H. pylori infection and visceral hypersensitivity in patients with irritable bowel syndrome

Helicobacter pylori Infection—A Risk Factor for Irritable Bowel Syndrome? An Updated Systematic Review and Meta-Analysis

Nowadays, the relationship between Helicobacter pylori infection (HPI) and irritable bowel syndrome (IBS) remains controversial. Objective: The aim of this study is to investigate the relationship between HPI and IBS through a systematic review and meta-analysis based on the current evidence. Methods: We performed a systematic literature search in electronic databases (PubMed, EMBASE, and the Cochrane library) by computer to identify all reports published before 8 August 2021. The odds ratio (OR) and confidence interval (CI) were calculated to evaluate the association between HPI and IBS. Subgroup analyses were conducted for further assessment and exploration of heterogeneity sources. In addition, we assessed publication bias through funnel plots, Egger’s test, and Begg’s test. Finally, we conducted a sensitivity analysis to evaluate the robustness of the results. Results: Thirteen studies with 13,173 participants were included in the meta-analysis. The pooled OR of the association between HPI and IBS was 1.03 (95% CI [0.80,1.31]; p = 0.84). The adjusted OR of the association between HPI and IBS after excluding the studies with confounding factors defined by our team was 1.29 (95% CI [1.03,1.62]; p = 0.03). We found a positive association between HPI and IBS-D (diarrhea subtype) (OR: 1.54; 95% CI [1.22,1.95]; p = 0.0003). The OR of the relationship between cytotoxin-associated gene A (Cag A) positive HPI and IBS was 4.3 (95% CI [0.51,36.17]; p = 0.18). Conclusions: The likelihood of HPI in IBS patients is relatively higher than that of non-IBS participants but not statistically significant, implying that HPI is not significantly associated with IBS, albeit we may underestimate this association. Moreover, we found a positive association between HPI and IBS-D. We also observed an increased likelihood of Cag-A positive HPI in IBS patients than that of non-IBS participants but not statistically significant.

A questionnaire-based survey on the etiopathogenesis of chronic constipation during a medical check-up in Japan

The study group of the Japanese Society of Gastroenterology released evidence-based clinical practice guidelines for chronic constipation (CC) in 2017, and irritable bowel syndrome (IBS) was treated as one of the causes of CC. We examined the differences in characteristics between IBS and non-IBS subjects with CC who underwent a medical check-up in Japan. A total of 10,658 subjects participated in this study, and we focused on 467 subjects who fulfilled the diagnostic criteria of CC using a questionnaire survey. The number of IBS subjects was 21, and they had sleep disorders, were more symptomatic (e.g., abdominal pain, abdominal bloating/distension, feeling stressed, annoyance, lack of motivation, fatigue upon waking, and feeling depressed), and had more episodes of sensation of incomplete evacuation and anorectal obstruction/blockage during defecation than non-IBS subjects. Furthermore, stool frequency of IBS subjects was significantly different from non-IBS subjects. Multivariate ordinal logistic regression analysis revealed that the factors associated with a higher stool frequency were IBS [odds ratio (OR), 2.46; 95% confidence interval (CI), 1.00–6.05; p = 0.049], male sex (OR, 1.97; 95% CI, 1.20–3.23; p = 0.007), and regular exercise (OR, 1.80; 95% CI, 1.05–3.07; p = 0.033). These findings suggest that IBS has unique characteristics in subjects with CC.

