Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients

In this editorial,we discuss the article in the World Journal of Gastroenterology.The article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(H.pylori)infection in humans.It is based on radionuclide-labeled urea.Various methods,both invasive and non-invasive,are available for diagnosing H.pylori infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and UBT.Several guidelines recommend UBTs as the primary choice for diagnosing H.pylori infection and for reexamining after eradication therapy.It is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and simplicity.Moreover,its performance remains unaffected by the distribution of H.pylori in the stomach,allowing a high flow of patients to be tested.Despite its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely defined.There are two UBTs available with Food and Drug Administration approval:The 13C and 14C tests.Both tests are affordable and can provide real-time results.Physicians may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant women.Although there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the 14C-UBT.This makes the 13C-UBT the preferred diagnostic approach.Furthermore,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision.

Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy

BACKGROUND Helicobacter pylori(H.pylori)infection has been well-established as a significant risk factor for several gastrointestinal disorders.The urea breath test(UBT)has emerged as a leading non-invasive method for detecting H.pylori.Despite numerous studies confirming its substantial accuracy,the reliability of UBT results is often compromised by inherent limitations.These findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of H.pylori infection.AIM To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for H.pylori infection in adult patients with dyspepsia.METHODS We conducted an independent search of the PubMed/MEDLINE,EMBASE,and Cochrane Central databases until April 2022.Our search included diagnostic accuracy studies that evaluated at least one of the index tests(^(13)C-UBT or ^(14)C-UBT)against a reference standard.We used the QUADAS-2 tool to assess the methodo-logical quality of the studies.We utilized the bivariate random-effects model to calculate sensitivity,specificity,positive and negative test likelihood ratios(LR+and LR-),as well as the diagnostic odds ratio(DOR),and their 95%confidence intervals.We conducted subgroup analyses based on urea dosing,time after urea administration,and assessment technique.To investigate a possible threshold effect,we conducted Spearman correlation analysis,and we generated summary receiver operating characteristic(SROC)curves to assess heterogeneity.Finally,we visually inspected a funnel plot and used Egger’s test to evaluate publication bias.endorsing both as reliable diagnostic tools in clinical practice.CONCLUSION In summary,our study has demonstrated that ^(13)C-UBT has been found to outperform the ^(14)C-UBT,making it the preferred diagnostic approach.Additionally,our results emphasize the significance of carefully considering urea dosage,assessment timing,and measurement techniques for both tests to enhance diagnostic precision.Nevertheless,it is crucial for researchers and clinicians to evaluate the strengths and limitations of our findings before implementing them in practice.

Ability of lactulose breath test results to accurately identify colorectal polyps through the measurement of small intestine bacterial overgrowth

BACKGROUND While colorectal polyps are not cancerous,some types of polyps,known as adenomas,can develop into colorectal cancer over time.Polyps can often be found and removed by colonoscopy;however,this is an invasive and expensive test.Thus,there is a need for new methods of screening patients at high risk of developing polyps.AIM To identify a potential association between colorectal polyps and small intestine bacteria overgrowth(SIBO)or other relevant factors in a patient cohort with lactulose breath test(LBT)results.METHODS A total of 382 patients who had received an LBT were classified into polyp and non-polyp groups that were confirmed by colonoscopy and pathology.SIBO was diagnosed by measuring LBTderived hydrogen(H)and methane(M)levels according to 2017 North American Consensus recommendations.Logistic regression was used to assess the ability of LBT to predict colorectal polyps.Intestinal barrier function damage(IBFD)was determined by blood assays.RESULTS H and M levels revealed that the prevalence of SIBO was significantly higher in the polyp group than in the non-polyp group(41%vs 23%,P<0.01;71%vs 59%,P<0.05,respectively).Within 90 min of lactulose ingestion,the peak H values in the adenomatous and inflammatory/hyperplastic polyp patients were significantly higher than those in the non-polyp group(P<0.01,and P=0.03,respectively).In 227 patients with SIBO defined by combining H and M values,the rate of IBFD determined by blood lipopolysaccharide levels was significantly higher among patients with polyps than those without(15%vs 5%,P<0.05).In regression analysis with age and gender adjustment,colorectal polyps were most accurately predicted with models using M peak values or combined H and M values limited by North American Consensus recommendations for SIBO.These models had a sensitivity of≥0.67,a specificity of≥0.64,and an accuracy of≥0.66.CONCLUSION The current study made key associations among colorectal polyps,SIBO,and IBFD and demonstrated that LBT has moderate potential as an alternative noninvasive screening tool for colorectal polyps.

