Environmental Enteric Dysfunction in Children

Campylobacter infection of young children in Colombia and its impact on the gastrointestinal environment

Campylobacter infections are a leading cause of bacterial-derived gastroenteritis worldwide with particularly profound impacts on pediatric patients in low-and-middle income countries. It remains unclear how Campylobacter impacts these hosts, though it is becoming increasingly evident that it is a multifactorial process that depends on the host immune response, the gastrointestinal microbiota, various bacterial factors, and host nutritional status. Since these factors likely vary between adult and pediatric patients in different regions of the world, it is important that studies define these attributes in well characterized clinical cohorts in diverse settings. In this study, we analyzed the fecal microbiota and the metabolomic and micronutrient profiles of asymptomatic and symptomatic pediatric patients in Colombia that were either infected or uninfected with Campylobacter during a case-controlled study on acute diarrheal disease. Here, we report that the microbiome of Campylobacter- infected children only changed in their abundance of Campylobacter spp. despite the inclusion of children with or without diarrhea. In addition to increased Campylobacter, computational models were used to identify fecal metabolites that were associated with Campylobacter infection and found that glucose-6-phosphate and homovanillic acid were the strongest predictors of infection in these pediatric patients, which suggest that colonocyte metabolism are impacted during infection. Despite changes to the fecal metabolome, the concentrations of intestinal minerals and trace elements were not significantly impacted by Campylobacter infection, but were elevated in uninfected children with diarrhea.

Importance

Gastrointestinal infection with pathogenic Campylobacter species has long been recognized as a significant cause of human morbidity. Recently, it has been observed that pediatric populations in low-and-middle income countries are uniquely impacted by these organisms in that infected children can be persistently colonized, develop enteric dysfunction, and exhibit reduced development and growth. While the association of Campylobacter species with these long-term effects continues to emerge, the impact of infection on the gastrointestinal environment of these children remains uncharacterized. To address this knowledge gap, our group leveraged clinical samples collected during a previous study on gastrointestinal infections in pediatric patients to examine the fecal microbiota, metabolome, and micronutrient profiles of those infected with Campylobacter species, and found that the metabolome was impacted in a way that suggests gastrointestinal cell metabolism is affected during infection, which is some of the first data indicating how gastrointestinal health in these patients may be affected.

Colonization during a key developmental window reveals microbiota-dependent shifts in growth and immunity during undernutrition

BACKGROUND

Childhood undernutrition is a major global health challenge with devastating lifelong consequences. Linear growth stunting due to undernutrition has been linked to poor health outcomes, and mothers who experience growth stunting in childhood are more likely to give birth to stunted children later in life. Based on these findings, we hypothesized that intergenerational colonization of mice with microbiota from human donors with undernutrition may recapitulate certain immune and growth changes observed in this disorder.

RESULTS

To test this hypothesis, we developed a gnotobiotic murine model of undernutrition using microbiota from human infants with healthy or stunted growth trajectories. Intergenerational colonization with microbiota derived from children with growth stunting lead to less linear growth and the development of immune features of undernutrition and enteropathy, including intestinal villus blunting, lower liver IGF-1 and accumulation of intraepithelial lymphocytes and plasma cells in the small intestine. In contrast, colonization after weaning lead to fewer host phenotypic changes between these distinct microbial communities.

CONCLUSIONS

These results are broadly consistent with previous findings demonstrating that exposure of the immune system to microbial products during the weaning phase is a critical determinant of later life immune function. Overall, our results suggest intergenerational colonization with human microbiota samples is a useful approach with which to investigate microbiota-dependent changes in growth and immunity in early life. Murine models that capture the intergenerational and multifactorial nature of undernutrition are critical to understanding the underlying biology of this disorder. Video Abstract.

Modulating the early-life gut microbiota using pro-, pre-, and synbiotics to improve gut health, child development, and growth

In children exposed to poor hygiene and sanitation, invasion of the gut by pathogenic microbes can result in a subclinical enteropathy termed "environmental enteric dysfunction" (EED) that contributes to undernutrition, growth faltering, and impaired organ development. EED may already be present by age 6-12 weeks; therefore, interventions that can be started early in life, and used alongside breastfeeding, are needed to prevent or ameliorate EED. A healthy gut microbiota is critical for intestinal development and repair, nutrient digestion and absorption, and resisting colonization or overgrowth by pathogens. However, its development can be impaired by several environmental factors. Dietary supplementation with pro-, pre-, or synbiotics may be a pragmatic and safe means of building the resilience of the developing gut microbiota against adverse environmental factors, thereby preventing EED.

Harnessing the power of probiotics to enhance neuroplasticity for neurodevelopment and cognitive function in stunting: a comprehensive review

BACKGROUND

Stunting become a global concern because it's not only affecting physical stature, but also affecting on neurodevelopment and cognitive function. These impacts are resulting in long-term consequences especially for human resources, such as poor-quality labor, decreased productivity due to decreasing of health quality, including immunity and cognitive aspect.

DISCUSSION

This comprehensive review found that based on many studies, there is an altered gut microbiota, or dysbiosis, in stunted children, causing the impairment of brain development through Microbiota-Gut Brain Axis (MGB Axis) mechanism. The administration of probiotics has been known affect MGBA by improving the physical and chemical gut barrier integrity, producing antimicrobial substance to inhibit pathogen, and recovering the healthy gut microbiota. Probiotics, along with healthy gut microbiota, produce SCFAs which have various positive impact on CNS, such as increase neurogenesis, support the development and function of microglia, reduce inflammatory signaling, improve the Blood Brain Barrier's (BBB's) integrity, produce neurotropic factors (e.g. BDNF, GDNF), and promote the formation of new synapse. Probiotics also could induce the production of IGF-1 by intestinal epithelial cells, which functioned as growth factor of multiple body tissues and resulted in improvement of linear growth as well as brain development.

CONCLUSION

These properties of probiotics made it become the promising and feasible new treatment approach for stunting. But since most of the studies in this field are conducted in animal models, it is necessary to translate animal data into human models and do additional study to identify the numerous components in the MGB axis and the effect of probiotics on human.

