Helicobacter pylori infection is associated with fecal biomarkers of environmental enteric dysfunction but not with the nutritional status of children living in Bangladesh

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

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

Lack of Associations between Environmental Exposures and Environmental Enteric Dysfunction among 18-Month-Old Children in Rural Malawi

Environmental enteric dysfunction (EED) is common and contributes to linear growth faltering (stunting) and mortality among children in low-resource settings. A few studies on the environmental causes of EED have been conducted but the exact exposures that cause or predispose children to EED are context-specific and not clear. This study aimed to assess associations between selected environmental exposures and EED markers among 620 18-month-old children. This was a secondary analysis of data from Malawian children who participated in a randomized controlled trial (iLiNS-DYAD, registered at clinicaltrials.gov as NCT01239693) from birth to 18 months of age. Data on environmental exposures, including drinking water source, sanitation, exposure to animals, housing materials, season, residential area, and food insecurity were collected at enrolment. Biomarkers of EED included concentrations of calprotectin, regenerating 1B protein (REG1B), and alpha-1-antitrypsin from stool samples to assess intestinal inflammation, repair, and permeability, respectively. We performed bivariate and multivariable analyses to assess associations between environmental exposures and EED biomarkers. Adjusting for possible confounders, we did not find associations between the selected environmental exposures and the three biomarkers. These results do not provide support for our hypothesis that the studied adverse environmental exposures are associated with increased concentrations of children's EED markers in rural Malawi.

Inadequate Vitamin C Intake and Intestinal Inflammation Are Associated with Multiple Micronutrient Deficiency in Young Children: Results from a Multi-Country Birth Cohort Study

Children living in resource-limited settings often suffer from multiple micronutrient deficiencies (MMD). However, there lacks evidence on the correlates of MMD in young children. We investigated the role of diets, water, sanitation and hygiene practice, enteric infections, and impaired gut health on MMD in children at 24 months of age using data from the multi-country MAL-ED birth cohort study. Co-existence of more than one micronutrient deficiency (e.g., anemia, iron, zinc, or retinol deficiency) was considered as MMD. We characterized intestinal inflammation by fecal concentrations of myeloperoxidase (MPO) and neopterin (NEO) measured in the non-diarrheal stool samples. Bayesian network analysis was applied to investigate the factors associated with MMD. A total of 1093 children were included in this analysis. Overall, 47.6% of the children had MMD, with the highest prevalence in Pakistan (90.1%) and lowest in Brazil (6.3%). MMD was inversely associated with the female sex [OR: 0.72, 95% CI: 0.54, 0.92]. A greater risk of MMD was associated with lower vitamin C intake [OR: 0.70, 95% CI: 0.48, 0.94] and increased fecal concentrations of MPO [OR: 1.31, 95% CI: 1.08, 1.51]. The study results imply the importance of effective strategies to ameliorate gut health and improve nutrient intake during the early years of life.

Fecal Calprotectin in Children Can Differentiate Between Different Gastrointestinal Diseases

BACKGROUND: Calprotectin is a 36 kDa member of the S100 family of proteins. It is derived predominantly from neutrophils and has direct antimicrobial effects and a role within the innate immune response. Calprotectin is found in various body fluids in proportion to the degree of any existing inflammation and its concentration in feces is about 6 times that of plasma. Measurement of fecal calprotectin is a useful surrogate marker of gastrointestinal inflammation. It has a high negative predictive value in ruling out inflammatory bowel disease (IBD) in undiagnosed, symptomatic patients and high sensitivity for diagnosing the disease making it useful as a tool for prioritizing endoscopy. In patients with known IBD, fecal calprotectin can be a useful tool to assist management, providing evidence of relapse or mucosal healing to enable therapy to be intensified or reduced. AIM: The present study aimed to discuss the use of calprotectin for the diagnosis of IBD and some of the other ways in which the test may be useful in the management of gastroenterology patients. METHODS: A cross-sectional study on children with significant gastrointestinal diseases attending to pediatric department at Menoufia University, with a total number of 180 patients in addition to 30 normal children as control according to sample size calculation. The children are allocated into seven groups according to the final diagnosis to Group (1): 30 patients with IBD, Group (2): 20 patients with eosinophilic colitis, Group (3): 30 patients with Helicobacter pylori infection, Group (4): 40 patients with functional constipation, Group (5): 30 patients with cow milk allergy, Group (6): 30 patients with Celiac disease, and Group (7): 30 normal children as control. RESULTS: In cow milk protein allergic patients with marked GI presentation in the form of bloody diarrhea and/or abdominal distension, the mean fecal calprotectin (FC) was 1260 ± 625 μg/g. FC has decreased after 2−4 weeks of elimination of cow milk products to 420 ± 190 μg/g. Patient with inflammatory bowel disease had mean FC 4640 ± 850 μg/g, decreased after medical treatment and resolution of symptoms to 1360 ± 520 μg/g. In H. pylori infection detected by upper GI endoscopy and histopathology with positive stool antigen the mean FC was 78.9 ± 25.1 μg/g. Celiac disease patients had mean fecal calprotectin 456 ± 123 μg/g. Eosinophilic esophagitis had mean fecal calprotectin 4.2 ± 2.9 μg/g. Functional constipation patients had mean fecal calprotectin 23.6 ± 21.8 μg/g. Normal control children had mean fecal calprotectin 4.1 ± 6.9 μg/g. CONCLUSION: According to the results of previous studies, fecal calprotectin can be considered as a biomarker to differentiate between IBS and organic gastrointestinal disorders. However, due to the limitations of pre-analysis, a low fecal calprotectin concentration may not necessarily be considered as the reason for the absence of IBD.