Risk for Irritable Bowel Syndrome in Patients with Helicobacter Pylori Infection: A Nationwide Population-Based Study Cohort Study in Taiwan

Background: The association between Helicobacter pylori (H. pylori) infection and the risk of developing irritable bowel syndrome (IBS) has yet to be investigated; thus, we conducted this nationwide cohort study to examine the association in patients from Taiwan. Methods: A total of approximately 2669 individuals with newly diagnosed H. pylori infection and 10,676 age- and sex-matched patients without a diagnosis of H. pylori infection from 2000 to 2013 were identified from Taiwan’s National Health Insurance Research Database. The Kaplan–Meier method was used to determine the cumulative incidence of H. pylori infection in each cohort. Whether the patient underwent H. pylori eradication therapy was also determined. Results: The cumulative incidence of IBS was higher in the H. pylori-infected cohort than in the comparison cohort (log-rank test, p < 0.001). After adjustment for potential confounders, H. pylori infection was associated with a significantly increased risk of IBS (adjusted hazard ratio (aHR) 3.108, p < 0.001). In addition, the H. pylori-infected cohort who did not receive eradication therapy had a higher risk of IBS than the non-H. pylori-infected cohort (adjusted HR 4.16, p < 0.001). The H. pylori-infected cohort who received eradication therapy had a lower risk of IBS than the comparison cohort (adjusted HR 0.464, p = 0.037). Conclusions: Based on a retrospective follow-up, nationwide study in Taiwan, H. pylori infection was associated with an increased risk of IBS; however, aggressive H. pylori infection eradication therapy can also reduce the risk of IBS. Further underlying biological mechanistic research is needed.

The Association between Helicobacter pylori Infection and Irritable Bowel Syndrome: A Meta-Analysis

The association of Helicobacter pylori (H. pylori) infection with functional dyspepsia has been well studied. However, the data on the relationship between H. pylori infection and irritable bowel syndrome (IBS) are conflicting. This study aims to elucidate the association between H. pylori infection and IBS. PubMed, Cochrane Library, CINAHL and SCOPUS databases were searched to identify eligible English articles published up to December 2019. Cross-sectional studies, case–control studies and cohort studies reporting both prevalence of H. pylori infection and IBS were selected for the detailed review. The pooled odds ratio (ORs) and their 95% confidence interval (CI) were calculated. A total of 7269 individuals in four cross-sectional studies and six case-control studies were included. The prevalence of H. pylori infection ranged from 12.8% to 73.4% in the control group, and 9.7% to 72.1% in the IBS group. The combined OR for H. pylori infection was 1.10 (95% CI: 0.93–1.29, I²: 37.5%). In a subgroup analysis of IBS defined according to Rome criteria, the OR for H. pylori infection was 1.10 (95% CI: 0.93–1.30, I² = 31.7%). In this meta-analysis, H. pylori infection was not significantly associated with IBS. Well-designed studies are needed to identify the relationship between H. pylori infection and IBS.

Is there an association between Helicobacter pylori infection and irritable bowel syndrome? A meta-analysis

BACKGROUND

Irritable bowel syndrome (IBS) is a prevalent and debilitating gastrointestinal condition. Research has reported persistent, low-grade mucosal inflammation and significant overlaps between patients with IBS and those with dyspepsia, suggesting a possible pathogenic role of Helicobacter pylori (H. pylori) in IBS. This study therefore aimed to provide the first systematic review and meta-analysis on the association between H. pylori infection and IBS.

AIM

To investigate the association between H. pylori infection and IBS.

METHODS

Using the keywords "H. pylori OR Helicobacter OR Helicobacter pylori OR infection" AND "irritable bowel syndrome OR IBS", a preliminary search of PubMed, Medline, Embase, Cochrane Database of Systematic Reviews, Web of Science, Google Scholar and WanFang databases yielded 2924 papers published in English between 1 January 1960 and 1 June 2018. Attempts were also made to search grey literature.

RESULTS

A total of 13 clinical studies were systematically reviewed and nine studies were included in the final meta-analysis. Random-effects meta-analysis found a slight increased likelihood of H. pylori infection in patients with IBS, albeit this was not statistically significant (pooled odds ratio 1.47, 95% confidence interval: 0.90-2.40, P = 0.123). It must also be acknowledged that all of the available studies reported only crude odd ratios. H. pylori eradication therapy also does not appear to improve IBS symptoms. Although publication bias was not observed in the funnel plot, there was a high degree of heterogeneity amongst the studies included in the meta-analysis (I 2 = 87.38%).