Effect of a Homestead Food Production and Food Hygiene Intervention on Biomarkers of Environmental Enteric Dysfunction in Children Younger Than 24 Months in Rural Bangladesh: A Cluster-Randomized Controlled Trial

Poor sanitation and hygiene practices and inadequate diets can contribute to environmental enteric dysfunction (EED). We evaluated the impact of a combined homestead food production and food hygiene intervention on EED biomarkers in young children in rural Bangladesh. The analysis was conducted within the Food and Agricultural Approaches to Reducing Malnutrition (FAARM) cluster-randomized trial in Sylhet, Bangladesh. The FAARM trial enrolled 2,705 married women and their children younger than 3 years of age in 96 settlements (geographic clusters): 48 intervention and 48 control. The 3-year intervention (2015-2018) included training on gardening, poultry rearing, and improved nutrition practices and was supplemented by an 8-month food hygiene behavior change component, implemented from mid-2017. We analyzed data on 574 children age 0 to 24 months with multilevel linear regression. We assessed fecal myeloperoxidase (MPO), neopterin (NEO), and alpha-1-antitrypsin (AAT) as biomarkers of EED, and serum C-reactive protein (CRP) and alpha-1-acid glycoprotein (AGP) as biomarkers of systemic inflammation, using ELISA. There was no intervention effect on NEO, AAT, CRP, and AGP concentrations, but, surprisingly, MPO levels were increased in children of the intervention group (0.11 log ng/mL; 95% CI, 0.001-0.22). This increase was greater with increasing child age and among intervention households with poultry that were not kept in a shed. A combined homestead food production and food hygiene intervention did not decrease EED in children in our study setting. Small-scale poultry rearing promoted by the intervention might be a risk factor for EED.

Prevalence and Load of the Campylobacter Genus in Infants and Associated Household Contacts in Rural Eastern Ethiopia: a Longitudinal Study from the Campylobacter Genomics and Environmental Enteric Dysfunction (CAGED) Project

In our previous cross-sectional study, multiple species of Campylobacter were detected (88%) in stool samples from children (12 to 14 months of age) in rural eastern Ethiopia. This study assessed the temporal fecal carriage of Campylobacter in infants and identified putative reservoirs associated with these infections in infants from the same region. The prevalence and load of Campylobacter were determined using genus-specific real-time PCR. Stool samples from 106 infants (n = 1,073) were collected monthly from birth until 376 days of age (DOA). Human stool samples (mothers and siblings), livestock feces (cattle, chickens, goats, and sheep), and environmental samples (soil and drinking water) from the 106 households were collected twice per household (n = 1,644). Campylobacter was most prevalent in livestock feces (goats, 99%; sheep, 98%; cattle, 99%; chickens, 93%), followed by human stool samples (siblings, 91%; mothers, 83%; infants, 64%) and environmental samples (soil, 58%; drinking water, 43%). The prevalence of Campylobacter in infant stool samples significantly increased with age, from 30% at 27 DOA to 89% at 360 DOA (1% increase/day in the odds of being colonized) (P < 0.001). The Campylobacter load increased linearly (P < 0.001) with age from 2.95 logs at 25 DOA to 4.13 logs at 360 DOA. Within a household, the Campylobacter load in infant stool samples was positively correlated with the load in mother stool samples (r2 = 0.18) and soil collected inside the house (r2 = 0.36), which were in turn both correlated with Campylobacter loads in chicken and cattle feces (0.60 < r2 < 0.63) (P < 0.01). In conclusion, a high proportion of infants are infected with Campylobacter in eastern Ethiopia, and contact with the mother and contaminated soil may be associated with early infections. IMPORTANCE A high Campylobacter prevalence during early childhood has been associated with environmental enteric dysfunction (EED) and stunting, especially in low-resource settings. Our previous study demonstrated that Campylobacter was frequently found (88%) in children from eastern Ethiopia; however, little is known about potential Campylobacter reservoirs and transmission pathways leading to infection of infants by Campylobacter during early growth. In the longitudinal study presented here, Campylobacter was frequently detected in infants within the 106 surveyed households from eastern Ethiopia, and the prevalence was age dependent. Furthermore, preliminary analyses highlighted the potential role of the mother, soil, and livestock in the transmission of Campylobacter to the infant. Further work will explore the species and genetic composition of Campylobacter in infants and putative reservoirs using PCR and whole-genome and metagenomic sequencing. The findings from these studies can lead to the development of interventions to minimize the risk of transmission of Campylobacter to infants and, potentially, EED and stunting.

Colonization during a key developmental window reveals microbiota-dependent shifts in growth and immunity during undernutrition

Childhood undernutrition is a major global health challenge with devastating lifelong consequences. Linear growth stunting due to undernutrition has been linked to poor outcomes, and mothers who experience stunting are more likely to give birth to stunted children. Murine models that capture the intergenerational and multifactorial nature of undernutrition are critical to understanding the underlying biology of this disorder. Here we report a gnotobiotic mouse model of undernutrition using microbiota from human infants with healthy or stunted growth trajectories. Intergenerational transmission of microbiota from parents to offspring leads to the development of growth and immune features of undernutrition and enteropathy, including reduced linear growth, intestinal villus blunting and accumulation of intraepithelial lymphocytes. In contrast, colonization after weaning reduces sensitivity to detect changes driven by distinct microbial communities. Overall, these results suggest intergenerational colonization is a useful approach with which to investigate microbiota-dependent growth and immunity in early life.

Child-Owned Poultry Intervention Effects on Hemoglobin, Anemia, Concurrent Anemia and Stunting, and Morbidity Status of Young Children in Southern Ethiopia: A Cluster Randomized Controlled Community Trial

Cereal-based diets contribute to anemia in Ethiopian children. Eggs have nutrients to boost hemoglobin levels as well as counter concurrent anemia and stunting (CAS) and morbidity status. A community trial, targeting 6-18 months old children, was conducted in Halaba. Two clusters were randomly selected and allocated to intervention (N = 122) and control (N = 121) arms. Intervention group (IG) children received egg-laying hens with caging in a cultural ceremony declaring child ownership of the chickens. Parents promised to feed eggs to the child. Health and agriculture extension workers promoted egg feeding, poultry husbandry, and sanitation to IG families. Control group (CG) had standard health and agriculture education. At baseline, groups were not different by hemoglobin, anemia, CAS, and morbidity status. Mean hemoglobin was 11.0 mg/dl and anemia prevalence was 41.6%. About 11.9% of children had CAS and 52.3% were sick. Using generalized estimating equations, the intervention increased hemoglobin by 0.53 g/dl (ß:0.53; p < 0.001; 95%CI: 0.28-0.79). IG children were 64% (p < 0.001; odds ratio [OR]:0.36; 95%CI: 0.24-0.54) and 57% (p = 0.007; OR: 0.43; 95%CI: 0.21-0.73) less likely to be anemic and have CAS, respectively, than CG, with no difference in morbidity. Child-owned poultry intervention is recommended in settings where anemia is high and animal-source food intake is low.

