective CFTR modulator therapy.

Cystic fibrosis (CF) is a progressive, genetic, multi-organ disease affecting the respiratory, digestive, endocrine, and reproductive systems. CF can affect any aspect of the gastrointestinal (GI) tract, including the esophagus, stomach, small intestine, colon, pancreas, liver, and gall bladder. GI pathophysiology associated with CF results from CF membrane conductance regulator (CFTR) dysfunction. The majority of people with CF (pwCF) experience exocrine pancreatic insufficiency resulting in malabsorption of nutrients and malnutrition. Additionally, other factors can cause or worsen fat malabsorption, including the potential for short gut syndrome with a history of meconium ileus, hepatobiliary diseases, and disrupted intraluminal factors, such as inadequate bile salts, abnormal pH, intestinal microbiome changes, and small intestinal bacterial overgrowth. Signs and symptoms associated with fat malabsorption, such as abdominal pain, bloating, malodorous flatus, gastroesophageal reflux, nausea, anorexia, steatorrhea, constipation, and distal intestinal obstruction syndrome, are seen in pwCF despite the use of pancreatic enzyme replacement therapy. Given the association of poor nutrition status with lung function decline and increased mortality, aggressive nutrition support is essential in CF care to optimize growth in children and to achieve and maintain a healthy body mass index in adults. The introduction of highly effective CFTR modulator therapy and other advances in CF care have profoundly changed the course of CF management. However, GI symptoms in some pwCF may persist. The use of current knowledge of the pathophysiology of the CF GI tract as well as appropriate, individualized management of GI symptoms continue to be integral components of care for pwCF.

Gut Microbiota and Biomarkers of Intestinal Barrier Damage in Cirrhosis.

Gut dysbiosis and subclinical intestinal damage are common in cirrhosis. The aim of this study was to examine the association of intestinal damage biomarkers (diamine oxidase [DAO], claudin 3, and intestinal fatty acid binding protein [I-FABP; FABP2]) with the state of the gut microbiota in cirrhosis. The blood levels of DAO were inversely correlated with blood levels of claudin 3, lipopolysaccharide (LPS), presepsin, TNF-α, and the severity of cirrhosis according to Child-Pugh scores. The blood level of I-FABP was directly correlated with the blood level of claudin 3 but not with that of DAO. Patients with small intestinal bacterial overgrowth (SIBO) had lower DAO levels than patients without SIBO. There was no significant difference in claudin 3 levels and I-FABP detection rates between patients with and without SIBO. The DAO level was directly correlated with the abundance of Akkermansiaceae, Akkermansia, Allisonella, Clostridiaceae, Dialister, Lactobacillus, Muribaculaceae, Negativibacillus, Ruminococcus, Thiomicrospiraceae, Verrucomicrobiae, and Verrucomicrobiota; and it was inversely correlated with the abundance of Anaerostipes, Erysipelatoclostridium, and Vibrio. The I-FABP level was directly correlated with Anaerostipes, Bacteroidia, Bacteroidota, Bilophila, Megamonas, and Selenomonadaceae; and it was inversely correlated with the abundance of Brucella, Pseudomonadaceae, Pseudomonas, and Vibrionaceae. The claudin 3 level was directly correlated with Anaerostipes abundance and was inversely correlated with the abundance of Brucella, Coriobacteriia, Eggerthellaceae, and Lactobacillus.

A multi-national survey to identify clinicians’ perspectives concerning Proton Pump inhibitors in patients with systemic sclerosis

ObjectivesProton Pump Inhibitors (PPIs) are widely used in SSc for gastroesophageal reflux disease (GERD). However, there is little evidence to support their empirical use and long-term safety has been questioned. Our objective was to better describe clinicians’ attitudes toward PPIs prescription and use in SSc patients. MethodsClinicians involved in the care of SSc patients were invited through international physician networks and social media to participate in an online survey. ResultsResponses from 227 clinicians from 36 countries were evaluable. The majority ‘agreed’ (41.4 %) or ‘strongly agreed’ (45.4 %) that GERD is a major cause of morbidity in SSc. Lifestyle modifications are seldom (16 %) considered effective. Only half ‘agreed’ (43 %) or ‘strongly agreed’ (11 %) there is solid evidence supporting PPIs efficacy in SSc. The most common reasons for PPIs prescription were symptomatic GERD unresponsive to lifestyle modification (95 %), objective evidence of GERD (82 %), and hoarseness or respiratory symptoms (71 %). There are variable concerns about PPIs long-term safety in SSc. The three highest (mean) reasons (0–10, here 10 is ‘very concerned’) were: small intestinal bacterial overgrowth (5.5), osteoporosis (5.4), and drug interactions (5.2). There are significant differences in attitudes towards surgery for refractory GERD, and concerns about potential complications. PPIs may have a putative role for disease modification (e.g., ILD and calcinosis), and the role of immunosuppression is uncertain for GI (gastrointestinal) disease in SSc. ConclusionPPIs are frequently prescribed in SSc. Side effects are a recognized concern, especially regarding long-term therapy. There is significant variation in attitudes towards surgical intervention. Future research and practical treatment recommendation for PPIs in SSc are urgently needed.

