Small intestinal bacterial overgrowth

The relationship between small intestinal bacterial overgrowth and constipation in children - a comprehensive review

Small intestinal bacterial overgrowth (SIBO) is characterized by an increase in the bacterial population of the small intestine due to an imbalance between the amount of bacteria and the intestinal barrier. Pediatric SIBO presents with a wide spectrum of symptoms, ranging from mild gastrointestinal complaints to malabsorption or malnutrition. Breath tests are commonly used as noninvasive diagnostic tools for SIBO, but a standardized methodology is currently unavailable. Intestinal flora produces methane which slows intestinal transit and increases the contractile activity of small intestine. Emerging literature suggests a correlation between overgrowth of methanogenic bacteria in the intestines and constipation. Treatment of SIBO involves administration of antibacterial therapy in addition to management of underlying conditions and optimal dietary adjustments. However, research on antibiotic treatment for pediatric patients with constipation and SIBO is limited and has yielded conflicting results. In the current review, we summarize the state-of-the-art of the field and discuss previous treatment attempts and currently used regimens for SIBO patients with constipation, with a focus on pediatric populations.

Subnormal Serum Liver Enzyme Levels: A Review of Pathophysiology and Clinical Significance

Subnormal levels of liver enzymes, below the lower limit of normal on local laboratory reports, can be useful diagnostically. For instance, subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney disease. Subnormal alkaline phosphatase levels may indicate the presence of hypophosphatasia, Wilson's disease, deficiencies of divalent ions, or malnutrition. Subnormal levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis, the use of certain medications, and in bone disease. Finally, subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic anemia. The aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

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

BACKGROUND AND AIMS

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 24 months after a Roux-en-Y gastric bypass (RYGB) surgery.

PATIENTS AND METHODS

Fifty-one patients (mean BMI 46.9 kg/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 24 months after RYGB.

RESULTS

Before surgery, we found a prevalence of 17.6% of SIBO (95% CI = [8.9%; 31.4%]). After RYGB, at the end of 24 months of follow-up, 89.5% of patients developed SIBO. Anal incontinence appeared to be very frequent after surgery, affecting 18.8% of our population 18 months after surgery. We observed positive steatorrhea after surgery with an average of 11.1 g of lipids/24 h despite a significant limitation of dietary lipids (p = 0.0282).

CONCLUSION

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.

Prevalence, risk factors, and treatment of small intestinal bacterial overgrowth in children

Small intestinal bacterial overgrowth (SIBO) is defined as the presence of an excessive number of bacteria within the small bowel. Pediatric SIBO is a heterogeneous disorder that manifests as various symptoms ranging from mild gastrointestinal symptoms to malabsorption or malnutrition. The carbohydrate breath test is a commonly used, safe, and noninvasive diagnostic test; however, a standardized methodology is lacking. Multiple factors, such as neuromuscular disorders, systemic diseases, chronic drug use, or altered intestinal anatomy that disturb intestinal motility or induce an abnormality in the body's defense systems against intestinal bacteria, predispose children to SIBO. The high prevalence and similar symptoms of SIBO in functional gastrointestinal disorders, including irritable bowel syndrome, suggest an association between them. The principles of treatment include managing predisposing conditions, nutritional support, symptom control, and antibacterial treatment. Rifaximin is the most commonly used drug. To date, studies of antibiotic treatment in pediatric populations with irritable bowel syndrome or SIBO are lacking and have shown mixed results. Here we review the prevalence, diagnostic tests, and treatment results in pediatric populations.

The Role of Endoscopic Management in Afferent Loop Syndrome

Afferent loop syndrome (ALS) is a morbid complication that may occur after gastrectomy and gastrojejunostomy reconstruction. The aim of this article is to review the different endoscopic treatment options of ALS. We describe the evolution of the endoscopic treatment of ALS and its limitations despite the overall propitious profile. We analyze the advantages of endoscopic ultrasound-guided entero-enterostomy (EUS EE) over enteroscopy-guided intervention, and the clinical outcomes of EUS EE. We expound on pre-procedural considerations, intra-procedural techniques and post-procedural care following EUS EE. We conclude that given the simplification of the technique and the ability to place a stent away from the tumor, EUS EE is a promising technique that will likely be established as the treatment of choice for ALS.

Alterations of gut microbiome and effects of probiotic therapy in patients with liver cirrhosis: A systematic review and meta-analysis

BACKGROUND

Alterations in the gut microbiome usually occur in liver cirrhosis. Gut microbiome dysregulation damages the liver and accelerates the development of liver fibrosis. Probiotic treatment has gradually become a major method for improving the prognosis of liver cirrhosis and reducing its complications. However, alterations in the gut microbiome have revealed different results, and the therapeutic effects of various probiotics are inconsistent.

METHODS

We searched the PubMed, Medline, EMBASE, ScienceDirect, and Cochrane databases up to August 2022 and conducted a systematic review and meta-analysis of 17 relevant studies.

RESULTS

The counts of Enterobacter (standardized mean difference [SMD] -1.79, 95% confidence interval [CI]: -3.08 to -0.49) and Enterococcus (SMD -1.41, 95% CI: -2.26 to -0.55) increased significantly in patients with cirrhosis, while the counts of Lactobacillus (SMD 0.63, 95% CI: 0.12-1.15) and Bifidobacterium (SMD 0.44, 95% CI: 0.12-0.77) decreased significantly. Blood ammonia (weighted mean difference [WMD] 14.61, 95% CI: 7.84-21.37) and the incidence of hepatic encephalopathy (WMD 0.40, 95% CI: 0.27-0.61) were significantly decreased in the probiotic group. As for mortality (MD 0.75, 95% CI: 0.48-1.16) and the incidence of spontaneous bacterial peritonitis (WMD -0.02, 95% CI: -0.07 to 0.03), no significant differences were found between the probiotic and placebo groups.

CONCLUSION

In summary, the gut microbiome in cirrhosis manifests as decreased counts of Lactobacillus and Bifidobacterium and increased counts of Enterobacter and Enterococcus. Targeted supplementation of probiotics in cirrhosis, including Lactobacillus combined with Bifidobacterium or Bifidobacterium alone, can reduce blood ammonia and the incidence of hepatic encephalopathy. The effect is similar to that of lactulose, but it has no obvious effect on mortality and spontaneous bacterial peritonitis.

Persistent Inflammation Initiated by TORCH Infections and Dysbiotic Microbiome in Autism Spectrum Disorders: A Prospect for Future Interventions

Autism spectrum disorders (ASD) are a range of neurodevelopmental conditions that are clinically present early in childhood with the symptoms of social withdrawal and repetitive behavior. Despite an extensive research on ASD, no commonly accepted theory on the disease etiology exists. Hence, we reviewed several scientific publications, including reviews, preclinical and clinical investigations, and published hypotheses to analyze various opinions on the nature and cause of the disorder. Many studies suggest that infections and inflammation during pregnancy play a significant role in genetic and epigenetic changes in the developing fetus, resulting in an autistic phenotype in a child. Still, there is a lack of comprehensive literature about the multitude of autism inducing factors. Therefore, this article reviews and discusses available scientific evidence on the roles of viral, bacterial, fungal, and parasitic infections, overactivation of the immune system, and intestinal microflora in the pathogenesis and clinical manifestation of ASD. The overview of the scientific publications, including our own studies, suggests that TORCH infections, imbalanced microbiome, and persistent inflammation are significantly associated with the disruption of the social domain in ASD children. The ASD-related changes begin prenatally as maternal-to-fetal immune activation triggered by infection. It results in continuous low-grade inflammation and oxidative stress in a fetus, causing germline and somatic genetic changes in the developing brain and the establishment of the dysregulated immune system. These changes and dysregulations result in central and peripheral nervous systems dysfunctions as well as other comorbid conditions found in autistic children.