Environmental enteric dysfunction: gut and microbiota adaptation in pregnancy and infancy

Environmental enteric dysfunction (EED) is a subclinical syndrome of intestinal inflammation, malabsorption and barrier disruption that is highly prevalent in low- and middle-income countries in which poverty, food insecurity and frequent exposure to enteric pathogens impair growth, immunity and neurodevelopment in children. In this Review, we discuss advances in our understanding of EED, intestinal adaptation and the gut microbiome over the 'first 1,000 days' of life, spanning pregnancy and early childhood. Data on maternal EED are emerging, and they mirror earlier findings of increased risks for preterm birth and fetal growth restriction in mothers with either active inflammatory bowel disease or coeliac disease. The intense metabolic demands of pregnancy and lactation drive gut adaptation, including dramatic changes in the composition, function and mother-to-child transmission of the gut microbiota. We urgently need to elucidate the mechanisms by which EED undermines these critical processes so that we can improve global strategies to prevent and reverse intergenerational cycles of undernutrition.

ApoE Mimetic Peptides to Improve the Vicious Cycle of Malnutrition and Enteric Infections by Targeting the Intestinal and Blood-Brain Barriers

Apolipoprotein E (apoE) mimetic peptides are engineered fragments of the native apoE protein’s LDL-receptor binding site that improve the outcomes following a brain injury and intestinal inflammation in a variety of models. The vicious cycle of enteric infections and malnutrition is closely related to environmental-driven enteric dysfunction early in life, and such chronic inflammatory conditions may blunt the developmental trajectories of children with worrisome and often irreversible physical and cognitive faltering. This window of time for microbiota maturation and brain plasticity is key to protecting cognitive domains, brain health, and achieving optimal/full developmental potential. This review summarizes the potential role of promising apoE mimetic peptides to improve the function of the gut-brain axis, including targeting the blood-brain barrier in children afflicted with malnutrition and enteric infections.

Smad7 as a positive regulator of intestinal inflammatory diseases

In physiological conditions, the human gut contains more immune cells than the rest of the body, but no overt tissue damage occurs, because several regulatory mechanisms control the activity of such cells thus preventing excessive and detrimental responses. One such mechanism relies on the action of transforming growth factor (TGF)-β1, a cytokine that targets both epithelial cells and many immune cell types. Loss of TGF-β1 function leads to intestinal pathology in both mice and humans. For instance, disruption of TGF-β1 signaling characterizes the destructive immune-inflammatory response in patients with Crohn's disease and patients with ulcerative colitis, the major human inflammatory bowel disease (IBD) entities. In these pathologies, the defective TGF-β1-mediated anti-inflammatory response is associated with elevated intestinal levels of Smad7, an antagonist of TGF-β1 signaling. Consistently, knockdown of Smad7 restores TGF-β1 function thereby attenuating intestinal inflammation in patients with IBD as well as in mice with IBD-like colitis. Up-regulation of Smad7 and reduced TGF-β1 signaling occurs also in necrotizing enterocolitis, environmental enteropathy, refractory celiac disease, and cytomegalovirus-induced colitis. In this article, we review the available data supporting the pathogenic role of Smad7 in the gastrointestinal tract and discuss whether and how targeting Smad7 can help attenuate detrimental immuno-inflammatory responses in the gut.

Animal-source foods as a suitable complementary food for improved physical growth in 6 to 24-month-old children in low- and middle-income countries: a systematic review and meta-analysis of randomised controlled trials

Although animal-source foods are suitable complementary food for child growth in low- and middle-income countries (LMICs), their efficacy is still under discussion. This systematic review and meta-analysis was done to investigate the suitability of animal-source foods intake on child physical growth in LMICs. A systematic literature search was done using electronic databases and scanning the reference list of included studies, previous meta-analysis and systematic reviews. Paper selection was based on the PICO (ST) criteria. Papers were selected if based on 6 to 24-month-old children, if they were randomised controlled trials evaluating the effect of complementary animal-based food supplementation of any natural origin, if reporting at least a measure of body size and published after 2000. The PRISMA guidelines for reporting systematic review was followed in the paper selection. Fourteen papers were included in the systematic review and eight were considered for the meta-analysis. Animal-based food supplementation resulted in a higher length-for-age LAZ and weight-for-age (WAZ) Z-scores compared with the control group with random effect size of 0·15 (95 % CI 0·02, 0·27) and 0·20 (95 % CI 0·03, 0·36), respectively. Results were confirmed after influence analyses, and publication bias resulted as negligible. An increased effect on LAZ and WAZ was observed when the food supplementation was based on egg with effect size of 0·31 (95 % CI = -0·03, 0·64) and 0·36 (95 % CI = -0·03, 0·75), respectively. Animal-source foods are a suitable complementary food to improve growth in 6 to 24-month-old children in LMICs.

Effect of a Child-Owned Poultry Intervention Providing Eggs on Nutrition Status and Motor Skills of Young Children in Southern Ethiopia: A Cluster Randomized and Controlled Community Trial

Eggs are highly nutritious foods, yet intake by children in Ethiopia is low. We hypothesized that a nutrition-sensitive poultry intervention improves nutritional status of children 6-18 months using a 6-month cluster randomized controlled community trial. Intervention group (IG) children received a gift of two egg-laying hens in a ceremony where children's ownership of the chickens was declared by community leaders. Parents promised to add more hens and feed the owner-child one-egg-a-day. Trained community workers reinforced egg feeding, environmental sanitation and poultry husbandry. Control group (CG) mothers received usual nutrition education on child feeding. At baseline 29.6% of children were stunted, 19.4% underweight and 8.6% wasted. Egg consumption significantly increased only in IG, at 6 months. The intervention increased weight-for-age and weight-for-height z-scores by 0.38 (95% CI = 0.13-0.63) and 0.43 (95% CI = 0.21-0.64), respectively. Binary logit model indicated IG children were 54% (Odds ratio [OR] = 0.46; 95% CI = 0.26-0.84) and 42% (OR = 0.58; 95% CI = 0.37-0.91) less likely to be underweight and stunted, respectively, compared to CG. IG children attained the milestone of running (p = 0.022; AHR = 1.43; 95% CI = 1.05-1.95), kicking a ball (p = 0.027; AHR = 1.39; 95% CI = 1.04-1.87) and throwing a ball (p = 0.045; AHR = 1.37; 95% CI = 1.01-1.86) earlier than CG. This nutrition-sensitive child-owned poultry approach should be implemented where animal-source food intake is low.