Small Intestinal Bacterial Overgrowth in Various Specialties of Medical Practice (Literature Review and Expert Council Resolution)

Aim: to discuss current views on the clinical significance, diagnostic opportunities, and therapeutic approaches in the treatment of small intestinal bacterial overgrowth (SIBO) as an important component in the gut microbiota function assessment, to assess the awareness of physicians and the opportunities in the diagnosis and treatment of this disease in patients in the Federal districts of the Russian Federation, as well as to present the proceedings of the Expert Council held on December 16, 2023 in Moscow.Key points. SIBO is a common syndrome often associated with irritable bowel syndrome, liver cirrhosis, asthma, and congestive heart failure, being also a predictor of early death in the elderly. Today, in many regions of the Russian Federation, there are limitations for instrumental diagnosis of this disease — lack of awareness among doctors, unavailability of gas analyzers for diagnosing SIBO, lack of information about the need to diagnose SIBO in the standards of compulsory health insurance. Rifaximin is the first-line treatment due to the highest therapeutic efficacy. One of the ways to increase the efficacy of SIBO treatment is to include strain-specific probiotics in the treatment regimen. Saccharomyces boulardii CNCM I-745 is thought to be the most studied, promising probiotic. The review also presents statistical data on the issues in the diagnosis and treatment of SIBO in the regions of the Russian Federation.Conclusion. Optimization of approaches to the diagnosis and treatment of SIBO, the development of domestic gas analyzers, increasing the awareness of physicians in all regions of the Russian Federation, as well as the development and optimization of clinical recommendations appear to be necessary measures to increase the effectiveness of medical care, the duration and quality of life of the Russian population. These goals can be achieved within the framework of Federal programs under the supervision of specialized reference centers of the Ministry of Health of the Russian Federation.

Influence of Helicobacter pylori Infection and Eradication on Small Intestinal Bacterial Overgrowth and Abdominal Symptoms.

The relationship between Helicobacter pylori (H. pylori) infection and small intestinal bacterial overgrowth (SIBO) has attracted attention recently. To analyze the influence of H. pylori infection and eradication on SIBO, IMO, and abdominal symptoms. Patients with gastrointestinal symptoms were tested for 13C urea breath test and if positive, treated with bismuth-based quadruple therapy. Lactulose hydrogen methane breath test (HMBT) was performed and symptoms were assessed using gastrointestinal symptom rating scale (GSRS) before and 6weeks after eradication. Of the 102 subjects, 53 were H. pylori positive. The prevalence of SIBO and IMO were higher in patients with H. pylori infection than in those without infection (49.1% vs 24.5%, P = 0.019 for SIBO; 24.5% vs 8.2%, P = 0.027 for IMO). GSRS scores were similar between H. pylori-infected and uninfected patients (2 (IQR: 1;3) vs 2 (IQR: 1;2), P = 0.211). Patients with SIBO or IMO presented higher GSRS scores than patients with both SIBO and IMO negative (2 (IQR: 2;3), 2 (IQR: 2;3) vs 2 (IQR: 1;2), P = 0.011, 0.001, respectively). For the 50 patients who successfully eradicated H. pylori, the response rates for SIBO and IMO were 66.7% and 76.9%, respectively. GSRS scores also significantly decreased (2 (IQR: 1;3) to 0 (IQR: 0;1), P < 0.001) after eradication. Helicobacter pylori infection was associated with higher prevalence of SIBO and IMO, both of which led to more pronounced abdominal symptoms. H. pylori eradication also achieved therapeutic effects on SIBO and IMO, accompanied by relief of abdominal symptoms.