Effects of ethanol and sex on propionate metabolism evaluated via a faster ^(13)C-propionate breath test in rats

BACKGROUND Alcoholism is regarded as a risk factor for vitamin B_(12)(VB_(12))deficiency.Because V B_(12) serves as a coenzyme of methylmalonyl-CoA mutase,a key enzyme in propionate metabolism,the ^(13)C-propionate breath test(PBT)has been studied as a non-invasive diagnostic modality for VB_(12) deficiency.However,the conventional PBT requires 2 h,which is inconvenient in clinical practice.We hypothesized that a faster PBT can be used to evaluate propionate metabolism and is more easily adaptable for clinical practice.AIM To evaluate a faster PBT for assessing the effects of long-term ethanol consumption on propionate metabolism in ethanol-fed rats(ERs).METHODS ERs were obtained by replacing standard drinking water(for control rats,CRs)with 16%ethanol solution in descendants of F344/DuCrj rats.Faster PBT was performed by administering ^(13)C-propionate aqueous solution to male and female ERs and CRs by inserting a metal tubule from the mouth to the stomach;exhaled gas was collected in a bag to measure its ^(13)CO_(2)/12CO_(2) isotope ratio via infrared isotope spectrometry.Serum VB_(12) and alanine transaminase(ALT)levels were measured via chemiluminescence immunoassay and the lactate dehydrogenaseultraviolet method,respectively.We evaluated statistical differences in mean body weight,change in ^(13)CO_(2)(Δ^(13)CO_(2)‰),peakΔ^(13)CO_(2)‰,and serum VB_(12) and ALT,between males and females and between ERs and CRs using the t-test and Mann-Whitney U test for normally and non-normally distributed variables,respectively.RESULTS Males weighed significantly more than females(P<0.001);CRs weighed significantly more than ERs(P<0.008).Δ^(13)CO_(2) reached a peak(C_(max))at 20 min and 30 min in females and males,respectively,decreasing after 20-30 min without rebound in all groups.Males had significantly higher C_(max) andΔ^(13)CO_(2) at 15-45 min than females(P<0.05;for all pairs).Propionate metabolism was enhanced in male ERs relative to male CRs,whereas metabolism did not differ markedly between ERs and CRs for females.Males had higher serum VB_(12) levels than females,without prominent differences between the ER and CR groups.Male CRs had notably higher ALT levels than male ERs.Thus,chronic ethanol consumption may trigger fatty acid production via intestinal bacteria and changes in gut microbiome composition.CONCLUSION Faster PBT shows that 16%ethanol consumption promotes propionate metabolism without inducing liver injury.This PBT may be used clinically to evaluate gut flora status.

Modified Helicobacter test using a new test meal and a 13C-urea breath test in Helicobacter pylori positive and negative dyspepsia patients on proton pump inhibitors

AIM To determine the sensitivity and specificity of the ^(13)C-urea breath test(UBT) in patients taking proton pump inhibitors(PPIs), using a new test meal Refex. METHODS One hundred and fourteen consecutive patients with dyspepsia, 53 Helicobacter pylori(H. pylori) positive, 49 H. pylori negative, were included in the study. The patients were then given esomeprazole 40 mg for 29 consecutive days, and the ^(13)C-UBT with the new test meal was performed the next morning. RESULTS The sensitivity of the ^(13)C-UBT with a cut off 2.5‰ was92.45%(95%CI: 81.79%-97.91%) by per-protocol(PP) analysis and 78.13 %(95%CI: 66.03%-87.49%) by intention-to-treat(ITT) analysis. The specificity of the ^(13)C-UBT test was 96.00 % in the ITT population(95%CI: 86.29%-99.51%) and 97.96% in the PP population(95%CI: 89.15%-99.95%).CONCLUSION The new test meal based ^(13)C-UBT is highly accurate in patients on PPIs and can be used in those unable to stop their PPI treatment.