Zinc Kinetics Correlate With Length-for-Age z Scores in Bangladeshi Infants

OBJECTIVES

Stunting [length-for-age z score (LAZ) &lt;-2] has multiple causes and is prevalent in areas with low dietary zinc (Zn) intake. Zinc kinetics from non-stunted infants were used in a published model for predicting linear growth; here, we directly measure zinc kinetics in stunted infants.

METHODS

Zinc kinetics were determined in 9-month-old Bangladeshi infants (n = 10), who were non-wasted [weight-for-length z score (WLZ) &gt; -2], ranging in LAZ from -2.9 to -0.43. Stable isotopes were administered 2 hours after a meal as oral ( 70 Zn) and intravenous ( 67 Zn) tracers. After isotope administration, blood was sampled within 5 hours and all urine and feces were collected for 24 hours. Urine was sampled twice-daily out to 9 days. Data were analyzed by compartmental modeling. Daily zinc intake was estimated by the model as the sum of zinc used for growth plus that lost via urine and feces. Zinc absorbed (the amount required to maintain steady state) was the sum of zinc used for growth plus urine and endogenous fecal excretions.

RESULTS

The LAZ score correlated with serum zinc concentration ( R = 0.77, P = 0.001), urinary zinc excretion ( R = 0.66, P = 0.010), and fractional zinc absorption from calculated daily intake ( R = 0.58, P = 0.030). In stunted infants (n = 8), the amount of zinc absorbed did not increase with calculated zinc intake unlike published values for non-stunted infants.

CONCLUSIONS

Zinc kinetics in Bangladeshi infants correlate with LAZ and show that malabsorption of supplemental sources of zinc may occur in stunted infants.

Investigating the Impact of Moringa oleifera Supplemented to Kenyan Breastfeeding Mothers on Maternal and Infant Health: A Cluster Randomized Single-Blinded Controlled Pilot Trial Protocol

Undernutrition contributes to up to 45% of deaths globally in children <5 years, with an optimal time for intervention before 24 months of age. Breastmilk microbiome helps establish the infant intestinal microbiome and impacts infant intestinal and nutritional health. Inadequacies in breastmilk composition such as low vitamin A contribute to infant nutrient deficiencies. Changes in milk fatty acid composition (reduced saturated and increased unsaturated fatty acids) may reduce susceptibility to enteric infection and increase protective intestinal bacteria. Moringa oleifera leaves (moringa) provide high nutrient concentrations (including protein, iron, vitamin A) and increase milk production; this may enhance breastmilk quantity and quality and improve infant health.

Objective

To investigate the role of moringa supplementation to improve maternal and infant nutritional and intestinal health via changes in maternal milk quantity and quality.

Methods

Fifty mother-infant pairs exclusively breastfeeding will be enrolled in a single-blinded randomized controlled trial in Kombewa County Hospital and Chulaimbo SubCounty Hospital, Kisumu, Kenya.

Intervention

Dietary Supplementation of 20 g of Moringa oleifera leaf powder divided twice daily in corn porridge consumed daily for 3 months while control comparator will receive porridge daily for 3 months.

Outcomes

Change in infant growth and maternal milk output (primary); maternal and infant vitamin A and iron status, changes in infant and maternal intestinal health (secondary).

Participating Centers

Pamoja Community Based Organization, Kombewa Sub-County Hospital, and Chulaimbo Sub-County Hospital.

Infection With Escherichia Coli Pathotypes Is Associated With Biomarkers of Gut Enteropathy and Nutritional Status Among Malnourished Children in Bangladesh

Escherichia coli (E. coli) pathotypes are the most common cause of diarrhea, especially in developing countries. Environmental Enteric Dysfunction (EED) is presumed to be the result of infection with one or more pathotypes and can affect intestinal health and childhood growth. We sought to investigate the association of E. coli pathotypes infection with biomarkers of EED and nutritional status among slum-dwelling malnourished children in Bangladesh. This study comprised a total of 1050 stunted and at risk of stunting children. TaqMan Array Card assays were used to determine the presence of E. coli pathotypes in feces. Prevalence of infection with EAEC was highest (68.8%) in this cohort of children, followed by EPEC (55.9%), ETEC (44%), Shigella/EIEC (19.4%) and STEC (3.2%). The levels of myeloperoxidase and calprotectin were significantly higher in EAEC (P=0.02 and P=0.04), EPEC (P=0.02 and P=0.03) and Shigella/EIEC (P=0.05 and P=0.02) positive participants while, only calprotectin was significantly higher in ETEC (P=0.01) positive participants. Reg1B was significantly higher in participants with EAEC (P=0.004) while, neopterin levels were significantly lower in ETEC (P=0.003) and Shigella/EIEC (P=0.003) positive cases. A significant positive relationship was observed between EAEC and fecal levels of Reg1B (β = 0.28; 95% CI = 0.12, 0.43; p-value<0.001). Besides, ETEC was found to be positively and significantly associated with the levels of calprotectin (β = 0.14; 95 percent CI = 0.01, 0.26; p-value=0.037) and negatively with neopterin (β = -0.16; 95% CI = -0.30, -0.02; p-value=0.021). On the other hand, infection with EPEC was found to be negatively associated with length-for-age (β = -0.12; 95% CI = -0.22, -0.03; p-value=0.011) and weight-for-age (β = -0.11; 95% CI = -0.22, -0.01; p-value=0.037). The study findings suggest that infection with certain E. coli pathotypes (EAEC and ETEC) influences gut health and EPEC is associated with linear growth and underweight in Bangladeshi children.

Associations of bacterial enteropathogens with systemic inflammation, iron deficiency, and anemia in preschool-age children in southern Ghana