Efficacy and Safety of a Probiotic Containing Saccharomyces boulardii CNCM I-745 in the Treatment of Small Intestinal Bacterial Overgrowth in Decompensated Cirrhosis: Randomized, Placebo-Controlled Study

(1) Background: The aim was to evaluate the effectiveness of the probiotic containing Saccharomyces boulardii in the treatment of small intestinal bacterial overgrowth (SIBO) in patients with decompensated cirrhosis. (2) Methods: This was a blinded, randomized, placebo-controlled study. (3) Results: After 3 months of treatment, SIBO was absent in 80.0% of patients in the probiotic group and in 23.1% of patients in the placebo group (p = 0.002). The patients with eliminated SIBO had decreased frequency of ascites and hepatic encephalopathy, the increased platelets and albumin levels, the decreased blood levels of total bilirubin, biomarkers of bacterial translocation (lipopolysaccharide [LPS]) and systemic inflammation (C-reactive protein), and positive changes in markers of hyperdynamic circulation compared with the state at inclusion. There were no significant changes in the claudin 3 level (the intestinal barrier biomarker) in these patients. No significant changes were observed in the group of patients with persistent SIBO. The serum level of nitrate (endothelial dysfunction biomarker) was lower in patients with eradicated SIBO than in patients with persistent SIBO. One (5.3%) patient with eradicated SIBO and six (42.9%) patients with persistent SIBO died within the first year of follow-up (p = 0.007). (4) Conclusions: SIBO eradication was an independent predictor of a favorable prognosis during the first year of follow-up.

Prospective Monitoring of Small Intestinal Bacterial Overgrowth After Gastric Bypass: Clinical, Biological, and Gas Chromatographic Aspects.

Obesity is a predisposing factor for small intestinal bacterial overgrowth (SIBO). The aim of this study was to prospectively evaluate the prevalence of SIBO as well as its clinical, biological, and nutritional aspects before and up to 24months after a Roux-en-Y gastric bypass (RYGB) surgery. Fifty-one patients (mean BMI 46.9kg/m2, 66.7% women) requesting RYGB were included between 2016 and 2020. Each patient underwent a glucose breath test, a standardized interrogation on functional digestive signs, a dietary survey, a blood test, a fecalogram, and anthropometric data gathering. These investigations were carried out before surgery and at 1, 3, 6, 9, 12, 18, and 24months after RYGB. Before surgery, we found a prevalence of 17.6% of SIBO (95% CI = [8.9%; 31.4%]). After RYGB, at the end of 24months of follow-up, 89.5% of patients developed SIBO. Anal incontinence appeared to be very frequent after surgery, affecting 18.8% of our population 18months after surgery. We observed positive steatorrhea after surgery with an average of 11.1g of lipids/24h despite a significant limitation of dietary lipids (p = 0.0282). Our study corroborates data in the literature on the prevalence of SIBO in severe obesity patients. For the first time, we observed the sudden appearance of SIBO after RYGB, with a correlation between exhaled hydrogen on a breath test and lipid malabsorption on the fecalogram. As a result, these patients develop fatty diarrhea, with frequent fecal incontinence.

Symptomatic Response to Antibiotics in Patients With Small Intestinal Bacterial Overgrowth: A Systematic Review and Meta-analysis.

We performed a systematic review and meta-analysis evaluating the symptomatic response rate to antibiotics in patients with small intestinal bacterial overgrowth (SIBO). Similarly, we performed a meta-analysis on the symptomatic response to antibiotics in irritable bowel syndrome (IBS) patients with and without SIBO. MEDLINE, EMBASE, Web of Science, and Cochrane databases were searched from inception to March 2021. Randomized controlled trials and prospective studies reporting dichotomous outcomes were included. There were 6 studies included in the first meta-analysis comparing the efficacy of antibiotics to placebo or no antibiotic. This included 196 patients, of whom 101 received antibiotics and 95 received placebo or no antibiotics. Significantly more patients improved with antibiotics (relative risk [95% CI] = 2.46 [1.33-4.55], P = 0.004). There were 4 studies included in the analysis comparing symptomatic response rates in IBS patients with or without SIBO with 266 IBS patients, of whom 172 had SIBO and 94 did not. The pooled response rate for symptomatic response was 51.2% in the SIBO group vs 23.4% in the no SIBO group, respectively. Significantly more IBS patients with SIBO responded to antibiotics compared to those without SIBO (relative risk [95% CI] = 2.07 [1.40-3.08], P = 0.0003). Antibiotics appear to be efficacious in treating SIBO, although small sample sizes and poor data quality limit this interpretation. Symptomatic response rates also appear to be higher in IBS patients with SIBO. This may be the first example of precision medicine in IBS as opposed to our current empiric treatment approach. Large-multicenter studies are needed to verify the results.

Evaluation of probiotics in the treatment of hypothyroidism in early pregnancy combined with small intestinal bacterial overgrowth.