Glucose substrate in the hydrogen breath test for gut microbiota determination:A recommended noninvasive test

Intestinal dysbiosis and small intestinal bacterial overgrowth(SIBO)are common in patients with liver cirrhosis.Existing studies have not explored the association between gut dysbiosis and SIBO.We propose some suggestions for the authors’experimental methods and concepts,and we hope these suggestions can be adopted.The hydrogen breath test is worthy of recommendation due to its high accuracy and convenient operation.We suggest changing the substrate of the hydrogen breath test from lactulose to glucose to improve the accuracy of each parameter.SIBO is a small subset of gut dysbiosis,and we propose clarifying the concept of both.SIBO may be caused by liver cirrhosis or one of the pathogeneses of gastrointestinal diseases.Therefore,interference from other gastrointestinal diseases should be excluded from this study.

13C Protein Oxidation in Breath: Is It Relevant for the Whole Body Protein Status?

Introduction: The kinetics of protein oxidation, monitored in breath, and its contribution to the whole body protein status is not well established. Objectives: To analyze protein oxidation in various metabolic conditions we developed/validated a 13C-protein oxidation breath test using low enriched milk proteins. Method/Design: 30 g of naturally labeled 13C-milk proteins were consumed by young healthy volunteers. Breath samples were taken every 10 min and 13CO2 was measured by Isotope Ratio Mass Spectrometry. To calculate the amount of oxidized substrate we used: substrate dose, molecular weight and 13C enrichment of the substrate, number of carbon atoms in a substrate molecule, and estimated CO2-production of the subject based on body surface area. Results: We demonstrated that in 255 min 20% ± 3% (mean ± SD) of the milk protein was oxidized compared to 18% ± 1% of 30 g glucose. Postprandial kinetics of oxidation of whey (rapidly digestible protein) and casein (slowly digestible protein) derived from our breath test were comparable to literature data regarding the kinetics of appearance of amino acids in blood. Oxidation of milk proteins was faster than that of milk lipids (peak oxidation 120 and 290 minutes, respectively). After a 3-day protein restricted diet (~10 g of protein/day) a decrease of 31% ± 18% in milk protein oxidation was observed compared to a normal diet. Conclusions: Protein oxidation, which can be easily monitored in breath, is a significant factor in protein metabolism. With our technique we are able to characterize changes in overall protein oxidation under various meta-bolic conditions such as a protein restricted diet, which could be relevant for defining optimal protein intake under various conditions. Measuring protein oxidation in new-born might be relevant to establish its contribution to the protein status and its age-dependent development.

Epidemiology of small intestinal bacterial overgrowth

Small intestinal bacterial overgrowth(SIBO)is defined as an increase in the bacterial content of the small intestine above normal values.The presence of SIBO is detected in 33.8%of patients with gastroenterological complaints who underwent a breath test,and is significantly associated with smoking,bloating,abdominal pain,and anemia.Proton pump inhibitor therapy is a significant risk factor for SIBO.The risk of SIBO increases with age and does not depend on gender or race.SIBO complicates the course of a number of diseases and may be of pathogenetic significance in the development of their symptoms.SIBO is significantly associated with functional dyspepsia,irritable bowel syndrome,functional abdominal bloating,functional constipation,functional diarrhea,short bowel syndrome,chronic intestinal pseudo-obstruction,lactase deficiency,diverticular and celiac diseases,ulcerative colitis,Crohn’s disease,cirrhosis,metabolic-associated fatty liver disease(MAFLD),primary biliary cholangitis,gastroparesis,pancreatitis,cystic fibrosis,gallstone disease,diabetes,hypothyroidism,hyperlipidemia,acromegaly,multiple sclerosis,autism,Parkinson’s disease,systemic sclerosis,spondylarthropathy,fibromyalgia,asthma,heart failure,and other diseases.The development of SIBO is often associated with a slowdown in orocecal transit time that decreases the normal clearance of bacteria from the small intestine.The slowdown of this transit may be due to motor dysfunction of the intestine in diseases of the gut,autonomic diabetic polyneuropathy,and portal hypertension,or a decrease in the motor-stimulating influence of thyroid hormones.In a number of diseases,including cirrhosis,MAFLD,diabetes,and pancreatitis,an association was found between disease severity and the presence of SIBO.Further work on the effect of SIBO eradication on the condition and prognosis of patients with various diseases is required.