Anemia remains a pervasive public health problem among preschool-age children in Ghana. Recent analyses have found that anemia in Ghanaian children, particularly in Southern regions, is largely attributable to infectious causes, rather than nutritional factors. Infections with enteropathogens can reduce iron absorption and increase systemic inflammation, but few studies have examined direct links between enteropathogens and anemia. This study investigated associations between detection of individual bacterial enteropathogens and systemic inflammation, iron deficiency, and anemia among 6- to 59-month-old children in Greater Accra, Ghana. Serum samples were analyzed from a cross-sectional sample of 262 children for concentrations of hemoglobin (Hb), biomarkers of systemic inflammation [C-reactive protein (CRP) and α-1-acid glycoprotein (AGP)], and biomarkers of iron status [serum ferritin (SF) and serum transferrin receptor (sTfR)]. Stool samples were analyzed for ten bacterial enteropathogens using qPCR. We estimated associations between presence of each enteropathogen and elevated systemic inflammation (CRP > 5 mg/L and AGP > 1 g/L), iron deficiency (SF < 12 μg/L and sTfR > 8.3 mg/L) and anemia (Hb < 110 g/L). Enteropathogens were detected in 87% of children’s stool despite a low prevalence of diarrhea (6.5%). Almost half (46%) of children had anemia while one-quarter (24%) had iron deficiency (low SF). Despite finding no associations with illness symptoms, Campylobacter jejuni/coli detection was strongly associated with elevated CRP [Odds Ratio (95% CI): 3.49 (1.45, 8.41)] and elevated AGP [4.27 (1.85, 9.84)]. Of the pathogens examined, only enteroinvasive Escherichia coli/Shigella spp. (EIEC/Shigella) was associated with iron deficiency, and enteroaggregative Escherichia coli (EAEC) [1.69 (1.01, 2.84)] and EIEC/Shigella [2.34 (1.15, 4.76)] were associated with anemia. These results suggest that certain enteroinvasive pathogenic bacteria may contribute to child anemia. Reducing exposure to enteropathogens through improved water, sanitation, and hygiene practices may help reduce the burden of anemia in young Ghanaian children.

Association between Pathogenic Variants of Diarrheagenic Escherichia coli and Growth in Children under 5 Years of Age in the Global Enteric Multicenter Study

There is a lack of information highlighting associations between different pathogenic variants of diarrheagenic Escherichia coli and childhood growth. Pathogenic variants of E. coli from stool samples, collected from 22,567 children enrolled in the Global Enteric Multicenter Study from December 2007 to March 2011, were detected by real-time polymerase chain reaction. We estimated the associations of different pathogenic variants of diarrheagenic E. coli with child growth. The association between an explanatory variable and the outcome variable was assessed using multiple linear regression, where the dependent variables were height-for-age, weight-for-age, and weight-for-height z-scores, and the independent variable was the presence of different pathogenic variants of diarrheagenic E. coli. After adjusting for potential covariates, such as age, gender, diarrhea, breastfeeding status, mother’s education, number of under-5 children, handwashing practice, handwashing material, source of drinking water, wealth index, available toilet facility, copathogens, comorbidity, time, and study site, the multivariable model identified a negative association between different pathogenic variants of diarrheagenic E. coli and child growth. Our analyses may provide the cornerstone for prospective epidemiologic investigation for the development of preventive measures for diarrheagenic E. coli and combat childhood undernutrition.

Association between vaccine preventable diseases in children and improved sanitation following a nationwide sanitation campaign in India: an ecological analysis

OBJECTIVE

Persistent exposure to faecal pathogens due to open defecation may cause environmental enteropathy that, in turn, may lead to undernutrition and vaccine failure in under 5-year-old (u5) children. The Swachh Bharat Mission (SBM) programme in India, launched in 2014, aimed to construct toilets for every household nationwide and reduce open defecation. This programme, if successful, had the potential to reduce the burden of four vaccine preventable diseases (VPDs): diphtheria, pertussis, tetanus and measles. We examine whether increased household toilet availability in Indian districts following SBM corresponds with a reduction in diphtheria, pertussis, tetanus and measles in u5 children.

DESIGN

Observational, ecological study.

SETTING

532 districts in 28 Indian states, from 2013 to 2016.

PRIMARY OUTCOME AND EXPOSURE

We retrieved data on district-level change in the annual incidence (per 1000 u5 children) of four VPDs, from 2013 (pre-SBM) to 2016 (post-SBM). We obtained data on our exposure, the change in the percentage of households with toilets (per district), from three large national surveys conducted in 2013 and 2016. We used linear regression analysis, which controlled for change over time in socioeconomic factors, health system-related covariates and pre-SBM annual incidence of VPDs.

RESULTS

A one percentage point increase in households with toilets corresponds with 0.33 fewer measle cases per 1000 u5 children in a district (coefficient: -0.33, 95% CI -0.0641 to -0.014; p<0.05). About 12% of this association is mediated by a reduction in u5 stunting. We observe no relation of the exposure with diphtheria, pertussis or tetanus. Findings remain robust to sensitivity analyses.

CONCLUSION

Rapid improvements in ambient sanitation through increased toilet availability correspond with a reduction in the annual incidence of measles in u5 children. We encourage replication of findings and further research to identify potential pathways by which SBM may reduce measle burden in u5 children.

Effect of Community-Initiated Kangaroo Mother Care on Fecal Biomarkers of Gut Function in Low Birth Weight Infants in North India: A Randomized Clinical Trial

This individually randomized trial was conducted to estimate the effect of promoting community-initiated Kangaroo Mother Care (ciKMC) in low birth weight (LBW) infants on gut inflammation and permeability. Participants included 200 stable LBW infants (weighing 1,500-2,250 g) in North India enrolled between May and October 2017. The ciKMC intervention included promotion and support of continuous skin-to-skin contact and exclusive breastfeeding through home visits. The mothers in the intervention arm were supported to practice ciKMC until 28 days after birth, i.e., the neonatal period, or till the baby wriggled out of KMC position, if earlier. Infant stool specimens were collected during the first week of birth, and within 1 week after end of the neonatal period. Concentrations of fecal neopterin (nmol/L), myeloperoxidase (ng/mL), and alpha-1-antitrypsin (μg/mL) were determined using ELISA, and composite enteric enteropathy (EE) score at the end of the neonatal period was calculated by principal component analysis. We did not find any substantial difference in means between the ciKMC and control arm infants in the log-transformed values of neopterin (0.03; 95% CI -0.15 to 0.21), myeloperoxidase (0.28; 95% CI -0.05 to 0.61) and alpha-1-antitrypsin (0.02; 95% CI -0.30 to 0.34). The mean (SD) composite EE score was 13.6 (7.5) in the ciKMC and 12.4 (8.3) in the control arm infants, and the adjusted difference in means was, 0.4 (95% CI -1.8 to 2.7). Our findings suggest that the promotion of ciKMC did not affect gut inflammation and permeability in our target population of LBW infants in North India.