Asian-Pacific consensus on small intestinal bacterial overgrowth in gastrointestinal disorders: An initiative of the Indian Neurogastroenterology and Motility Association

In the clinical setting, small intestinal bacterial overgrowth (SIBO) is a frequent, but under-diagnosed entity. SIBO is linked to various gastrointestinal (GI) and non-GI disorders with potentially significant morbidity. The optimal management of SIBO is undefined while there is a lack of published consensus guidelines. Against this background, under the auspices of the Indian Neurogastroenterology and Motility Association (INMA), formerly known as the Indian Motility and Functional Diseases Association (IMFDA), experts from the Asian-Pacific region with extensive research and clinical experience in the field of gut dysbiosis including SIBO developed this evidence-based practice guideline for the management of SIBO utilizing a modified Delphi process based upon 37 consensus statements, involving an electronic voting process as well as face-to-face meetings and review of relevant supporting literature. These statements include 6 statements on definition and epidemiology; 11 on etiopathogenesis and pathophysiology; 5 on clinical manifestations, differential diagnosis, and predictors; and 15 on investigations and treatment. When the proportion of those who voted either to accept completely or with minor reservations was 80% or higher, the statement was regarded as accepted. The members of the consensus team consider that this guideline would be valuable to inform clinical practice, teaching, and research on SIBO in the Asian-Pacific region as well as in other countries.

Association of small intestinal bacterial overgrowth with nonalcoholic fatty liver disease in children: A meta-analysis

It has been suggested that small intestinal bacterial overgrowth (SIBO) could cause nonalcoholic fatty liver disease (NAFLD), but this association was not examined in children by meta-analysis. This meta-analysis aimed to determine the association between SIBO and NAFLD in children. The electronic databases PubMed, Embase, and Cochrane Library were searched for studies published before April 22, 2021. The outcome was the association between SIBO and NAFLD. Three studies and 205 children were included. All three studies reported the association between SIBO and NAFLD. Children with SIBO were more likely to have NAFLD (odds ratio = 5.27, 95% confidence interval (CI): 1.66-16.68, P<0.001; I2 = 63.5%, Pheterogeneity = 0.065). When directly pooling the reported relative risks (RR) from two studies, children with NAFLD had an over 2-fold increased relative risk of developing SIBO (RR = 2.17, 05%CI: 1.66-2.82, P<0.001; I2 = 0.0%, Pheterogeneity = 0.837). This meta-analysis reports a possible association between SIBO and NAFLD in children.

Small Intestinal Bacterial Overgrowth in Subclinical Hypothyroidism of Pregnant Women

OBJECTIVE

To evaluate the small intestinal bacterial overgrowth (SIBO) of subclinical hypothyroidism of pregnant women, and explore their possible relevance.

METHODS

In total, 224 pregnant women with subclinical hypothyroidism during pregnancy (study group) and 196 pregnant women whose thyroid function was normal (control group) were enrolled in this study. Lactulose-based hydrogen and methane breath test was performed to evaluate the growth of intestinal bacteria. The serum-free thyroid hormone (FT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb), body mass index (BMI) and gastrointestinal symptoms were detected and recorded.

RESULTS

The positive rates of SIBO were 56.7% and 31.6% in study group and control group, respectively. The levels of C response protein (CRP), abdominal distension and constipation in study group were higher than those in the control group. The risk of abdominal distension and constipation in SIBO-positive pregnant women were higher than that in SIBO-negative pregnant women, and the BMI of SIBO-positive patients in the two groups was lower than that of SIBO-negative patients in each group. In addition, the TPOAb-positive rate and TSH levels were higher but the FT4 level was lower in SIBO-positive patients compared to SIBO-negative patients in study group.

CONCLUSION

The occurrence of subclinical hypothyroidism is related to SIBO, and the excessive growth of small intestinal bacteria may affect gastrointestinal symptoms.

CLINICAL TRIAL

http://www.chictr.org.cn/index.aspx, identifier ChiCTR1900026326.

Afferent Loop Syndrome with Intestinal Ischemia due to Internal Hernia after Whipple Operation for T2N1M0 Pancreatic Cancer

Afferent loop syndrome is an uncommon complication of Whipple procedure. The often vague and non-specific presentation results in difficulty and/or delay in diagnosis, which may lead to bowel ischemia or perforation. CT can demonstrate characteristic features, yield the diagnosis of afferent loop syndrome, and predict the cause before surgical intervention. We present a rare etiology of acute afferent loop syndrome in a patient 6 weeks after Whipple procedure who was reportedly recovering well, which resulted in prompt surgical intervention.

Diagnosis and treatment of the afferent loop syndrome

Afferent loop syndrome (ALS) is a mechanical complication that arises after gastric surgery with gastrojejunostomy reconstruction. This condition was first described in 1950 by Roux, Pedoussaut, and Marchal to post-gastrectomy patients with bilious vomiting. Acute ALS is associated with complete obstruction and considered a surgical emergency, whereas chronic ALS is mostly related to partial obstruction of the afferent loop. The delay in diagnosis may lead to intestinal ischemia, perforation and can be associated with a high mortality rate up to 60%. Surgery is usually the mainstay treatment of ALS, but endoscopic therapy, including stent placement in malignancy-related, anastomotic stricture dilation, has been evolving over the past recent years.

Small bowel knots

INTRODUCTION

Intertwining of bowel loops to form a knot is very rare cause of intestinal obstruction. Among intestinal knots, ileoileal knotting is the most rare, with only a handful of cases reported in literature. We present a rare case of ileoileal knotting and review of small bowel knots. The aim of this review was to summarise the existing evidence on small bowel knots and to postulate the possible mechanisms for knotting.

METHODS

A systematic search was conducted for literature published up to December 2019 using MEDLINE, PubMed and Google Scholar databases, together with the references of the full-text articles retrieved. Papers with case reports of small bowel knots were considered to be eligible for inclusion in the review.

FINDINGS

A total of 14 case reports were evaluated. There was no clear predilection for age or sex. Mostly cases were from Asia and Africa with no cases from the West. The presenting complaints were abdominal pain (93%), vomiting (64%), abdominal distention (57 %) and obstipation (43%). The bowel was gangrenous in 78% of cases. All underwent exploration, with the majority requiring resection and anastomosis of the involved segment.

CONCLUSION

Ileoileal knotting is a very rare cause of intestinal obstruction. Possible mechanisms include loaded bowel with longer mesentery, vigorous peristalsis, single bulky meal, pregnancy and intussusception. The condition is extremely difficult to diagnose preoperatively and it is usually diagnosed intraoperatively. The standard of treatment is resection of gangrenous part and anastomosis.