CONCLUSION

Overall, current evidence does not support an association between IBS and H. pylori infection. Further rigorous and detailed studies with larger sample sizes and after H. pylori eradication therapy are warranted.

Helicobacter pylori eradication in dyspepsia: New evidence for symptomatic benefit

A causal relationship between Helicobacter pylori (H. pylori) infection and functional dyspepsia (FD) is well established in a subset of infected patients. In the Kyoto and Maastricht/Florence consensus reports H. pylori-associated dyspepsia is defined as an independent entity distinct from FD. H. pylori eradication is therefore the most cost-effective approach for infected patients with dyspeptic symptoms and superior to other medical therapies, such as Proton Pump Inhibitors. The therapeutic gain of H.pylori eradication for symptom relief compared to other therapeutic options is significant with the number needed to benefit of 12. Furthermore H.pylori cures chronic gastritis except in severe cases of atrophic gastritis and may prevent severe complications attributable to the infection. Several pathophysiological mechanisms are suggested for the generation of symptoms and are related to the distinct topographic expression and degree of gastric inflammation as well as changes of gastric acid secretion, gastrointestinal motility and visceral hypersensitivity.

Potential prebiotics and their transmission mechanisms: Recent approaches

Prebiotics are non-digestible carbohydrates which can be used as prime source of energy for gut microflora. These can be naturally occurring in fruit and vegetables or can be made synthetically by enzymatic digestions. New versatile sources of prebiotics had been found nowadays for economic commercialization. This review will decipher on highlighting the importance of prebiotics in immunomodulation and nutrient absorption abilities of gut, as it is important for the anti-effective capacity of the organism especially in the neonatal period. Moreover, new prebiotics transmission strategies with higher penetrating capacity such as microencapsulation and immobilization have been discussed. In addition to this, literature had shown the modulation of gut microflora by the continuous use of prebiotics in many disorders so here, the role of prebiotics in health-related issues such as diabetes and inflammatory bowel disease (IBS) have been explained.

The possible role of bacteria, viruses, and parasites in initiation and exacerbation of irritable bowel syndrome

Irritable bowel syndrome (IBS) is a prolonged and disabling functional gastrointestinal disorder with the incidence rate of 18% in the world. IBS could seriously affect lifetime of patients and cause high economic burden on the community. The pathophysiology of the IBS is hardly understood, whereas several possible mechanisms, such as visceral hypersensitivity, irregular gut motility, abnormal brain-gut relations, and the role of infectious agents, are implicated in initiation and development of this syndrome. Different studies demonstrated an alteration in B-lymphocytes, mast cells (MC), T-lymphocytes, and cytokine concentrations in intestinal mucosa or systemic circulation that are likely to contribute to the formation of the IBS. Therefore, IBS could be developed in those with genetic predisposition. Infections' role in initiation and exacerbation of IBS has been investigated by quite several clinical studies; moreover, the possible role of some pathogens in development and exacerbation of this disease has been described. It appears that the main obligatory pathogens correspond with the IBS disease, Clostridium difficile, Escherichia coli, Mycobacterium avium subspecies paratuberculosis, Campylobacter concisus, Campylobacter jejuni, Chlamydia trachomatis, Helicobacter pylori, Pseudomonas aeruginosa, Salmonella spp, Shigella spp, and viruses, particularly noroviruses. A number of pathogenic parasites (Blastocystis, Dientamoeba fragilis, and Giardia lamblia) may also be involved in the progression and exacerbation of the disease. Based on the current knowledge, the current study concludes that the most common bacterial, viral, and parasitic pathogens may be involved in the development and progression of IBS.