Toll-Like Receptor-Induced Immune Responses During Early Childhood and Their Associations With Clinical Outcomes Following Acute Illness Among Infants in Sub-Saharan Africa

Severely ill children in low- and middle-income countries (LMICs) experience high rates of mortality from a broad range of infectious diseases, with the risk of infection-related death compounded by co-existing undernutrition. How undernutrition and acute illness impact immune responses in young children in LMICs remains understudied, and it is unclear what aspects of immunity are compromised in this highly vulnerable population. To address this knowledge gap, we profiled longitudinal whole blood cytokine responses to Toll-like receptor (TLR) ligands among severely ill children (n=63; 2-23 months old) with varied nutritional backgrounds, enrolled in the CHAIN Network cohort from Kampala, Uganda, and Kilifi, Kenya, and compared these responses to similar-aged well children in local communities (n=41). Cytokine responses to ligands for TLR-4 and TLR-7/8, as well as Staphylococcus enterotoxin B (SEB), demonstrated transient impairment in T cell function among acutely ill children, whereas innate cytokine responses were exaggerated during both acute illness and following clinical recovery. Nutritional status was associated with the magnitude of cytokine responses in all stimulated conditions. Among children who died following hospital discharge or required hospital re-admission, exaggerated production of interleukin-7 (IL-7) to all stimulation conditions, as well as leukopenia with reduced lymphocyte and monocyte counts, were observed. Overall, our findings demonstrate exaggerated innate immune responses to pathogen-associated molecules among acutely ill young children that persist during recovery. Heightened innate immune responses to TLR ligands may contribute to chronic systemic inflammation and dysregulated responses to subsequent infectious challenges. Further delineating mechanisms of innate immune dysregulation in this population should be prioritized to identify novel interventions that promote immune homeostasis and improve outcomes.

Site specific incidence rate of virulence related genes of enteroaggregative Escherichia coli and association with enteric inflammation and growth in children

There is a lack of information highlighting the possible association between strain carrying genes of enteroaggregative Escherichia coli (EAEC) and environmental enteric dysfunction (EED) and on linear growth during childhood. Strain carrying genes of EAEC from stool samples collected from 1705 children enrolled in the MAL-ED birth cohort were detected by TaqMan Array Cards. We measured site-specific incidence rate by using Poisson regression models, identified the risk factors and estimated the associations of strain carrying genes of EAEC with the composite EED score and linear growth at 24 months of age. Overall highest incidence rate (43.3%) was found among children having infection with the aggR gene, which was the greatest in Tanzania (56.7%). Low maternal education, lack of improved floor, and ownership of domestic cattle were found to be risk factors for EAEC infection. In the multivariate models, after adjusting the potential covariates, strain carrying genes of EAEC showed strong positive associations with the EED scores and with poor linear growth at 24 months of age. Our analyses may lay the cornerstone for a prospective epidemiologic investigation for a potential vaccine development aimed at reducing the burden of EAEC infections and combat childhood malnutrition.

Serum Biomarkers of Environmental Enteric Dysfunction and Growth Perspective in Egyptian Children

BACKGROUND: Environmental enteric dysfunction (EED) is a chronic subclinical condition, contributed to limited sources and poor countries. EED pathology is concerned with small intestine structure and function, which affect the macronutrients and micronutrients absorption with consequent growth faltering. AIM: This study aimed to evaluate some serum biomarkers involved in EED and determine their association with stunting and faltering growth in children; zonulin, endotoxin core antibody (EndoCAb), high-sensitive C-reactive protein (hsCRP), alpha-1-acid glycoprotein (AGP), and tumor necrosis factor (TNF), serum iron, and Vitamins A and D. PATIENTS AND METHODS: This case–control study enrolled 105 children aged from 1 to 10 years old, having weight-for-age z-scores and height-for-age z-scores (WAZ or HAZ) ranging from −1.5 to −2. They were compared with control group consisted of 100 children having WAZ or HAZ > −1 of matched age and sex. Assessment of serum markers levels of enteric dysfunction (zonulin and EndoCAb), markers of systemic inflammation (Hs CRP and AGP), along with serum micronutrients (vitamin A, vitamin D and iron) in children with malnutrition in comparison to controls. RESULTS: There was a highly significant decrease as regarding the anthropometric measurements; weight, height, BMI, and arm circumference. Moreover, significant increase in serum zonulin, EndoCAb, HsCRP, and AGP and highly significant decrease of serum Vitamin D and iron in cases group as compared to control group. Height Z score showed negative correlation with zonulin, HsCRP, and AGP and positive correlation with Vitamin D. Weight Z score showed negative correlation with zonulin, HsCRP, and AGP and positive correlation with Vitamin D and Vitamin A. Regression analysis noted increase of zonulin and α1AGP as high associative markers with height Z score affection, however, increase of zonulin was high associative markers with weight Z score affection. CONCLUSION: Faltering growth is associated with elevated serum systemic markers of intestinal inflammation (HsCRP and α1AGP). EED may be a cause of faltering growth.

Combating Childhood Infections in LMICs: evaluating the contribution of Big Data Big data, biomarkers and proteomics: informing childhood diarrhoeal disease management in Low- and Middle-Income Countries

Despite efforts to reduce the global burden of childhood diarrhoea, 50% of all cases globally occur in children under five years in Low–Income and Middle- Income Countries (LMICs) and knowledge gaps remain regarding the aetiological diagnosis, introduction of diarrhoeal vaccines, and the role of environmental enteric dysfunction and severe acute malnutrition. Biomarkers may assist in understanding disease processes, from diagnostics, to management of childhood diarrhoea and the sequelae to vaccine development. Proteomics has the potential to assist in the identification of new biomarkers to understand the processes in the development of childhood diarrhoea and to aid in developing new vaccines. Centralised repositories that enable mining of large data sets to better characterise risk factors, the proteome of both the patient and the different diarrhoeal pathogens, and the environment, could inform patient management and vaccine development, providing a systems biological approach to address the burden of childhood diarrhoea in LMICs.

Bile Acid Profiling Reveals Distinct Signatures in Undernourished Children with Environmental Enteric Dysfunction

BACKGROUND

Intestinal inflammation and malabsorption in environmental enteric dysfunction (EED) are associated with early childhood growth faltering in impoverished settings worldwide.

OBJECTIVES

The goal of this study was to identify candidate biomarkers associated with inflammation, EED histology, and as predictors of later growth outcomes by focusing on the liver-gut axis by investigating the bile acid metabolome.

METHODS

Undernourished rural Pakistani infants (n = 365) with weight-for-height Z score (WHZ) < -2 were followed up to the age of 24 mo and monitored for growth, infections, and EED. Well-nourished local children (n = 51) were controls, based on consistent WHZ > 0 and height-for-age Z score (HAZ) > -1 on 2 consecutive visits at 3 and 6 mo. Serum bile acid (sBA) profiles were measured by tandem MS at the ages of 3-6 and 9 mo and before nutritional intervention. Biopsies and duodenal aspirates were obtained following upper gastrointestinal endoscopy from a subset of children (n = 63) that responded poorly to nutritional intervention. BA composition in paired plasma and duodenal aspirates was compared based on the severity of EED histopathological scores and correlated to clinical and growth outcomes.

