Fecal biomarkers of environmental enteric dysfunction and associated factors among children aged 24-59 months in east Dembiya district, northwest Ethiopia

IMPACT OF NUTRITIONAL SUPPLEMENTATION ON ENVIRONMENTAL ENTERIC DYSFUNCTION (EED) IN CHILDREN LIVING IN RURAL AREAS: A SYSTEMATIC REVIEW

BACKGROUND

A staggering 99% of infant undernutrition mortality comes from Sub-Saharan Africa and South Asia. Despite multiple interventions focusing on nutrition adequacy, 2.7 million children worldwide remain associated with undernutrition-related mortality. The lack of impact from multiple interventions toward undernutrition reflects a strong reason to believe that EED is the missing link that sustains undernutrition in low-to-middle-income countries (LMICs). EED is a sub-clinical condition caused by repeated oral enteropathogenic and non-pathogenic fecal microbes exposure that causes intestinal villous malformation, multi-omics changes, chronic intestinal and systemic inflammation, and gut dysbiosis. EED impacts the absorptive capacity and the integrity of the gut, causing a cycle of undernutrition in children. There is currently no protocol for the diagnosis and treatment of EED, hence EED is widely believed to be highly prevalent and underdiagnosed in LMICs.

OBJECTIVE

To our knowledge, this is the first systematic review to study the impact of nutritional interventions on EED. Previous studies yielded inconsistent results, hence the synthesis of this information is essential in attaining a deeper understanding of EED to formulate new targets of intervention against child undernutrition.

METHODS

This systematic review is registered to PROSPERO (CRD42022363157) in accordance to PRISMA, using keywords referring to nutrient supplementation, EED, and child growth failure.

RESULTS

Eleven articles were eligible for review, comprising randomized controlled trials performed mainly in the African continent, with a total of 5689 healthy children eligible for analysis.

CONCLUSION

The systematic review illustrates that nutritional interventions have a minimal impact on EED biomarkers and linear growth and reflects the importance of understanding better the mechanisms causing EED and its consequences. It appears that the anabolic contribution of nutrition intervention to child growth is negated by EED.

Stunting among children aged 24-59 months and associations with sanitation, enteric infections, and environmental enteric dysfunction in rural northwest Ethiopia

Stunting is a public health issue of global concern. Despite, poor sanitation, diarrhea, parasitic infections, and environmental enteric dysfunction (EED) are associated with stunting, their link is poorly understood and has not been investigated in Ethiopia. This study was conducted to assess the associations of stunting with sanitation, enteric infections, and EED among children aged 24-59 months in rural northwest Ethiopia. A community-based cross-sectional study was conducted among 224 randomly selected children aged 24-59 months in rural areas of the east Dembiya district. We collected information on household food insecurity and dietary diversity using pre-tested questionnaires adopted from the food and nutrition technical assistance (FANTA) project. We used height-for-age-z score (HAZ) to define stunting. We also used the data collected to measure the environmental exposures of children to intestinal parasitic infections and fecal biomarkers of EED. A multivariable binary logistic regression model was used to assess the association of stunting with sanitation, enteric infections, and EED. Of the 224 children, 33% (95% CI 27, 39%) were stunted. Stunting in children was significantly associated with poor dietary intake (AOR 3.0, 95% CI 1.2, 7.3), open defecation practice (AOR 3.0, 95% CI 1.2, 7.9), presence of animal excreta in the living environment (AOR 3.4, 95% CI 1.2, 9.9), E. coli contamination of drinking water (AOR 4.2, 95% CI 1.1, 15.3), diarrheal disease incidence (AOR 3.4, 95% CI 1.5, 7.7), intestinal parasites in children (AOR 3.3, 95% CI 1.3, 8.8), and higher EED disease activity scores (AOR 2.9, 95% CI 1.2, 6.7). One-third of the children in the study area were stunted and this high prevalence of stunting was associated with poor dietary intake, poor hygiene and sanitation conditions, enteric infections, and EED. Thus, stunting can be prevented by improving sanitation and hygienic conditions to prevent repeated enteric infections in children and by promoting dietary diversity of children.

Putative Biomarkers of Environmental Enteric Disease Fail to Correlate in a Cross-Sectional Study in Two Study Sites in Sub-Saharan Africa

Environmental enteric dysfunction (EED) is an elusive, inflammatory syndrome of the small intestine thought to be associated with enterocyte loss and gut leakiness and lead to stunted child growth. To date, the gold standard for diagnosis is small intestine biopsy followed by histology. Several putative biomarkers for EED have been proposed and are widely used in the field. Here, we assessed in a cross-sectional study of children aged 2–5 years for a large set of biomarkers including markers of protein exudation (duodenal and fecal alpha-1-antitrypsin (AAT)), inflammation (duodenal and fecal calprotectin, duodenal, fecal and blood immunoglobulins, blood cytokines, C-reactive protein (CRP)), gut permeability (endocab, lactulose-mannitol ratio), enterocyte mass (citrulline) and general nutritional status (branched-chain amino acids (BCAA), insulin-like growth factor) in a group of 804 children in two Sub-Saharan countries. We correlated these markers with each other and with anemia in stunted and non-stunted children. AAT and calprotectin, CRP and citrulline and citrulline and BCAA correlated with each other. Furthermore, BCAA, citrulline, ferritin, fecal calprotectin and CRP levels were correlated with hemoglobin levels. Our results show that while several of the biomarkers are associated with anemia, there is little correlation between the different biomarkers. Better biomarkers and a better definition of EED are thus urgently needed.