Helicobacter pylori infection in Xinjiang Uyghur Autonomous Region:Prevalence and analysis of related factors

BACKGROUND^(14)C urea breath test(^(14)C UBT)and immunohistochemical staining(IHC)are widely used for detection Helicobacter pylori(H.pylori)infection with different sensitivity,and there is a difference in H.pylori infection rate in Uyghur and Han ethnic groups.Both need large cohort studies to evaluate the differences more accurately.AIM To analyze the difference between^(14)C UBT and IHC for H.pylori detection in Xinjiang Uyghur Autonomous Region and the difference between Uyghur and Han populations.METHODS There were 3944 cases of H.pylori infection detected by both IHC and^(14)C UBT at the same time(interval<1 wk,with sampling site including gastric antrum,selected from 5747 patients).We compared the sensitivity of^(14)C UBT and IHC.We also compared 555 pairs of Han/Uyghur cases(completely matched for gender and age)for their H.pylori infection rates.The overall H.pylori infection rate of all 5747 cases and the correlation with other clinicopathological data were also further analyzed.SPSS V23.0 software was used for statistical analysis.RESULTS The sensitivity was 94.9%for^(14)C UBT and 65.1%for IHC,which was a significant difference(n=3944,P<0.001).However,among those cases negative for H.pylori by^(14)C UBT(detection value≤100),4.8%were positive by IHC.Combining both methods,the overall H.pylori infection rate was 48.6%(n=5747),and differences in gender,age group,ethnicity and region of residence significantly affected the H.pylori positive rates.According to age group(Han/Uyghur),the positive rates were≤30 years(62.2%/100.0%),31-40 years(45.2%/85.7%),41-50 years(47.2%/79.2%),51-60 years(44.6%/76.1%),61-70 years(40.9%/68.2%),71-80 years(41.7%/54.1%)and≥81 years(42.9%/NA).The H.pylori infection rates of Han/Uyghur paired cases were 41.4%and 73.3%,which was a significant difference(P<0.001)(555 pairs).H.pylori positivity was significantly related to moderate-severe grade 2-3 chronic/active gastritis and intestinal metaplasia(all P<0.05).CONCLUSION The sensitivity of^(14)C UBT was significantly higher,but combined application can still increase the accuracy.The prevention H.pylori should be emphasized for Uygur and young people.

Progress in Diagnosis and Treatment of Small Intestinal Bacterial Overgrowth

Small intestinal bacterial overgrowth has been found to be associated with a variety of gastrointestinal disorders such as irritable bowel syndrome, inflammatory bowel disease, and, in recent years, diabetes mellitus and systemic sclerosis, among other extraintestinal diseases. Several novel diagnostic tools for small intestinal bacterial overgrowth have emerged in recent years, and several therapeutic approaches have been proposed. Therefore, it has become necessary to find an effective, safe, and simple diagnostic method and a safe treatment modality. This article provides a review of current diagnostic and therapeutic approaches to small intestinal bacterial overgrowth.