RESULTS

Remarkably, >70% of undernourished Pakistani infants displayed elevated sBA concentrations consistent with subclinical cholestasis. Serum glycocholic acid (GCA) correlated with linear growth faltering (HAZ, r = -0.252 and -0.295 at the age of 3-6 and 9 mo, respectively, P <0.001) and biomarkers of inflammation. The proportion of GCA positively correlated with EED severity for both plasma (rs = 0.324 P = 0.02) and duodenal aspirates (rs = 0.307 P = 0.06) in children with refractory wasting that underwent endoscopy, and the proportion of secondary BA was low in both undernourished and EED children.

CONCLUSIONS

Dysregulated bile acid metabolism is associated with growth faltering and EED severity in undernourished children. Restoration of intestinal BA homeostasis may offer a novel therapeutic target for undernutrition in children with EED. This trial was registered at clinicaltrials.gov as NCT03588013.

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.

Daily Rice Bran Consumption for 6 Months Influences Serum Glucagon-Like Peptide 2 and Metabolite Profiles without Differences in Trace Elements and Heavy Metals in Weaning Nicaraguan Infants at 12 Months of Age

BACKGROUND

Environmental enteric dysfunction (EED) is associated with chronic gut inflammation affecting nutrient absorption and development of children, primarily in low- and middle-income countries. Several studies have shown that rice bran (RB) supplementation provides nutrients and modulates gut inflammation, which may reduce risk for undernutrition.

OBJECTIVE

The aim was to evaluate the effect of daily RB dietary supplementation for 6 mo on serum biomarkers in weaning infants and associated changes in serum and stool metabolites.

METHODS

A 6-mo randomized-controlled dietary intervention was conducted in a cohort of weaning 6-mo-old infants in León, Nicaragua. Anthropometric indices were obtained at 6, 8, and 12 mo. Serum and stool ionomics and metabolomics were completed at the end of the 6-mo intervention using inductively coupled plasma MS and ultra-high performance LC-tandem MS. The ɑ1-acid glycoprotein, C-reactive protein, and glucagon-like peptide 2 (GLP-2) serum EED biomarkers were measured by ELISA.

RESULTS

Twenty-four infants in the control group and 23 in the RB group successfully completed the 6-mo dietary intervention with 90% dietary compliance. RB participants had higher concentrations of GLP-2 as compared with control participants at 12 mo [median (IQR): 743.53 (380.54) pg/mL vs. 592.50 (223.59) pg/mL; P = 0.04]. Metabolite profiles showed significant fold differences of 39 serum metabolites and 44 stool metabolites from infants consuming RB compared with control, and with significant metabolic pathway enrichment scores of 4.7 for the tryptophan metabolic pathway, 5.7 for polyamine metabolism, and 5.7 for the fatty acid/acylcholine metabolic pathway in the RB group. No differences were detected in serum and stool trace elements or heavy metals following daily RB intake for 6 mo.

CONCLUSIONS

RB consumption influences a suite of metabolites associated with growth promotion and development, while also supporting nutrient absorption as measured by changes in serum GLP-2 in Nicaraguan infants. This clinical trial was registered at https://clinicaltrials.gov as NCT02615886.

Diversity and dynamism of IgA-microbiota interactions

IgA mediates microbial homeostasis at the intestinal mucosa. Within the gut, IgA acts in a context-dependent manner to both prevent and promote bacterial colonization and to influence bacterial gene expression, thus providing exquisite control of the microbiota. IgA-microbiota interactions are highly diverse across individuals and populations, yet the factors driving this variation remain poorly understood. In this Review, we summarize evidence for the host, bacterial and environmental factors that influence IgA-microbiota interactions. Recent advances have helped to clarify the antigenic specificity and immune selection of intestinal IgA and have highlighted the importance of microbial glycan recognition. Furthermore, emerging evidence suggests that diet and nutrition play an important role in shaping IgA recognition of the microbiota. IgA-microbiota interactions are disrupted during both overnutrition and undernutrition and may be altered dynamically in response to diet, with potential implications for host health. We situate this research in the context of outstanding questions and future directions in order to better understand the fascinating paradigm of IgA-microbiota homeostasis.

Gene expression profiles compared in environmental and malnutrition enteropathy in Zambian children and adults

BACKGROUND

Environmental enteropathy (EE) contributes to growth failure in millions of children worldwide, but its relationship to clinical malnutrition has not been elucidated. We used RNA sequencing to compare duodenal biopsies from adults and children with EE, and from children with severe acute malnutrition (SAM), to define key features of these malnutrition-related enteropathies.

METHODS

RNA was extracted and sequenced from biopsies of children with SAM in hospital (n=27), children with non-responsive stunting in the community (n=30), and adults living in the same community (n=37) using an identical sequencing and analysis pipeline. Two biopsies each were profiled and differentially expressed genes (DEGs) were computed from the comparisons of the three groups. DEG lists from these comparisons were then subjected to analysis with CompBio software to assemble a holistic view of the biological landscape and IPA software to interrogate canonical pathways.

FINDINGS

Dysregulation was identified in goblet cell/mucin production and xenobiotic metabolism/detoxification for both cohorts of children, versus adults. Within the SAM cohort, substantially greater induction of immune response and barrier function, including NADPH oxidases was noted, concordant with broadly reduced expression of genes associated with the brush border and intestinal structure/transport/absorption. Interestingly, down regulation of genes associated with the hypothalamic-pituitary-adrenal axis was selectively observed within the cohort of children with stunting.

INTERPRETATION

Gene expression profiles in environmental enteropathy and severe acute malnutrition have similarities, but SAM has several distinct transcriptional features. The intestinal capacity to metabolise drugs and toxins in malnourished children requires further study.

FUNDING

Bill & Melinda Gates Foundation (OPP1066118).

Understanding the role of the gut in undernutrition: what can technology tell us?