Total body irradiation induced mouse small intestine senescence as a late effect

Radiation can induce senescence in many organs and tissues; however, it is still unclear how radiation stimulates senescence in mouse small intestine. In this study, we use the bone marrow transplantation mouse model to explore the late effects of total body irradiation on small intestine. Our results showed that almost all of the body hairs of the irradiated mice were white (which is an indication of aging) 10 months after the exposure to radiation. Furthermore, compared with the age-matched control mice, there were more SA-β-galactosidase (SA-β-gal)-positive cells and an upregulation of p16 and p21 in 8 Gy-irradiated mice intestinal crypts, indicating that radiation induced senescence in the small intestine. Intestinal bacterial flora profile analysis showed that the diversity of the intestinal bacterial flora decreased in irradiated mice; in addition it showed that the principal components of the irradiated and control mice differed: there was increased abundance of Bacteroidia and a decreased abundance of Clostridia in irradiated mice. To explore the underlying mechanism, an RNA-sequence was executed; the results suggested that pancreatic secretion, and the digestion and absorption of proteins, carbohydrates, fats and vitamins were damaged in irradiated mice, which may be responsible for the body weight loss observed in irradiated mice. In summary, our study suggested that total body irradiation may induce senescence in the small intestine and damage the health status of the irradiated mice.

Gastrointestinal Malabsorption of Thyroxine

Levothyroxine, a largely prescribed drug with a narrow therapeutic index, is often a lifelong treatment. The therapeutic efficacy of T4 may be marred by behavioral, pharmacologic, and pathologic issues acting as interfering factors. Despite a continuous search for an optimal T4 treatment, a significant number of patients fail to show a complete chemical and/or clinical response to this reference dose of T4. Gastrointestinal malabsorption of oral T4 represents an emerging cause of refractory hypothyroidism and may be more frequent than previously reputed. In this review, we examine the pharmacologic features of T4 preparations and their linkage with the intestinal absorption of the hormone. We have stressed the major biochemical and pharmacologic characteristics of T4 and its interaction with the putative transporter at the intestinal level. We have examined the interfering role of nutrients, foods, and drugs on T4 absorption at the gastric and intestinal levels. The impact of gastrointestinal disorders on T4 treatment efficacy has been also analyzed, in keeping with the site of action and the interfering mechanisms. Based on the evidence obtained from the literature, we also propose a schematic diagnostic workup for the most frequent and often hidden gastrointestinal diseases impairing T4 absorption.

Complications in neonatal surgery

Neonatal surgery is recognized as an independent discipline in general surgery, requiring the expertise of pediatric surgeons to optimize outcomes in infants with surgical conditions. Survival following neonatal surgery has improved dramatically in the past 60 years. Improvements in pediatric surgical outcomes are in part attributable to improved understanding of neonatal physiology, specialized pediatric anesthesia, neonatal critical care including sophisticated cardiopulmonary support, utilization of parenteral nutrition and adjustments in fluid management, refinement of surgical technique, and advances in surgical technology including minimally invasive options. Nevertheless, short and long-term complications following neonatal surgery continue to have profound and sometimes lasting effects on individual patients, families, and society.

Insulin resistance alters hepatic ethanol metabolism: studies in mice and children with non-alcoholic fatty liver disease

OBJECTIVE

Increased fasting blood ethanol levels, suggested to stem from an increased endogenous ethanol synthesis in the GI tract, are discussed to be critical in the development of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to further delineate the mechanisms involved in the elevated blood ethanol levels found in patients with NAFLD.

DESIGN

In 20 nutritionally and metabolically screened children displaying early signs of NAFLD and 29 controls (aged 5-8 years), ethanol plasma levels were assessed. Ethanol levels along the GI tract, in vena cava and portal vein, intestinal and faecal microbiota, and activity of alcohol dehydrogenase (ADH) and cytochrome P450 2E1 (CYP2E1) were measured in wild-type, ob/ob and anti-TNFα antibody (aT) treated ob/ob mice.

RESULTS

Despite not differing in dietary pattern or prevalence of intestinal overgrowth, fasting ethanol levels being positively associated with measures of insulin resistance were significantly higher in children with NAFLD than in controls. Ethanol levels were similar in portal vein and chyme obtained from different parts of the GI tract between groups while ethanol levels in vena cava plasma were significantly higher in ob/ob mice. ADH activity was significantly lower in liver tissue obtained from ob/ob mice in comparison to wild-type controls and ob/ob mice treated with aT.

CONCLUSIONS

Taken together, our data of animal experiments suggest that increased blood ethanol levels in patients with NAFLD may result from insulin-dependent impairments of ADH activity in liver tissue rather than from an increased endogenous ethanol synthesis.

TRIAL REGISTRATION NUMBER

NCT01306396.

Assessment of intestinal malabsorption

Significant efforts have been made in the last decade to either standardize the available tests for intestinal malabsorption or to develop new, more simple and reliable techniques. The quest is still on and, unfortunately, clinical practice has not dramatically changed. The investigation of intestinal malabsorption is directed by the patient's history and baseline tests. Endoscopy and small bowel biopsies play a major role although non-invasive tests are favored and often performed early on the diagnostic algorithm, especially in paediatric and fragile elderly patients. The current clinically available methods and research tools are summarized in this review article.

The Vomiting Patient: Small Bowel Obstruction, Cyclic Vomiting, and Gastroparesis

Vomiting and abdominal pain are common in patients in the emergency department. This article focuses on small bowel obstruction (SBO), cyclic vomiting, and gastroparesis. Through early diagnosis and appropriate management, the morbidity and mortality associated with SBOs can be significantly reduced. Management of SBOs involves correction of physiologic and electrolyte disturbances, bowel rest and removing the source of the obstruction. Treatment of acute cyclic vomiting is primarily directed at symptom control, volume and electrolyte repletion, and appropriate specialist follow-up. The mainstay of therapy for gastroparesis is metoclopramide.

Prevalence of Small Intestinal Bacterial Overgrowth among Chronic Pancreatitis Patients: A Case-Control Study

Background. Patients with chronic pancreatitis (CP) exhibit numerous risk factors for the development of small intestinal bacterial overgrowth (SIBO). Objective. To determine the prevalence of SIBO in patients with CP. Methods. Prospective, single-centre case-control study conducted between January and September 2013. Inclusion criteria were age 18 to 75 years and clinical and radiological diagnosis of CP. Exclusion criteria included history of gastric, pancreatic, or intestinal surgery or significant clinical gastroparesis. SIBO was detected using a standard lactulose breath test (LBT). A healthy control group also underwent LBT. Results. Thirty-one patients and 40 controls were included. The patient group was significantly older (53.8 versus 38.7 years; P < 0.01). The proportion of positive LBTs was significantly higher in CP patients (38.7 versus 2.5%: P < 0.01). A trend toward a higher proportion of positive LBTs in women compared with men was observed (66.6 versus 27.3%; P = 0.056). The subgroups with positive and negative LBTs were comparable in demographic and clinical characteristics, use of opiates, pancreatic enzymes replacement therapy (PERT), and severity of symptoms. Conclusion. The prevalence of SIBO detected using LBT was high among patients with CP. There was no association between clinical features and the risk for SIBO.