Gastroparesis:New insights into an old disease

Gastroparesis(Gp)is a chronic disease characterized by a delayed gastric emptying in the absence of mechanical obstruction.Although this condition has been reported in the literature since the mid-1900s,only recently has there been renewed clinical and scientific interest in this disease,which has a potentially great impact on the quality of life.The aim of this review is to explore the pathophysiological,diagnostic and therapeutical aspects of Gp according to the most recent evidence.A comprehensive online search for Gp was carried out using MEDLINE and EMBASE.Gp is the result of neuromuscular abnormalities of the gastric motor function.There is evidence that patients with idiopathic and diabetic Gp may display a reduction in nitrergic inhibitory neurons and in interstitial cells of Cajal and/or telocytes.As regards diagnostic approach,99-Technetium scintigraphy is currently considered to be the gold standard for Gp.Its limits are a lack of standardization and a mild risk of radiation exposure.The C13 breath testing is a valid and safe alternative method.13C acid octanoic and the 13C Spirulina platensis recently approved by the Food and Drug Administration are the most commonly used diagnostic kits.The wireless motility capsule is a promising technique,but its use is limited by costs and scarce availability in many countries.Finally,therapeutic strategies are related to the clinical severity of Gp.In mild and moderate Gp,dietary modification and prokinetic agents are generally sufficient.Metoclopramide is the only drug approved by the Food and Drug Administration for Gp.However,other older and new prokinetics and antiemetics can be considered.As a second-line therapy,tricyclic antidepressants and cannabinoids have been proposed.In severe cases the normal nutritional approach can be compromised and artificial nutrition may be needed.In drug-unresponsive Gp patients some alternative strategies(endoscopic,electric stimulation or surgery)are available.

Small intestinal bacterial overgrowth syndrome

Human intestinal microbiota create a complex polymi-crobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO).SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastro-intestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacte-riostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insuff iciency, immuno-deficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, f istulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Noninvasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be com-plex, addressing all causes, symptoms and complica-tions, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO.

Epidemiological investigation of Helicobacter pylori infection in elderly people in Beijing

BACKGROUND The Helicobacter pylori(H.pylori)infection rate in China is approximately 50%.H.pylori is a pathogenic factor of peptic ulcer and chronic gastritis.In addition,H.pylori infection may also be associated with a variety of cardiovascular diseases in elderly people,such as arteriosclerosis,coronary heart disease,and cerebral infarction,having deleterious effect on their health.With the aging of the population,the disease characteristics of the elderly population have been increasingly valued by the whole society.We conducted an epidemiological survey of H.pylori infection among elderly people in Beijing to provide a basis for health management of H.pylori infection.AIM To understand the epidemiological characteristics of H.pylori infection in elderly people in Beijing.METHODS A total of 1090 elderly people aged more than 60 years from different parts of Beijing(urban and rural areas)were selected using the random cluster sampling method.Structured questionnaires were completed during home visits and the 13C-urea breath test was conducted for H.pylori detection.RESULTS The prevalence of H.pylori infection was 46.5%(507/1090).The infection rate in men was 51.8%,which was significantly higher than that in women(42.5%;P<0.05).The H.pylori infection rate in illiterate people was significantly higher than that in literate persons(53.5%vs 44.8%,P<0.05).The total infection rate of H.pylori gradually increased with age and the difference was statistically significant(P<0.01).The H.pylori infection rate in smokers was significantly higher than that in non-smokers and those who had quit smoking(P<0.05).CONCLUSION The prevalence of H.pylori infection among elderly people is 46.5%and the infection rate gradually increases with age.Sex,education level,age,and smoking were determined to be H.pylori infection risk factors.The relationship of H.pylori infection with region,occupation,drinking,and diet structure needs to be further studied.

Intestinal bacterial overgrowth in the early stage of severe acute pancreatitis is associated with acute respiratory distress syndrome