MicroRNA Expression and Intestinal Permeability in Children Living in a Slum Area of Bangladesh

Introduction: MicroRNAs (miRNAs) are small, non-coding RNAs that post-transcriptionally regulate gene expression. Changes in miRNA expression have been reported in a number of intestinal diseases, in both tissue samples and readily accessible specimens like stools. Pathogenic infections, diet, toxins, and other environmental factors are believed to influence miRNA expression. However, modulation of miRNAs in humans is yet to be thoroughly investigated. In this study, we examined the expression levels of two human miRNAs (miRNA-122 and miRNA-21) in stool samples of a group of Bangladeshi children who had an altered/increased intestinal permeability (IIP). Methods: Stool samples were collected from children with IIP (L:M > 0.09) and normal intestinal permeability (NIP) (L:M ≤ 0.09). Quantitative PCR was performed to quantify the levels of miRNA-122 and miR-21 in stools. Commercial ELISA kits were used to measure gut inflammatory markers Calprotectin and REG1B. Serum samples were tested using Human Bio-Plex Pro Assays to quantify IL-1β, IL-2, IL-5, IL-10, IL-13, IFN-γ, and TNF-α. Total nucleic acid extracted from stool specimens were used to determine gut pathogens using TaqMan Array Card (TAC) system real-time polymerase chain reaction. Results: The expression levels of miRNA-122 (fold change 11.6; p < 0.001, 95% CI: 6.14-11.01) and miR-21 (fold change 10; p < 0.001, 95% CI: 5.05-10.78) in stool were upregulated in children with IIP than in children with normal intestinal permeability (NIP). Significant correlations were observed between stool levels of miR-122 and miR-21 and the inflammatory cytokines IL-1β, IL-2, IFN-γ, and TNF-α (p < 0.05). Children with IIP were frequently infected with rotavirus, Campylobacter jejuni, Bacteroides fragilis, adenovirus, norovirus, astrovirus, and various Escherichia coli strains (ETEC_STh, ETEC_STp, EAEC_aaiC, EAEC_aatA) (p < 0.001). miR-122 significantly correlated with the fecal inflammatory biomarkers REG1B (p = 0.015) and Calprotectin (p = 0.030), however miR-21 did not show any correlation with these fecal biomarkers.

Benefits and Risks of Smallholder Livestock Production on Child Nutrition in Low- and Middle-Income Countries

Livestock production may improve nutritional outcomes of pregnant women and children by increasing household income, availability of nutrient-dense foods, and women's empowerment. Nevertheless, the relationship is complex, and the nutritional status of children may be impaired by presence of or proximity to livestock and their pathogens. In this paper, we review the benefits and risks of livestock production on child nutrition. Evidence supports the nutritional benefits of livestock farming through income, production, and women's empowerment. Increasing animal source food consumption requires a combination of efforts, including improved animal management so that herd size is adequate to meet household income needs and consumption and addressing sociocultural and gendered norms. Evidence supports the inclusion of behavior change communication strategies into livestock production interventions to facilitate the sustainability of nutritional benefits over time, particularly interventions that engage women and foster dimensions of women's empowerment. In evaluating the risks of livestock production, evidence indicates that a broad range of enteric pathogens may chronically infect the intestines of children and, in combination with dietary deficits, may cause environmental enteric dysfunction (EED), a chronic inflammation of the gut. Some of the most important pathogens associated with EED are zoonotic in nature with livestock as their main reservoir. Very few studies have aimed to understand which livestock species contribute most to colonization with these pathogens, or how to reduce transmission. Control at the point of exposure has been investigated in a few studies, but much less effort has been spent on improving animal husbandry practices, which may have additional benefits. There is an urgent need for dedicated and long-term research to understand which livestock species contribute most to exposure of young children to zoonotic enteric pathogens, to test the potential of a wide range of intervention methods, to assess their effectiveness in randomized trials, and to assure their broad adaptation and sustainability. This review highlights the benefits and risks of livestock production on child nutrition. In addition to identifying research gaps, findings support inclusion of poor gut health as an immediate determinant of child undernutrition, expanding the established UNICEF framework which includes only inadequate diet and disease.