Management of afferent loop obstruction: Reoperation or endoscopic and percutaneous interventions?

Afferent loop obstruction is a purely mechanical complication that infrequently occurs following construction of a gastrojejunostomy. The operations most commonly associated with this complication are gastrectomy with Billroth II or Roux-en-Y reconstruction, and pancreaticoduodenectomy with conventional loop or Roux-en-Y reconstruction. Etiology of afferent loop obstruction includes: (1) entrapment, compression and kinking by postoperative adhesions; (2) internal herniation, volvulus and intussusception; (3) stenosis due to ulceration at the gastrojejunostomy site and radiation enteritis of the afferent loop; (4) cancer recurrence; and (5) enteroliths, bezoars and foreign bodies. Acute afferent loop obstruction is associated with complete obstruction of the afferent loop and represents a surgical emergency, whereas chronic afferent loop obstruction is associated with partial obstruction. Abdominal multiple detector computed tomography is the diagnostic study of choice. CT appearance of the obstructed afferent loop consists of a C-shaped, fluid-filled tubular mass located in the midline between the abdominal aorta and the superior mesenteric artery with valvulae conniventes projecting into the lumen. The cornerstone of treatment is surgery. Surgery includes: (1) adhesiolysis and reconstruction for benign causes; and (2) by-pass or excision and reconstruction for malignant causes. However, endoscopic enteral stenting, transhepatic percutaneous enteral stenting and direct percutaneous tube enterostomy have the principal role in management of malignant and radiation-induced obstruction. Nevertheless, considerable limitations exist as a former Roux-en-Y reconstruction limits endoscopic access to the afferent loop and percutaneous approaches for enteral stenting and tube enterostomy have only been reported in the literature as isolated cases.

Effects of cigarette smoke condensate on the production and characterization of exopolysaccharides by Bifidobacterium

The aim of the study was to investigate the effect of cigarette smoke on the production and characterization of exopolysaccharides (EPSs) produced by Bifidobacterium. Cigarettes of Shanhua brand (nicotine: 1.1 mg, tar: 11 mg) were utilized to prepare a cigarette smoke condensate (CSC). The standard strain of Bifidobacterium animalis was cultured in MRS media under anaerobic addition of CSC. The results showed that CSC significantly decreased the growth of B. animalis as well as EPSs and acetic acid production. Furthermore, two EPSs fractions (Fr-I and Fr-II) were isolated and purified for chemical and molecular determination. By comparison with control, CSC was found to be of great impact on EPSs carbohydrate composition. The molecular weight mass of Fr-I changed from 3.33 × 10(5) g/mol (without CSC) to 2.99 × 10(5) (with CSC). In conclusion, in vitro studies revealed that CSC was directly able to affect the production of metabolites for B. animalis, which could be an essential factor in certain pathological disorders.

Clinical significance of the glucose breath test in patients with inflammatory bowel disease

BACKGROUND AND AIM

Small intestinal bacterial overgrowth which has recently been diagnosed with the glucose breath test is characterized by excessive colonic bacteria in the small bowel, and results in gastrointestinal symptoms that mimic symptoms of inflammatory bowel disease. This study aimed to estimate the positivity of the glucose breath test and investigate its clinical role in inflammatory bowel disease.

METHODS

Patients aged > 18 years with inflammatory bowel disease were enrolled. All patients completed symptom questionnaires. Fecal calprotectin level was measured to evaluate the disease activity. Thirty historical healthy controls were used to determine normal glucose breath test values.

RESULTS

A total of 107 patients, 64 with ulcerative colitis and 43 with Crohn's disease, were included. Twenty-two patients (20.6%) were positive for the glucose breath test (30.2%, Crohn's disease; 14.1%, ulcerative colitis). Positive rate of the glucose breath test was significantly higher in patients with Crohn's disease than in healthy controls (30.2% vs 6.7%, P=0.014). Bloating, flatus, and satiety were higher in glucose breath test-positive patients than glucose breath test-negative patients (P=0.021, 0.014, and 0.049, respectively). The positivity was not correlated with the fecal calprotectin level.

CONCLUSIONS

The positive rate of the glucose breath test was higher in patients with inflammatory bowel disease, especially Crohn's disease than in healthy controls; gastrointestinal symptoms of patients with inflammatory bowel disease were correlated with this positivity. Glucose breath test can be used to manage intestinal symptoms of patients with inflammatory bowel disease.

Thyroxine softgel capsule in patients with gastric-related T4 malabsorption

The key role of an intact gastric acid secretion for subsequent intestinal T4 absorption is supported by an increased requirement of thyroxine in patients with gastric disorders. A better pH-related dissolution profile has been described in vitro for softgel T4 preparation than for T4 tablets. Our study was aimed at comparing softgel and tablet T4 requirements in patients with gastric disorders. A total of 37 patients with gastric-related T4 malabsorption were enrolled, but only 31 (28F/3M; median age = 50 years; median T4 dose = 2.04 μg/kg/day) completed the study. All patients were in long-lasting treatment (>2 years) with the same dose of T4 tablets when treatment was switched to a lower dose of softgel T4 capsules (-17 %; p = 0.0002). Assessment of serum FT4 and TSH was carried out at baseline and after 3, 6, 12, and 18 months after the treatment switch. In more than 2/3 of patients (good-responders n = 21), despite the reduced dose of T4, median TSH values were similar at each time point (p = 0.3934) with no change in FT4 levels. In the remaining patients (poor-responders n = 10), TSH levels were significantly higher at each time point than at baseline (p < 0.0001). To note, in five of them intestinal comorbidity was subsequently detected. Comorbidity associated with poor-responders status was the only significant predictor in multivariate analysis (OR = 11.333). Doses of softgel T4 capsules lower than T4 tablet preparation are required to maintain the therapeutic goal in 2/3 of patients with impaired gastric acid secretion.

Predisposing factors for positive D-Xylose breath test for evaluation of small intestinal bacterial overgrowth: A retrospective study of 932 patients

AIM: To investigate, in the largest cohort to date, patient characteristics and associated risk factors for developing small intestinal bacterial overgrowth (SIBO) using the D-Xylose breath test (XBT).

METHODS: We performed a retrospective cross-sectional study to analyze patient characteristics who underwent the XBT for evaluation of SIBO. Diagnostic testing with the XBT was performed based on a clinical suspicion for SIBO in patients with symptoms of bloating, abdominal pain, abdominal distension, weight loss, diarrhea, and/or constipation. Consecutive electronic medical records of 932 patients who completed the XBT at the University of Florida between 2005 and 2009 were reviewed. A two-way Analysis of Variance (ANOVA) was used to test for several associations including age, gender, and body mass index (BMI) with a +XBT. A two-way ANOVA was also performed to control for the differences and interaction with age and between genders. A similar analysis was repeated for BMI. Associations between medical conditions and prior surgical histories were conducted using the Mantel-Haenszel method for 2 by 2 contingency tables, stratified for gender. Reported odds ratio estimates reflect the odds of the prevalence of a condition within the +XBT group to that of the -XBT group. P values of less than 0.05 (two-sided) were considered statistically significant.