BACKGROUND In the early stage of acute pancreatitis(AP),a large number of cytokines induced by local pancreatic inflammation seriously damage the intestinal barrier function,and intestinal bacteria and endotoxins enter the blood,causing inflammatory storm,resulting in multiple organ failure,infectious complications,and other disorders,eventually leading to death.Intestinal failure occurs early in the course of AP,accelerating its development.As an alternative method to detect small intestinal bacterial overgrowth,the hydrogen breath test is safe,noninvasive,and convenient,reflecting the number of intestinal bacteria in AP indirectly.This study aimed to investigate the changes in intestinal bacteria measured using the hydrogen breath test in the early stage of AP to clarify the relationship between intestinal bacteria and acute lung injury(ALI)/acute respiratory distress syndrome(ARDS).Early clinical intervention and maintenance of intestinal barrier function would be highly beneficial in controlling the development of severe acute pancreatitis(SAP).AIM To analyze the relationship between intestinal bacteria change and ALI/ARDS in the early stage of SAP.METHODS A total of 149 patients with AP admitted to the intensive care unit of the Digestive Department,Xuanwu Hospital,Capital Medical University from 2016 to 2019 were finally enrolled,following compliance with the inclusion and exclusion criteria.The results of the hydrogen breath test within 1 wk of admission were collected,and the hydrogen production rates at admission,72 h,and 96 h were calculated.The higher the hydrogen production rates the more bacteria in the small intestine.First,according to the improved Marshall scoring system in the 2012 Atlanta Consensus on New Standards for Classification of Acute Pancreatitis,66 patients with a PaO2/FiO2 score≤1 were included in the mild AP(MAP)group,18 patients with a PaO2/FiO2 score≥2 and duration<48 h were included in the moderately SAP(MSAP)group,and 65 patients with a PaO2/FiO2 score≥2 and duration>48 h were included in the SAP group,to analyze the correlation between intestinal bacterial overgrowth and organ failure in AP.Second,ALI(PaO2/FiO2=2)and ARDS(PaO2/FiO2>2)were defined according to the simplified diagnostic criteria proposed by the 1994 European Union Conference.The MSAP group was divided into two groups according to the PaO2/FiO2 score:15 patients with PaO2/FiO2 score=2 were included in group A,and three patients with score>2 were included in group B.Similarly,the SAP group was divided into two groups:28 patients with score=2 were included in group C,and 37 patients with score>2 were included in group D,to analyze the correlation between intestinal bacterial overgrowth and ALI/ARDS in AP.RESULTS A total of 149 patients were included:66 patients in the MAP group,of whom 53 patients were male(80.3%)and 13 patients were female(19.7%);18 patients in the MSAP group,of whom 13 patients were male(72.2%)and 5 patients were female(27.8%);65 patients in the SAP group,of whom 48 patients were male(73.8%)and 17 patients were female(26.2%).There was no significant difference in interleukin-6 and procalcitonin among the MAP,MSAP,and SAP groups(P=0.445 and P=0.399,respectively).There was no significant difference in the growth of intestinal bacteria among the MAP,MSAP,and SAP groups(P=0.649).There was no significant difference in the growth of small intestinal bacteria between group A and group B(P=0.353).There was a significant difference in the growth of small intestinal bacteria between group C and group D(P=0.038).CONCLUSION Intestinal bacterial overgrowth in the early stage of SAP is correlated with ARDS.

Levothyroxine therapy and impaired clearance are the strongest contributors to small intestinal bacterial overgrowth: Results of a retrospective cohort study

AIM To identify a set of contributors, and weight and rank them on a pathophysiological basis.METHODS Patients who have undergone a lactulose or glucose hydrogen breath test to rule out small intestinal bacterial overgrowth(SIBO) for various clinical symptoms, including diarrhoea, weight loss, abdominal pain, cramping or bloating, were seen as eligible for inclusion in a retrospective single-centre study. Clinical data such as co-morbidities, medication, laboratory parameters and other possible risk factors have been identified from the electronic data system. Cases lacking or with substantially incomplete clinical data were excluded from the analysis. Suspected contributors were summarised under four different pathophysiological pathways(impaired gastric acid barrier, impaired intestinal clearance, immunosuppression and miscellaneous factors including thyroid gland variables) and investigated using the χ2 test, Student's t-test and logistic regression models.RESULTS A total of 1809 patients who had undergone hydrogen breath testing were analysed. Impairment of the gastric acid barrier(gastrectomy, odds ratio: OR = 3.5, PPI therapy OR = 1.4), impairment of intestinal clearance(any resecting gastric surgery OR = 2.6, any colonicresection OR = 1.9, stenosis OR = 3.4, gastroparesis OR = 3.4, neuropathy 2.2), immunological factors(any drug-induced immunosuppression OR = 1.8), altered thyroid gland metabolism(hypothyroidism OR = 2.6, levothyroxine therapy OR = 3.0) and diabetes mellitus(OR = 1.9) were associated significantly to SIBO. Any abdominal surgery, ileocecal resection, vagotomy or Ig A-deficiency did not have any influence, and a history of appendectomy decreased the risk of SIBO. Multivariate analysis revealed gastric surgery, stenoses, medical immunosuppression and levothyroxine to be the strongest predictors. Levothyroxine therapy was the strongest contributor in a simplified model(OR = 3.0).CONCLUSION The most important contributors for the development of SIBO in ascending order are immunosuppression, impairment of intestinal clearance and levothyroxine use, but they do not sufficiently explain its emergence.