Infection with Blastocystis spp. and its association with enteric infections and environmental enteric dysfunction among slum-dwelling malnourished adults in Bangladesh

Background

Blastocystis spp. (Blastocystis) is a widely distributed gastrointestinal protist frequently reported in countries with tropical and sub-tropical climate. We sought to determine the factors associated with Blastocystis infection and investigate its role on biomarkers of intestinal health among slum-dwelling malnourished adults in Bangladesh.

Methodology

Total 524 malnourished adults with a body mass index ≤18.5 kg/m² were included in this analysis. Presence of Blastocystis in feces was evaluated by TaqMan Array Card assays.

Principal findings

Blastocystis was tested positive in 78.6% of the participants. Prevalence of infection with atypical strains of enteropathogenic Escherichia coli (aEPEC) (56% vs. 38%, p<0.001), and Trichuris trichiura (28% vs. 15%, p-value = 0.02) was significantly greater in adults with Blastocystis, while Giardia intestinalis was significantly lower (8% vs. 14%, p-value = 0.04) in Blastocystis positive adults. Malnourished adults who were living in households with high crowding index (aOR = 2.18; 95% CI = 1.11, 4.65; p-value = 0.03), and infected with aEPEC (aOR = 2.14; 95% CI = 1.35, 3.44; p-value = 0.001) and Trichuris trichiura (aOR = 1.97; 95% CI = 1.08, 3.77; p = 0.03) were more likely to be infected with Blastocystis. A significant negative relationship was observed between Blastocystis and fecal concentrations of alpha-1 antitrypsin (β = -0.1; 95% CI = -1.7, -0.1; p-value<0.001) and Reg1B (β = -3.6; 95% CI = -6.9, -3.0; p-value = 0.03).

Conclusions

The study findings suggest that the presence of Blastocystis in human intestine influences gut health and may have potential pathogenic role in presence of other pathogens.

Infection with Blastocystis, a neglected enteric pathogen, is frequently reported in tropical and sub-tropical countries. However, the epidemiology, pathogenicity and associated outcomes of Blastocystis in relation to enteric infections and Environmental Enteric Dysfunction (EED) remain inconclusive. In this study, the authors investigated the factors associated with Blastocystis infection and examined its association with enteric infections as well as fecal biomarkers of environmental enteric dysfunction among slum-dwelling malnourished adults in Bangladesh. The study findings exhibited that nearly 80% of the participants were infected with Blastocystis demonstrating a positive association with crowded living conditions. The authors observed a positive association of Blastocystis with atypical strain of Enteropathogenic Escherichia coli and Trichuris trichiura. The study results also corroborate that infection with Blastocystis had significant negative association with alpha-1 antitrypsin and Reg1B concentrations measured in the stool samples of the study participants. The findings of this study would help to reveal the pathogenic potential of Blastocystis and determine its role in contributing to altered gut health as well as EED in malnourished adults living in resource limited environments.

Seroprevalence of Helicobacter pylori and its association with metabolic syndrome in a rural community of Bangladesh

BACKGROUND AND AIM

As the interrelationship between Helicobacter pylori, metabolic syndrome (MetS), and non-alcoholic fatty liver disease (NAFLD) is controversial, we undertook a community-based study with the aim to find the seroprevalence of H. pylori and its relationship with MetS and NAFLD.

METHODS

This door-to-door survey was conducted among the adult subjects (≥18 years) of two villages (Charcharia of Dhaka district and Kharrah of Munshiganj district) of Bangladesh. Interviews using a structured questionnaire, clinical examination, anthropometric measurements, ultrasonogram of the liver, and biochemical tests were performed.

RESULTS

Of 1021 subjects, 781 responded (76.49%), and 767 were included in the final analysis (mean age 40.35 ± 15.56 years; female 63.5%). Anti-H. pylori antibodies were found in 418 of 767 (54.5%). There were no H. pylori serostatus association with MetS and diabetes mellitus (DM) in univariate or multivariate analysis (all P > 0.05). However, H. pylori seropositive subjects had lower systolic blood pressure (odds ratio [OR] = -2.95 [-5.58, -0.32]) and low density lipoprotein -cholesterol (OR -7.79 [-15, -0.57]) compared to seronegative subjects in the linear regression model. Seronegativity of H. pylori was associated with NALFD in univariate (P = 0.007) but not multivariate analysis (P = 0.086). There were no differences in the frequency of H. pylori seropositivity among the participants with nonobese compared to obese NAFLD (19/42 [45%] vs 43/99 [43.4%], P = 0.844).

CONCLUSION

In a rural community of Bangladesh, about 55% of the population were H. pylori seropositive, which was more common among the underweight than normal or obese subjects. However, there was no relationship observed between H. pylori seroprevalence and MetS, DM, or NAFLD.