RESULTS: In the 932 consecutive eligible subjects studied, 513 had a positive XBT. A positive association was found between female gender and a positive XBT (P = 0.0025), and females with a positive test were, on average, greater than 5 years older than those with a negative test (P = 0.024). The mean BMI of positive XBT subjects was normal (24.5) and significantly lower than the subjects with a negative XBT (29.5) (P = 0.0050). A positive XBT was associated with gastroesophageal reflux disease (GERD) (OR = 1.35; 95%CI: 1.02-1.80, P = 0.04), peptic ulcer disease (PUD) (OR = 2.61; 95%CI: 1.48-4.59, P < 0.01), gastroparesis (GP) (OR = 2.04; 95%CI: 1.21-3.41, P < 0.01) and steroid use (OR = 1.35; 95%CI: 1.02-1.80, P = 0.01). Irritable bowel syndrome, independent proton-pump inhibitor (PPI) usage, or previous abdominal surgery was not significantly associated with a positive XBT. No single subdivision by gender or PPI use was associated with a significant difference in the odds ratios between any of the subsets.

CONCLUSION: Female gender, lower BMI, steroid use, PUD, GERD (independent of PPI use), and GP were more prevalent in patients with SIBO, determined by a positive XBT. Increasing age was associated with SIBO in females, but not in males.

Breath testing for small intestinal bacterial overgrowth: maximizing test accuracy

The diagnosis of small intestinal bacterial overgrowth (SIBO) has increased considerably owing to a growing recognition of its association with common bowel symptoms including chronic diarrhea, bloating, abdominal distention, and the irritable bowel syndrome. Ideally, an accurate and objective diagnosis of SIBO should be established before initiating antibiotic treatment. Unfortunately, no perfect test exists for the diagnosis of SIBO. The current gold standard, small-bowel aspiration and quantitative culture, is limited by its high cost, invasive nature, lack of standardization, sampling error, and need for dedicated infrastructure. Although not without shortcomings, hydrogen breath testing provides the simplest noninvasive and widely available diagnostic modality for suspected SIBO. Carbohydrates such as lactulose and glucose are the most widely used substrates in hydrogen breath testing, with glucose arguably providing greater testing accuracy. Lactose, fructose, and sorbitol should not be used as substrates in the assessment of suspected SIBO. The measurement of methane in addition to hydrogen can increase the sensitivity of breath testing for SIBO. Diagnostic accuracy of hydrogen breath testing in SIBO can be maximized by careful patient selection for testing, proper test preparation, and standardization of test performance as well as test interpretation.

Abdominal wall defects: prenatal diagnosis, newborn management, and long-term outcomes

Omphalocele and gastroschisis represent the most frequent congenital abdominal wall defects a pediatric surgeon is called to treat. There has been an increased reported incidence in the past 10 years mainly due to the diffuse use of prenatal ultrasound. The early detection of these malformations, and related associated anomalies, allows a multidisciplinary counseling and planning of delivery in a center equipped with high-risk pregnancy assistance, pediatric surgery, and neonatology. At present times, closure of defects, even in multiple stages, is always possible as well as management of most of cardiac-, urinary-, and gastrointestinal-associated malformations. The progress, herein discussed, in the care of newborns with abdominal wall defects assures most of them survive and reach adulthood. Some aspects of transition of medical care will also be considered, including fertility and cosmesis.

Role of small intestinal bacterial overgrowth in severe small intestinal damage in chronic non-steroidal anti-inflammatory drug users

OBJECTIVE. Enteric bacteria play a significant role in the pathogenesis of non-steroidal anti-inflammatory drug (NSAID)-induced small intestinal damage. However, the association between small intestinal bacterial overgrowth (SIBO) and NSAID-induced small intestinal damage remains unclear. The aim of the study was to examine the association between SIBO and the presence of NSAID-induced severe small intestinal damage or its symptoms in chronic NSAID users. MATERIALS AND METHODS. Forty-three patients who had been using NSAIDs for over 3 months were enrolled. They were examined by capsule endoscopy and a lactulose hydrogen breath test (LHBT). We defined severe small intestinal damage as the presence of more than four small erosions or large erosions/ulcers. The LHBT result was considered positive if there was an increase in the level of breath hydrogen gas of >20 ppm above baseline. RESULTS. Out of 43 patients, 22 (51%) had severe small intestinal damage. The LHBT was positive in 5 of 21 patients (24%) without severe small intestinal damage and in 13 of 21 patients (59%) with severe small intestinal damage. Multiple logistic regression analysis showed that an LHBT-positive result was significantly associated with increased odds ratio for severe small intestinal damage (OR, 6.54; 95% CI, 1.40-30.50). There was no significant difference in the presence of symptoms between the LHBT-positive and LHBT-negative patients with severe small intestinal damage. CONCLUSION. SIBO might have a role in the development of severe small intestinal damage in chronic NSAID users.

Laparoscopy in the acute abdomen

Laparoscopy has become a routine procedure in the management of acute abdominal disease and can be considered both an excellent therapeutic and additional diagnostic tool in selected cases. However, a high level of expertise in laparoscopic and emergency surgery is required. Hemodynamic instability, huge abdominal distension, fecal peritonitis and perforated cancer are relative contraindications for the laparoscopic approach. In recent years, abdominal emergencies have increasingly been managed successfully by laparoscopy. In acute appendicitis, acute cholecystitis and perforated peptic ulcer, randomized controlled trials have proven that the laparoscopic approach is as safe and as effective as open surgery, with fewer complications and a quicker postoperative recovery. Other indications such as blunt and penetrating trauma to the abdomen, small bowel occlusion and perforated diverticular disease are under debate, indicating that more randomized controlled trials comparing laparoscopic and open surgery are still necessary.

Non-alcoholic fatty liver disease, diet and gut microbiota

Non-alcoholic fatty liver disease (NAFLD) is a severe liver disease that is increasing in prevalence with the worldwide epidemic of obesity and its related insulin-resistance state. Evidence for the role of the gut microbiota in energy storage and the subsequent development of obesity and some of its related diseases is now well established. More recently, a new role of gut microbiota has emerged in NAFLD. The gut microbiota is involved in gut permeability, low-grade inflammation and immune balance, it modulates dietary choline metabolism, regulates bile acid metabolism and produces endogenous ethanol. All of these factors are molecular mechanisms by which the microbiota can induce NAFLD or its progression toward overt non-alcoholic steatohepatitis. Modification of the gut microbiota composition and/or its biochemical capacity by specific dietary or pharmacological interventions may advantageously affect host metabolism. Large-scale intervention trials, investigating the potential benefit of prebiotics and probiotics in improving cardiometabolic health in high-risk populations, are fervently awaited.