The aim of this study was to investigate the association between hypothyroidism in early pregnancy and small intestinal bacterial overgrowth (SIBO) and the effect of probiotics. Patients with hypothyroidism in early pregnancy and normal pregnant women during the same period were included in the methane-hydrogen breath test to compare the incidence of SIBO, smoothed curve fit, and differences in clinical symptoms. For those who combined with SIBO, the rate of clinical symptom conversion, thyroid hormones, and changes in associated inflammatory indexes were compared after 21 days of treatment with probiotics on top of conventional levothyroxine sodium tablets. The results are as follows: (1) The incidence of combined SIBO in patients with hypothyroidism in pregnancy was 56.0%, significantly higher than the 28.0% of normal pregnant women during the same period. (2) The highest value of hydrogen plus methane gas in 90 min in pregnancy hypothyroid patients showed a significant negative correlation with FT4 (p < .001, SD = 0.169). (3) Abdominal distension symptoms were significantly increased in both groups after combined SIBO (p = .036, p = .025), and the conversion rate after treatment was 69.2% and 75.0%, respectively. (4) In hypothyroidism, pregnancy combined with SIBO, TSH, and CRP was higher before treatment (p = .001, p = .012) and decreased significantly after treatment (p = .001, p = .008). Hypothyroidism in early pregnancy is associated with SIBO, and probiotic treatment is significantly effective.

Efficacy and safety of rifaximin in patients with chronic intestinal pseudo-obstruction: a randomized, double-blind, placebo-controlled, phase II-a exploratory trial.

Chronic intestinal pseudo-obstruction (CIPO) is a rare intractable disease with limited treatment options. Small intestinal bacterial overgrowth (SIBO) often co-occurs with several diseases, including CIPO. While rifaximin (RFX) is effective in treating SIBO, its efficacy for CIPO remains unclear. Here, we aimed to investigate the efficacy and safety of RFX in adult patients with CIPO. Twelve patients were randomly assigned to receive RFX (400 mg three times daily, n=8) or a placebo (PBO, n=4) for 4 weeks. The global symptom score for abdominal bloating (GSS-bloating) and an original whole gastrointestinal symptoms score (O-WGSS) were collected, and a glucose hydrogen breath test (GHBT) and abdominal computed tomography (CT) were performed. No significant differences were observed in the primary endpoint. GSS-bloating improved by 75% and 25% in the PBO and RFX groups, respectively, and O-WGSS improved by 25% in both groups. No significant differences were observed in secondary and other endpoints, including the SIBO eradication rate in the GHBT and small intestinal volume on CT. In a post hoc analysis of SIBO-positive patients with CIPO (4/4 and 4/8 in the PBO and RFX groups), SIBO was eradicated in 25% and 75% of the patients (PBO and RFX groups, respectively) at the end of treatment, indicating a high eradication rate in the RFX group. Furthermore, the small intestinal gas volume decreased in the RFX group, and no severe adverse events occurred. Although no significant improvements were observed in subjective indicators, RFX may be beneficial in alleviating SIBO and reducing the small intestinal gas volume in SIBO-positive patients with CIPO.

Impact of small intestinal bacterial overgrowth on systemic inflammation, circulatory and renal function, and liver fibrosis in patients with cirrhosis and ascites.

Small intestinal bacterial overgrowth (SIBO) occurs frequently in patients with cirrhosis, particularly in those with ascites, and promotes the translocation of gut-derived bacterial products into the portal and systemic circulation. We investigated the effects of SIBO on systemic inflammatory activity, circulatory and renal function, and the degree of liver fibrosis in patients with cirrhosis and ascites. Eighty patients with cirrhosis and ascites were prospectively enrolled. SIBO was determined by lactulose breath test. Serum levels of lipopolysaccharide-binding protein (LBP), tumor necrosis factor-α, and interleukin-6, mean arterial pressure (MAP), cardiac output (CO) by echocardiography, systemic vascular resistance (SVR) as MAP/CO ratio, plasma renin activity (PRA), plasma aldosterone, radioisotope-assessed glomerular filtration rate (GFR), and liver stiffness by shear wave elastography were evaluated. SIBO was detected in 58 patients (72.5%). Compared to patients without SIBO, those diagnosed with SIBO had significantly higher LBP levels (P<0.001), significantly lower MAP (P<0.001) and SVR (P<0.001), and significantly higher CO (P=0.002) and PRA (P<0.001). Patients with SIBO had significantly lower GFR (P=0.02) and higher liver stiffness (P=0.04) compared to those without SIBO. The presence of SIBO was independently associated with LBP (P=0.007) and PRA (P=0.01). Among patients with SIBO, peak breath hydrogen concentration was significantly correlated with serum LBP (P<0.001), MAP (P<0.001), CO (P=0.008), SVR (P=0.001), PRA (P=0.005), plasma aldosterone (P<0.001), GFR (P<0.001), and liver stiffness (P=0.004). SIBO in patients with cirrhosis and ascites may predispose to greater systemic inflammation, circulatory and renal dysfunction, and more advanced liver fibrosis.