Definition, Pathogenesis, and Management of That Cursed Dyspepsia

Dyspepsia is an umbrella term used to encompass a number of symptoms thought to originate from the upper gastrointestinal tract. These symptoms are relatively nonspecific; not surprisingly, therefore, a myriad of conditions may present with any one or a combination of these symptoms. Therein lays the clinician's first challenge: detecting the minority who may have a potentially life-threatening disorder, such as gastric cancer, from a population whose symptoms are, for the most part, considered functional in origin. The second challenge lies in the definition and management of those individuals with functional dyspepsia (FD); the major focus of this review. The Rome process has addressed the issue of FD definition and a look back at the evolution of Rome criteria for this disorder illustrates the complexities that have so frustrated us. There has been no shortage of hypotheses to explain symptom pathogenesis in FD; initially focused on gastric sensorimotor dysfunction, these have now strayed well into the duodenum and have come to entertain such factors as immune responses and the microbiome. FD has proven to be an equally challenging area for therapeutics; while the staple approaches of acid suppression and eradication of Helicobacter pylori have some limited efficacy in select populations, strategies to ameliorate symptoms in the majority of sufferers based on presumed pathophysiology have largely foundered. Lacking a validated biomarker(s) FD continues to be an elusive target and is likely to remain so until we can better define the various phenotypes that it must surely contain.

Blastocystis subtypes isolated from irritable bowel syndrome patients and co-infection with Helicobacter pylori

Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disease presenting clinically by abdominal pain with alteration of bowel habits. Although IBS has uncertain etiology, chronic gut inflammation due to persistent exposure to an infectious agent including Blastocystis sp. was proposed. The aim of this study was to detect the prevalence of Blastocystis sp. subtype (ST) isolated from stool of IBS patients and to assess Blastocystis sp. and H. pylori co-infection in IBS patients from Beni-Suef Governorate, Egypt. Stool samples were collected from 115 IBS patients, following Rome III criteria. All stool samples were microscopically examined by wet mount and permanent trichrome stain, cultured on Jones' medium with further sequencing of positive Blastocystis isolates and screened for detection of H. pylori coproantigen. Blastocystis sp. was the predominant parasite in IBS patients; it had statistical significant association with both rural residence (OR = 10) and flatulence (OR = 8.2). There was a predominance of Blastocystis sp. ST3 (81%) followed by ST1 (19%). Blastocystis culture results (19.1%) were superior than microscopy (16.5%). The majority of Blastocystis-positive IBS patients (72.7%) were co-infected with H. pylori with statistical significance; however, H. pylori was higher in Blastocystis-negative IBS patients (47/64) than in Blastocystis-positive IBS patients (17/64). Interestingly, IBS is usually associated with gut dysbiosis, while the most prevalent parasite in our IBS patients was Blastocystis sp., which is frequently found in asymptomatic individuals. Whether Blastocystis sp. is a cause or a consequence of IBS still needs further investigation, with a particular focus on correlation of IBS with different Blastocystis sp. subtypes and gut microbiomes.

Effect of Helicobacter pylori infection on the link between GLP-1 expression and motility of the gastrointestinal tract

Background

Although Helicobacter pylori (H. pylori) infection is closely associated with the development of peptic ulcer, its involvement in pathophysiology in the lower intestinal tract and gastrointestinal (GI) motility remains unclear. Glucagon-like peptide-1 (GLP-1) is a gut hormone produced in the lower intestinal tract and involved in GI motility. Here, we investigated the effect of H. pylori infection on the link between GLP-1 expression and motility of the GI tract.

Methods

C57BL/6 mice were inoculated with a H. pylori strain. Twelve weeks later, the H. pylori-infected mice underwent H. pylori eradication treatment. GI tissues were obtained from the mice at various time intervals, and evaluated for the severity of gastric inflammatory cell infiltration and immunohistochemical expression of GLP-1 and PAX6 in the colonic mucosa. Gastrointestinal transit time (GITT) was measured by administration of carmine-red solution.