Acute GI obstruction

Acute gastrointestinal obstruction occurs when the normal flow of intestinal contents is interrupted. The blockage can occur at any level throughout the gastrointestinal tract. The clinical symptoms depend on the level and extent of obstruction. Various benign and malignant processes can produce acute gastrointestinal obstruction, which often represents a medical emergency because of the potential for bowel ischemia leading to perforation and peritonitis. Early recognition and appropriate treatment are thus essential. The typical clinical symptoms associated with obstruction include nausea, vomiting, dysphagia, abdominal pain and failure to pass bowel movements. Abdominal distention, tympany due to an air-filled stomach and high-pitched bowel sounds suggest the diagnosis. The diagnostic process involves imaging including radiography, ultrasonography, contrast fluoroscopy and computer tomography in less certain cases. In patients with uncomplicated obstruction, management is conservative, including fluid resuscitation, electrolyte replacement, intestinal decompression and bowel rest. In many cases, endoscopy may aid in both the diagnostic process and in therapy. Endoscopy can be used for bowel decompression, dilation of strictures or placement of self-expandable metal stents to restore the luminal flow either as a final treatment or to allow for a delay until elective surgical therapy. When gastrointestinal obstruction results in ischemia, perforation or peritonitis, emergency surgery is required.

Proton pump inhibitor use and the risk of small intestinal bacterial overgrowth: a meta-analysis

BACKGROUND & AIMS

Use of proton pump inhibitors (PPIs) could predispose individuals to small intestinal bacterial overgrowth (SIBO) by altering the intraluminal environment and bacterial flora. There is controversy regarding the risk of SIBO among PPI users because of conflicting results from prior studies. A systematic review and meta-analysis were performed to evaluate the association between PPI use and SIBO, using objective clinical outcome measures.

METHODS

Clinical studies comparing SIBO risk among adult users of PPIs vs nonusers were identified in MEDLINE/PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, and the National Institutes of Health Clinical Trials databases through July 2012. Two reviewers independently extracted data on study characteristics and outcomes. The primary metameter was the odds ratio (OR) of SIBO among PPI users vs nonusers. Subgroup analyses were performed to examine the influence of study characteristics, such as SIBO diagnostic modality, on study outcome.

RESULTS

Eleven studies (n = 3134) met inclusion criteria. The pooled OR of SIBO in PPI users vs nonusers was 2.282 (95% confidence interval [CI], 1.238-4.205). No significant single large study or temporal effect was seen. Subgroup analysis revealed an association between SIBO and PPI use in studies that used duodenal or jejunal aspirate cultures to diagnose SIBO (OR, 7.587; 95% CI, 1.805-31.894), but no relationship was found between SIBO and PPI use in studies that used the glucose hydrogen breath test (OR, 1.93; 95% CI, 0.69-5.42). Funnel plot analysis identified 4 outlying studies, indicating the possible presence of publication bias.

CONCLUSIONS

PPI use statistically was associated with SIBO risk, but only when the diagnosis was made by a highly accurate test (duodenal or jejunal aspirate culture). Differences in study results could arise from the use of different tests to diagnose SIBO.

Delayed small intestinal transit in patients with long-standing type 1 diabetes mellitus: investigation of the relationships with clinical features, gastric emptying, psychological distress, and nutritional parameters

BACKGROUND

Studies on small intestinal transit in type 1 diabetes mellitus have reported contradictory results. This study assessed the orocecal transit time (OCTT) in a group of patients with type 1 diabetes mellitus and its relationships with gastrointestinal symptoms, glycemic control, chronic complications of diabetes, anthropometric indices, gastric emptying, small intestinal bacterial overgrowth (SIBO), and psychological distress.

SUBJECTS AND METHODS

Twenty-eight patients with long-standing (>10 years) type 1 diabetes mellitus (22 women, six men; mean age, 39 ± 9 years) participated in the study. The lactulose hydrogen breath test was used to determine OCTT and the occurrence of SIBO. The presence of anxiety and depression was assessed by the Hospital Anxiety and Depression scale. Gastric emptying was measured by scintigraphy. Anthropometric indices included body mass index, percentage body fat, midarm circumference, and arm muscle area.

RESULTS

There was a statistically significant increase in OCTT values in diabetes patients (79 ± 41 min) in comparison with controls (54 ± 17 min) (P=0.01). Individual analysis showed that OCTT was above the upper limit (mean+2 SD) in 30.8% of patients. All anthropometric parameters were significantly decreased (P<0.05) in patients with prolonged OCTT in comparison with those with normal OCTT. In contrast, there was no statistically significant association between prolonged OCTT and gastrointestinal symptoms, peripheral neuropathy, diabetic retinopathy, glycated hemoglobin, delayed gastric emptying, SIBO, anxiety, or depression.

CONCLUSIONS

Small bowel transit may be delayed in about one-third of patients with long-standing type 1 diabetes mellitus. This abnormality seems to have a negative effect on nutritional status in these patients.

Quantitative profiling of gut microbiota of children with diarrhea-predominant irritable bowel syndrome

OBJECTIVES

Human intestinal microbiota has a number of important roles in human health and is also implicated in several gastrointestinal disorders. The goal of this study was to determine the gut microbiota in two groups of pre- and adolescent children: healthy volunteers and children diagnosed with diarrhea predominant irritable bowel syndrome (IBS-D).

METHODS

Phylogenetic Microbiota Array was used to obtain quantitative measurements of bacterial presence and abundance in subjects ’ fecal samples. We utilized high-throughput DNA sequencing, quantitative PCR, and fluorescent in situ hybridization to confirm microarray findings.

RESULTS

Both sample groups were dominated by the phyla Firmicutes, Bacteroidetes, and Actinobacteria, which cumulatively constituted 91 % of overall sample composition on average. A core microbiome shared among analyzed samples encompassed 55 bacterial phylotypes dominated by genus Ruminococcus ; members of genera Clostridium , Faecalibacterium, Roseburia, Streptococcus , and Bacteroides were also present. Several genera were found to be differentially abundant in the gut of healthy and IBS groups: levels of Veillonella , Prevotella , Lactobacillus , and Parasporo bacterium were increased in children diagnosed with IBS, whereas members of Bifidobacterium and Verrucomicrobium were less abundant in those individuals. By calculating a nonparametric correlation matrix among abundances of different genera in all samples, we also examined potential associations among intestinal microbes. Strong positive correlations were found between abundances of Veillonella and both Haemophilus and Streptococcus , between Anaerovorax and Verrucomicrobium , and between Tannerella and Anaerophaga .

CONCLUSIONS

Although at the higher taxonomical level gut microbiota was similar between healthy and IBS-D children, specific differences in the abundances of several bacterial genera were revealed. Core microbiome in children was dominated by Clostridia. Putative relationships identified among microbial genera provide testable hypotheses of cross-species associations among members of human gut microbiota

[Proton-pump inhibitor therapy and small bowel bacterial contamination]

There are several causes of small bowel contamination. The effects of the long-term proton pump inhibitor treatment on the development of bowel symptoms and/or small intestinal bacterial overgrowth have been highlighted only in the past decade. The main diagnostic method is the hydrogen breath test that gives quantitative results with a simple, non-invasive procedure. There is a limited number of publications in the literature about the effects of proton pump inhibitor drugs on bowel bacterial milieau. Our results based on the investigations of two medical centres in Budapest show consistency with international data: the positive hydrogen breath test was present in 21% of the population using long-term proton pump inhibitors. In uncomplicated cases, symptom-free condition could be reached with probiotics, whereas in long lasting, chronic small intestinal bacterial overgrowth, antibiotic treatment should be considered. Rifaximin, a non-absorbable antibiotic showed high efficacy in the treatment of small intestinal bacterial overgrowth, with fewer side effects compared to systemic antibiotics.