Cisapride decreasing orocecal transit time in patients with nonalcoholic steatohepatitis

BACKGROUND : Altered small-intestine motility, lengthening of orocecal transit time (OCTT), and small-intestinal bacterial overgrowth (SIBO) have been detected in patients with nonalcoholic steatohepatitis (NASH). These changes might be related to the progressive course and poor prognosis of the disease. This study was undertaken to investigate the effect of 4-week treatment with cisapride on OCTT. METHODS: Ten NASH patients without diabetes were included. Ten healthy individuals served as controls. OCTT was measured by lactulose breath test (LBT). Anti- endotoxin core antibodies (EndoCAb) IgG were also examined. The effect of cisapride (10 mg TID during 4 weeks) on LBT and serum EndoCAb IgG levels in NASH patients was investigated. RESULTS: The NASH patients had more significantly prolonged OCTT (95±17 min) than the controls (59±18 min, P=0.00032). Cisapride administration decreased OCTT (from 95±17 min to 83±19 min, P=0.037), basal breathed H2 (from 9.87±1.60 ppm to 8.61±1.63 ppm, P=0.046) and EndoCAb IgG titers (from 5.24±0.68 GMU/ ml to 4.20±0.72 GMU/ml, P=0.013) in NASH patients. CONCLUSIONS: The present data suggest the existence of deranged intestinal motility and endotoxemia in NASH patients. Cisapride administration during 4 weeks possibly restore intestinal motility and ameliorate endotoxemia in NASH patients.

Gilbert’s syndrome coexisting with hereditary spherocytosis might not be rare: Six case reports

BACKGROUND Both Gilbert's syndrome(GS)and hereditary spherocytosis(HS)are common genetic disorders.However,comorbidity of GS with HS has always been considered a rare phenomenon,and it can impede accurate diagnoses in the presence of isolated unconjugated hyperbilirubinemia.CASE SUMMARY In a study on Levitt’s carbon monoxide(CO)breath test for the differential diagnosis of isolated hyperbilirubinemia,we found six GS patients with HS in 6 mo.The patients,including five males and one female,aged 25-58 years,were from four families and generally in good health.Their chronic fluctuating jaundice and/or hyperbilirubinemia had been diagnosed as simple constitutional jaundice for 6-30 years.Liver function tests showed isolated unconjugated hyperbilirubinemia with serum total bilirubin ranging from 20.7-75.4μmol/L.Blood hemoglobin was normal in five cases,and slightly decreased in one(11.5 g/dL).Overt hemolytic signs were absent,while erythrocyte lifespan determined by the newly developed Levitt’s CO breath test was significantly short(15-50 d),definitely demonstrating the presence of hemolysis.Given that their unconjugated hyperbilirubinemia compared inappropriately with hemolytic severity,as indicated by the hemoglobin level,further combined genetic tests for both UGT1A1 and hereditary erythrocyte deficiencies were conducted.These tests confirmed,at last,the coexistence of GS with HS.CONCLUSION Comorbidity of GS and HS might not be uncommon in isolated unconjugated hyperbilirubinemia.While CO breath test would sensitively detect the hemolysis,the discordance between the hyperbilirubinemia and hemoglobin level could strongly indicate the coexistence of GS and HS.