Results

GLP-1 was expressed in the endocrine cells of the colonic mucosa, and PAX6 immunoreactivity was co-localized in such cells. The numbers of GLP-1- and PAX6-positive cells in the colon were significantly increased at 12 weeks after H. pylori infection and showed a positive correlation with each other. The GITT was significantly longer in H. pylori-infected mice than in non-infected controls and showed a positive correlation with GLP-1 expression. When H. pylori-infected mice underwent H. pylori eradication, GITT and PAX6/GLP-1 expression did not differ significantly from those in untreated H. pylori-infected mice.

Conclusions

H. pylori infection may impair GI motility by enhancing the colonic GLP-1/PAX6 expression.

Irritable bowel syndrome is associated with gastroesophageal reflux symptom but not erosive esophagitis

BACKGROUND/AIMS

Although several studies have suggested overlaps between gastroesophageal reflux symptom and irritable bowel syndrome (IBS), the studies for the association between erosive esophagitis and IBS are rare. The aim of this study was to evaluate the association among IBS, non-erosive reflux disease (NERD), and erosive esophagitis.

METHODS

A total of 2,769 participants completed questionnaires and underwent esophagogastroduodenoscopy and colonoscopy. IBS was diagnosed by Rome III; NERD was defined as heartburn or acid regurgitation occurring at least once per week without erosive esophagitis. Erosive esophagitis was defined by Los Angeles classification. Psychological distress was evaluated with modified 4 dimensions from revised Hopkins symptom checklist 90.

RESULTS

Psychological distress was associated with both IBS and NERD, but not with erosive esophagitis. IBS was associated with somatization (adjusted OR, 2.88; 95% CI, 1.55-5.36; P < 0.001), anxiety (adjusted OR, 2.82; 95% CI, 1.36-5.88; P = 0.005), and hostility (adjusted OR, 2.06; 95% CI, 1.10-3.87; P = 0.024) and NERD was associated with somatization (adjusted OR, 5.65; 95% CI, 2.92-10.98; P < 0.001) and anxiety (adjusted OR, 3.29; 95% CI, 1.47-7.34; P = 0.004). Erosive esophagitis was associated with somatization (adjusted OR, 2.69; 95% CI, 1.26-7.91; P < 0.001). Hiatal hernia and male sex were related with erosive esophagitis but not with IBS or NERD. H. pylori had an inverse relationship with erosive esophagitis, but had no association with IBS. Whereas IBS was positively associated with NERD (adjusted OR, 2.72; 95% CI, 1.84-4.03; P < 0.001), it had no association with erosive esophagitis.

CONCLUSIONS

IBS shared many risk factors with NERD but not with erosive esophagitis. It partially explains why IBS was associated with NERD, but not with erosive esophagitis.

Risk factors for constipation-predominant irritable bowel syndrome: an analysis of 100 cases

AIM: To investigate the risk factors for constipation-predominant irritable bowel syndrome (C-IBS) to guide treatment and prevention of the disease.

METHODS: This was a 1:1 case-control study. A questionnaire survey was conducted among 100 patients who were diagnosed with C-IBS and 100 healthy volunteers from November 2010 to January 2011. The questionnaire requested general information and information on life style and psychological factors (depression). Statistical analysis was performed using SPSS17.0 software.

RESULTS: A family history of constipation (RR = 6.493), regular defecation (RR = 0.120) and depression (RR = 2.195) were independently associated with the incidence of C-IBS (all P < 0.05). A family history of constipation and depression were risk factors for C-IBS, whereas regular defecation was a protective factor.

CONCLUSION: Lifestyle and mental status can affect the incidence of C-IBS. Improvement of lifestyle and mental intervention can prevent and relieve C-IBS.

The clinical significances of irritable bowel syndrome in Taiwan

BACKGROUND AND AIM

According to the Rome III definition, irritable bowel syndrome (IBS) has been a biopsychosocial dysfunction. We tried to know whether the IBS clinical manifestations were comparable to other countries.

METHOD

We have reviewed the IBS publications in Taiwan, thus its clinical significances are summarized and compared to others.