Structural, functional and molecular analysis of the effects of aging in the small intestine and colon of C57BL/6J mice

BACKGROUND

By regulating digestion and absorption of nutrients and providing a barrier against the external environment the intestine provides a crucial contribution to the maintenance of health. To what extent aging-related changes in the intestinal system contribute to the functional decline associated with aging is still under debate.

METHODS

Young (4 M) and old (21 M) male C57BL/6J mice were fed a control low-fat (10E%) or a high-fat diet (45E%) for 2 weeks. During the intervention gross energy intake and energy excretion in the feces were measured. After sacrifice the small and large intestine were isolated and the small intestine was divided in three equal parts. Swiss rolls were prepared of each of the isolated segments for histological analysis and the luminal content was isolated to examine alterations in the microflora with 16S rRNA Q-PCR. Furthermore, mucosal scrapings were isolated from each segment to determine differential gene expression by microarray analysis and global DNA methylation by pyrosequencing.

RESULTS

Digestible energy intake was similar between the two age groups on both the control and the high-fat diet. Microarray analysis on RNA from intestinal scrapings showed no marked changes in expression of genes involved in metabolic processes. Decreased expression of Cubilin was observed in the intestine of 21-month-old mice, which might contribute to aging-induced vitamin B12 deficiency. Furthermore, microarray data analysis revealed enhanced expression of a large number of genes involved in immune response and inflammation in the colon, but not in the small intestine of the 21-month-old mice. Aging-induced global hypomethylation was observed in the colon and the distal part of the small intestine, but not in the first two sections of the small intestine.

CONCLUSION

In 21-month old mice the most pronounced effects of aging were observed in the colon, whereas very few changes were observed in the small intestine.

Lactulose hydrogen breath test and functional symptoms in pediatric patients

BACKGROUND

The role of small intestinal bacterial overgrowth (SIBO) in functional digestive disorders in the pediatric population is a matter of controversy, since methods currently used to establish this diagnosis are difficult to interpret. The aim of this work was to analyze the characteristics of the lactulose H(2) breath test (LHBT) in children with functional gastrointestinal symptoms according to more recent criteria.

METHODS

Seventy-two patients and 17 controls were enrolled. A questionnaire was administered regarding digestive symptoms (abdominal pain, bloating, vomiting, and bowel-movement disorders). A lactose hydrogen breath test was performed to rule out lactose malabsorption and a LHBT was used to measure the time elapsed between lactulose oral ingestion and an increment of H(2) concentration of 20 ppm over basal.

RESULTS

There were no differences of age and gender between patients and controls. Mean time to 20-ppm change was shorter in patients (56.3 ± 3 min) compared to healthy children (74.7 ± 5 min), p\0.05. In 39% of patients, rise of H(2) occurred during the first 40 min after lactulose ingestion, and in almost all controls, an increment was observed between 50 and 90 min (p\0.05). Symptoms were unrelated to time to 20-ppm change.

CONCLUSIONS

An abnormal LHBT was found in children with functional symptoms of the digestive tract, but the exact mechanism involved, accelerated intestinal transit or SIBO, needs to be confirmed by an additional method.

Effect of antibiotic treatment on fat absorption in mice with cystic fibrosis

INTRODUCTION

Improving fat absorption remains a challenge in cystic fibrosis (CF). Antibiotics (AB) treatment has been shown to improve body weight in CF mice. The mechanism may include improvement in fat absorption. We aimed to determine the effect of AB on fat absorption in two CF mouse models.

RESULTS

AB did not improve total fat absorption. Interestingly, AB accelerated the absorption of isotope-labeled fats, in both Δ/Δ and WT mice. The changes observed were not related to the solubilization capacity of bile or to changes in the bacteria in the small intestine. AB reduced the fecal excretion of cholate by ~50% (P < 0.05) in both CF mouse models, indicating improved intestinal bile salt absorption.

DISCUSSION

In conclusion, AB treatment does not improve total fat absorption in CF mice but does decrease fecal loss of bile salts and accelerate long-chain fatty acid (LCFA) absorption.

METHODS

For 3 weeks, we administered oral AB (ciprofloxacin/metronidazole) or control treatment to homozygous ΔF508 (Δ/Δ), cystic fibrosis transmembrane conductance regulator (CFTR) knockout (-/-), and wild-type (WT) mice and quantified fat absorption using a 72-h fat balance test. In Δ/Δ mice, we assessed fat absorption kinetics by administering tri-1-(13)C-palmitin and 1-(13)C-stearate intragastrically and determining the appearance of stable isotope-labeled fats in plasma. We quantified biliary and fecal bile salts (gas chromatography) and small intestinal bacteria (quantitative-PCR).

A review of rifaximin and bacterial overgrowth in poorly responsive celiac disease

A proportion of patients with celiac disease have a poor response to a gluten-free diet, which may be due to small-intestinal bacterial overgrowth (SIBO). Treatment with rifaximin is often used in the clinical setting, but there is limited literature to support this practice. In addition, challenges in the diagnosis of SIBO confound response interpretation. Our recent placebo-controlled trial did not demonstrate any improvement in gastrointestinal symptoms after treatment with rifaximin and casts doubt on the utility of lactulose-hydrogen breath testing for SIBO in this population.

Orocecal transit time and small intestinal bacterial overgrowth in type 2 diabetes patients from North India

BACKGROUND

Diarrhea, constipation, flatulence, and abdominal pain are common complaints in type 2 diabetes patients. Impaired intestinal motility is often followed by small intestinal bacterial overgrowth (SIBO). Therefore, this study was planned to determine the incidence of SIBO and its relation with orocecal transit time (OCTT) in type 2 diabetes patients.

SUBJECTS AND METHODS

SIBO and OCTT were measured by using noninvasive glucose and lactulose hydrogen breath tests, respectively. For this study, 84 patients with type 2 diabetes mellitus in the age range 30-65 years and 45 age-matched apparently healthy controls were enrolled.

RESULTS

The glucose hydrogen breath test was suggestive of SIBO in 15.5% of patients with type 2 diabetes mellitus but in one (2.2%) of controls. There was a significant increase (P<0.001) in OCTT in type 2 diabetes patients compared with controls. It was also observed that OCTT in type 2 diabetes patients with SIBO was significantly delayed (P<0.001) compared with type 2 diabetes patients without SIBO.

CONCLUSION

This study indicates that SIBO in diabetes patients may be due to delayed OCTT.

Double-blind randomized controlled trial of rifaximin for persistent symptoms in patients with celiac disease

BACKGROUND

Small intestinal bacterial overgrowth (SIBO) is one cause of a poor response to a gluten-free diet (GFD) and persistent symptoms in celiac disease. Rifaximin has been reported to improve symptoms in non-controlled trials.

AIMS

To determine the effect of rifaximin on gastrointestinal symptoms and lactulose-hydrogen breath tests in patients with poorly responsive celiac disease.