Parasympathetic Dysfunction in Black African Patients with Heart Failure:A Cross-Sectional Study in Sub-Saharan Africa

Background: Heart Failure (HF) is a major public health problem worldwide. Neurohormonal changes associated with HF are current therapeutic targets. The parasympathetic system in HF has not been well studied especially in black Africans. Aim: This study aimed to report on the prevalence and determinants of parasympathetic dysfunction in patients with heart failure in sub-Saharan Africa. Methods: We conducted a cross-sectional study between December 2017 and April 2018 in the outpatient and inpatient departments in two teaching hospitals in Yaounde-Cameroon. Cases were patients with HF matched with controls without HF according to age, sex, and risk factors (hypertension, diabetes, and obesity). We assessed the parasympathetic function via the Deep Breathing Test using an electrocardiograph. Results: We recruited 35 patients in each group. The mean age was 57 ± 11.68 years. Vagal dysfunction was seen in 51.4% of cases and 11.4% of controls (aOR: 10.1 [95% CI: 2.7 - 38.3], p = 0.001). This risk increased with the severity of HF-aOR: 11.8, [95% CI: 1.8 - 77.9], p = 0.01 for dyspnea stage III-IV, and aOR: 9.27, [95% CI: 1.3 - 65.3], p = 0.025) for HF with reduced Ejection fraction. This risk was not associated with the classic cardiovascular risk factors. Conclusion: Parasympathetic dysfunction as assessed with the Deep Breathing Test was seen in over half of the patients with HF and this was associated with the severity and type of HF.

Measurement of liver function for patients with cirrhosis by ^13C-methacetin breath test compared with Child-Pugh score and routine liver function tests

^13C-methacetin breath test was used for the evaluation of liver function, as for quantitative data could be achieved using this method, it had the characteristics of safety, quantification, and repetition and got recognition gradually through the world. We began this ^13C- methacetin test to assess liver function of patients with cirrhosis from January 2002. The aim of this study was to explore the characteristic of this test for liver function evaluation and explore the correlation of this method with some clinical liver biochemical parameters and Child-Pugh score.

Patients with breath test positive are necessary to be identified from irritable bowel syndrome:a clinical trial based on microbiomics and rifaximin sensitivity

Background:As a non-invasive and effective diagnostic method for small intestinal bacterial overgrowth(SIBO),wild-use of breath test(BT)has demonstrated a high comorbidity rate in patients with diarrhea-predominant irritable bowel syndrome(IBS-D)and SIBO.Patients overlapping with SIBO respond better to rifaximin therapy than those with IBS-D only.Gut microbiota plays a critical role in both of these two diseases.We aimed to determine the microbial difference between IBS-D overlapping with/without SIBO,and to study the underlying mechanism of its sensitivity to rifaximin.Methods:Patients with IBS-D were categorized as BT-negative(IBSN)and BT-positive(IBSP).Healthy volunteers(BT-negative)were enrolled as healthy control.The patients were clinically evaluated before and after rifaximin treatment(0.4 g bid,4 weeks).Blood,intestine,and stool samples were collected for cytokine assessment and gut microbial analyses.Results:Clinical complaints and microbial abundance were significantly higher in IBSP than in IBSN.In contrast,severe systemic inflammation and more active bacterial invasion function that were associated with enrichment of opportunistic pathogens were seen in IBSN.The symptoms of IBSP patients were relieved in different degrees after therapy,but the symptoms of IBSN rarely changed.We also found that the presence of IBSN-enriched genera(Enterobacter and Enterococcus)are unaffected by rifaximin therapy.Conclusions:IBS-D patients overlapping with SIBO showed noticeably different fecal microbial composition and function compared with IBS-D only.The better response to rifaximin in those comorbid patients might associate with their different gut microbiota,which suggests that BT is necessary before IBS-D diagnosis and use of rifaximin.Registration:Chinese Clinical Trial Registry,ChiCTR1800017911.