RESULTS

Among a selected population of paid physical checkup, the Rome I & II criteria defined prevalences were 17.5% and 22.1%, respectively without an observed female predominance. However, female was a factor leading to constipation predominant IBS (C-IBS). Taiwan IBS patients did excessively consume society resource in terms of physician visits and absenteeism. They also had more chance of cholecystectomy, whereas normal appendix was often found in case of appendectomy. Overlapping extra-colonic manifestations, e.g. dyspepsia and lower urinary tract symptoms were common. Helicobacter pylori infection and female gender were closely related to the coexisted dyspepsia. Various psychiatric disturbances were also confirmed here. Intestinal transit correlated well with bowel symptoms, e.g. slow in constipation but fast in diarrhea. Diminished cholinergic activity was observed among the C-IBS patients. Various agents including mebeverine, pinaverium, peppermint oil, smectitie and tegarserod did somewhat improve IBS symptoms. Unfortunately, the IBS knowledge was not well understood among the medical professionals.

CONCLUSIONS

IBS is common in Taiwan, its impacts on the society are similarly observed while female gender often results in severe impacts. Disordered motility and cholinergic nervous system are likely some of its pathogeneses. Current recommended treatments are effectively demonstrated.

Helicobacter pylori and gastrointestinal symptoms in school children in Russia

BACKGROUND AND AIMS

Helicobacter pylori is considered to be the major cause of chronic gastritis and duodenal ulcer disease recurrence in childhood. However, the association between H. pylori and recurrent abdominal pain (RAP) syndrome is still controversial. Therefore, the spectrum of clinical variants of gastrointestinal symptoms associated with H. pylori-positive status was studied in consecutive symptomatic children who were undergoing diagnostic endoscopy.

METHODS

A consecutive series of 225 school children from the Ural area of Russia (mean age 11.1 + 1.4 years, age range 7-15 years) who presented with RAP were investigated using esophagogastroduodenoscopy, including three antral biopsies for histology and polymerase chain reaction. Helicobacter pylori immunoglobulin G antibodies were found using a second-generation enzyme immunoassay. Information about the clinical symptoms was collected using a special questionnaire.

RESULTS

The authors found a high incidence of H. pylori infection (80%) and peptic ulcers (16%) in 225 school children from the Ural area of Russia who were referred for upper gastrointestinal (UGI) endoscopy for chronic abdominal pain. Of the overall 225 symptomatic children who underwent endoscopy, 182 (80,8%) were found to be H. pylori-positive. Duodenal ulcers were detected in 36 H. pylori-positive children. A family history of peptic ulcers was significantly more frequent in the children infected with H. pylori (P < 0.001). Symptom score and duration of symptoms were similar, but night-time pain (P < 0.0001) and fasting pain relieved by food (P < 0.001) were more frequent in the H. pylori-positive children as compared with the H. pylori-negative children.

CONCLUSIONS

The present results provide further evidence for a significant association between H. pylori and some patterns of gastrointestinal symptoms in children who underwent UGI endoscopy in order to exclude an organic cause of severe chronic gastrointestinal disorders.

Chronic fatigue syndrome: lactic acid bacteria may be of therapeutic value

Chronic fatigue syndrome (CFS) is complex illness with unknown aetiology. Recent research shows that patients with CFS have marked alterations in microbial flora, including lowered levels of bifidobacteria and small intestinal bacterial overgrowth (SIBO). Research also indicates that CFS patients are under increased oxidative stress, have a type 2 helper cell dominate cytokine profile, frequently report allergies, have altered essential fatty acid (EFA) status and may have malabsorption of certain micronutrients. Lactic acid bacteria (LAB) have the potential to influence the immune system in CFS patients by supporting T helper cell 1 driven cellular immunity and may decrease allergies. In addition LAB are strong antioxidants, may improve EFA status, can enhance absorption of micronutrients by protecting the intestinal epithelial barrier, and have been used to treat SIBO. It is our contention that LAB may have a therapeutic role in the treatment of CFS.