METHODS

A single-center, double-blind, randomized, controlled trial of patients with biopsy-proven celiac disease and persistent gastrointestinal symptoms despite a GFD was conducted. Patients were randomized to placebo (n = 25) or rifaximin (n = 25) 1,200 mg daily for 10 days. They completed the Gastrointestinal Symptom Rating Scale (GSRS) and underwent lactulose-hydrogen breath tests at weeks 0, 2, and 12. An abnormal breath test was defined as: (1) a rise in hydrogen of ≥20 parts per million (ppm) within 100 min, or (2) two peaks ≥20 ppm over baseline.

RESULTS

GSRS scores were unaffected by treatment with rifaximin, regardless of baseline breath tests. In a multivariable regression model, the duration of patients' gastrointestinal symptoms significantly predicted their overall GSRS scores (estimate 0.029, p < 0.006). According to criteria 1 and 2, respectively, SIBO was present in 55 and 8% of patients at baseline, intermittently present in 28 and 20% given placebo, and 28 and 12% given rifaximin. There was no difference in the prevalence of SIBO between placebo and treatment groups at weeks 2 and 12.

CONCLUSIONS

Rifaximin does not improve patients' reporting of gastrointestinal symptoms and hydrogen breath tests do not reliably identify who will respond to antibiotic therapy.

Gastrointestinal complaints in runners are not due to small intestinal bacterial overgrowth

Background

Gastrointestinal complaints are common among long distance runners. We hypothesised that small intestinal bacterial overgrowth (SIBO) is present in long distance runners frequently afflicted with gastrointestinal complaints.

Findings

Seven long distance runners (5 female, mean age 29.1 years) with gastrointestinal complaints during and immediately after exercise without known gastrointestinal diseases performed Glucose hydrogen breath tests for detection of SIBO one week after a lactose hydrogen breath test checking for lactose intolerance. The most frequent symptoms were diarrhea (5/7, 71%) and flatulence (6/7, 86%). The study was conducted at a laboratory.

In none of the subjects a pathological hydrogen production was observed after the intake of glucose. Only in one athlete a pathological hydrogen production was measured after the intake of lactose suggesting lactose intolerance.

Conclusions

Gastrointestinal disorders in the examined long distance runners were not associated with small intestinal bacterial overgrowth.

Clinical predictors of small intestinal bacterial overgrowth by duodenal aspirate culture

BACKGROUND

There has been increasing interest in small intestinal bacterial overgrowth (SIBO) after reports of a link with irritable bowel syndrome (IBS), yet our understanding of this entity is limited.

AIM

Our aim was to estimate the yield of patients undergoing duodenal aspirate culture, and to identify symptoms and features that predict SIBO.

METHODS

A medical chart review of patients who had undergone duodenal aspirate culture at an academic medical centre in 2003 was performed to record clinical characteristics and culture results. The associations between aspirate results and symptoms, medical diagnoses and medication use were assessed using logistic regression.

RESULTS

A total of 675 patients had available aspirate results. Mean age of the sample was 53 (s.d. 17) and 443 (66%) were female patients. Overall, 8% of aspirates were positive for SIBO; 2% of IBS patients had SIBO. Older age, steatorrhoea and narcotic use were associated with SIBO (P < 0.05). PPI use was not associated with SIBO, but was associated with bacterial growth not meeting criteria for SIBO (P < 0.05). Inflammatory bowel disease (IBD), small bowel diverticula and pancreatitis were positively associated with an abnormal duodenal aspirate (P < 0.05), but other conditions including IBS were not associated with SIBO.

CONCLUSION

Older age, steatorrhoea, narcotic use, IBD, small bowel diverticula and pancreatitis were associated with small intestinal bacterial overgrowth based on abnormal duodenal aspirate culture results. However, no clear associations of true small intestinal bacterial overgrowth with IBS or PPI use were detected, in contrast to recent speculation.

Diagnosis and pharmacological management of small intestinal bacterial overgrowth in children with intestinal failure

The present article provides a general overview of the possible diagnostic procedures available for the management of small intestinal bacterial overgrowth in pediatric patients with intestinal failure. The focus is to address current diagnostic tools and understand their associated advantages and disadvantages based on a literature search. Culture of small intestinal aspirates, noninvasive breath tests and an emerging interest in quantitative bacterial DNA fingerprinting are discussed. Proper management is critical for preventing the recurrence of small intestinal bacterial overgrowth and its related complications. Antibiotic prophylaxis is one approach to the treatment of bacterial overgrowth in intestinal failure patients. Although treatment trials can be challenging in such a vulnerable population, more investigative clinical studies examining early diagnosis, more effective control of recurrence and the prevention of associated complications must be conducted.

Small intestinal bacterial overgrowth

Despite the current increase in interest in the role of the microbiota in health and disease and the recognition, for over 50 years, that an excess of colonic-type flora in the small intestine could lead to a malabsorption syndrome, small intestinal overgrowth remains poorly defined. This lack of clarity owes much to the difficulties that arise in attempting to arrive at consensus with regard to the diagnosis of this condition: there is currently no gold standard and the commonly available methodologies (the culture of jejunal aspirates and a variety of breath tests) suffer from considerable variations in their performance and interpretation, leading to variations in the prevalence of overgrowth in a variety of clinical contexts. Treatment is similarly supported by a scant evidence base and the most commonly used antibiotic regimens owe more to custom than clinical trials.

Endoscopic jejunal biopsy culture: a simple and effective method to study jejunal microflora

BACKGROUND

Jejunal fluid culture is the gold standard for assessing jejunal microflora. Aspiration of jejunal fluid is sometime difficult. As the microorganisms rests on the mucosal surface, culture of the mucosal biopsy may be a possible alternative method.

AIM

To study the role of jejunal mucosal biopsy culture to assess jejunal microflora and to compare it with jejunal fluid culture.

METHODS

Thirty adult subjects with gastroesophageal reflux disease requiring endoscopy underwent enteroscopy. Jejunal fluid aspirate and mucosal biopsy were cultured. The procedure was repeated after omeprazole therapy in 18 patients.

RESULTS

Forty-eight pairs (30 preomeprazole therapy and 18 postomeprazole therapy) of fluid and mucosal biopsies were cultured. In 45 of the 48 pairs (94%), both the culture of jejunal biopsy and jejunal fluid yielded similar results with respect to the presence (n = 27) or absence of growth (n = 18). In the remaining 3 pairs, the growth was present either in the biopsy culture (n = 2) or in the fluid culture (n = 1) only. Among those pairs in which growth was present, microorganisms isolated were identical in 53%, differed by ≤ 2 organism in 37% and different by >2 organisms in 10%. Ten of the 12 patients who were detected to have small intestinal bacterial overgrowth (SIBO) on fluid culture were also detected to have SIBO on biopsy culture. Sensitivity, specificity, positive and negative predictive value of biopsy culture in diagnosing SIBO was 83.5%, 97.2%, 94.7%, and 91.6%, respectively.

CONCLUSION

Culture of unwashed endoscopic jejunal mucosal biopsy is an effective and simple alternative to jejunal fluid culture for assessing jejunal microflora.