Gut function remains largely underinvestigated in undernutrition, despite its critical role in essential nutrient digestion, absorption and assimilation. In areas of high enteropathogen burden, alterations in gut barrier function and subsequent inflammatory effects are observable but remain poorly characterised. Environmental enteropathy (EE)-a condition that affects both gut morphology and function and is characterised by blunted villi, inflammation and increased permeability-is thought to play a role in impaired linear growth (stunting) and severe acute malnutrition. However, the lack of tools to quantitatively characterise gut functional capacity has hampered both our understanding of gut pathogenesis in undernutrition and evaluation of gut-targeted therapies to accelerate nutritional recovery. Here we survey the technology landscape for potential solutions to improve assessment of gut function, focussing on devices that could be deployed at point-of-care in low-income and middle-income countries (LMICs). We assess the potential for technological innovation to assess gut morphology, function, barrier integrity and immune response in undernutrition, and highlight the approaches that are currently most suitable for deployment and development. This article focuses on EE and undernutrition in LMICs, but many of these technologies may also become useful in monitoring of other gut pathologies.

Artificial Intelligence-based Analytics for Diagnosis of Small Bowel Enteropathies and Black Box Feature Detection

OBJECTIVES

Striking histopathological overlap between distinct but related conditions poses a disease diagnostic challenge. There is a major clinical need to develop computational methods enabling clinicians to translate heterogeneous biomedical images into accurate and quantitative diagnostics. This need is particularly salient with small bowel enteropathies; environmental enteropathy (EE) and celiac disease (CD). We built upon our preliminary analysis by developing an artificial intelligence (AI)-based image analysis platform utilizing deep learning convolutional neural networks (CNNs) for these enteropathies.

METHODS

Data for the secondary analysis was obtained from three primary studies at different sites. The image analysis platform for EE and CD was developed using CNNs including one with multizoom architecture. Gradient-weighted class activation mappings (Grad-CAMs) were used to visualize the models' decision-making process for classifying each disease. A team of medical experts simultaneously reviewed the stain color normalized images done for bias reduction and Grad-CAMs to confirm structural preservation and biomedical relevance, respectively.

RESULTS

Four hundred and sixty-one high-resolution biopsy images from 150 children were acquired. Median age (interquartile range) was 37.5 (19.0-121.5) months with a roughly equal sex distribution; 77 males (51.3%). ResNet50 and shallow CNN demonstrated 98% and 96% case-detection accuracy, respectively, which increased to 98.3% with an ensemble. Grad-CAMs demonstrated models' ability to learn different microscopic morphological features for EE, CD, and controls.

CONCLUSIONS

Our AI-based image analysis platform demonstrated high classification accuracy for small bowel enteropathies which was capable of identifying biologically relevant microscopic features and emulating human pathologist decision-making process. Grad-CAMs illuminated the otherwise "black box" of deep learning in medicine, allowing for increased physician confidence in adopting these new technologies in clinical practice.

Small and Large Intestine (I): Malabsorption of Nutrients

Numerous disorders can alter the physiological mechanisms that guarantee proper digestion and absorption of nutrients (macro- and micronutrients), leading to a wide variety of symptoms and nutritional consequences. Malabsorption can be caused by many diseases of the small intestine, as well as by diseases of the pancreas, liver, biliary tract, and stomach. This article provides an overview of pathophysiologic mechanisms that lead to symptoms or complications of maldigestion (defined as the defective intraluminal hydrolysis of nutrients) or malabsorption (defined as defective mucosal absorption), as well as its clinical consequences, including both gastrointestinal symptoms and extraintestinal manifestations and/or laboratory abnormalities. The normal uptake of nutrients, vitamins, and minerals by the gastrointestinal tract (GI) requires several steps, each of which can be compromised in disease. This article will first describe the mechanisms that lead to poor assimilation of nutrients, and secondly discuss the symptoms and nutritional consequences of each specific disorder. The clinician must be aware that many malabsorptive disorders are manifested by subtle disorders, even without gastrointestinal symptoms (for example, anemia, osteoporosis, or infertility in celiac disease), so the index of suspicion must be high to recognize the underlying diseases in time.

Determination of modifiable risk factors for length-for-age z-scores among resource-poor Indonesian infants

To reduce the burden of early-life linear growth faltering in low- and middle-income countries, interventions have focused on nutrition strategies, sometimes combined with water quality, sanitation, and hygiene (WASH). However, even when combined, their effects on linear growth have been inconsistent. Here, we investigate potential predictors of length-for-age z-scores (LAZ) in a cohort of resource-poor rural Indonesian infants to inform the optimal strategies to reduce linear growth faltering. Apparently healthy rural breastfed Indonesian infants were randomly selected from birth registries at age 6 months (n = 230) and followed up at 9 (n = 202) and 12 (n = 190) months. Using maximum likelihood estimation, we examined longitudinal relationships among socio-demographic status, maternal height, infant sex, age, water source, sanitation facility, energy, protein, micronutrient intakes and biomarkers (serum ferritin, zinc, retinol binding protein (RBP), selenium-adjusted for inflammation), and α-1-acid glycoprotein (AGP) and C-reactive protein (CRP) (systemic inflammation biomarkers) at age 6 and 9 months on LAZ at age 9 and 12 months. Stunting (LAZ <-2) at 6, 9, and 12 months was 15.7%, 19.3%, and 22.6%, respectively. In the full model, the predictor variable at age 6 months that was most strongly associated with infant LAZ at 9 months was maternal height (0.18 (95% CI 0.03, 0.32) SD). At age 9 months, the strongest predictors of LAZ at 12 months were improved drinking water source (-0.40 (95% CI -0.65, -0.14) vs. not improved), elevated AGP compared to not elevated (0.26 (95%CI -0.06, 0.58), maternal height (0.16 (95% CI 0.02, 0.31) SD), sex (0.22 (95% CI -0.02,0.45) female vs. male), serum RBP (0.12 (95% CI -0.01, 0.25) SD), and protein intake (0.17 (95% CI -0.01, 0.35) SD). Health promotion that includes exclusive breastfeeding up to the first six months and follows microbial water quality guidelines to ensure water intake is always safe should be considered.

Serum Biomarkers of Environmental Enteric Dysfunction and Growth Perspective in Egyptian Children

BACKGROUND: Environmental enteric dysfunction (EED) is a chronic subclinical condition, contributed to limited sources and poor countries. EED pathology is concerned with small intestine structure and function, which affect the macronutrients and micronutrients absorption with consequent growth faltering. AIM: This study aimed to evaluate some serum biomarkers involved in EED and determine their association with stunting and faltering growth in children; zonulin, endotoxin core antibody (EndoCAb), high-sensitive C-reactive protein (hsCRP), alpha-1-acid glycoprotein (AGP), and tumor necrosis factor (TNF), serum iron, and Vitamins A and D. PATIENTS AND METHODS: This case–control study enrolled 105 children aged from 1 to 10 years old, having weight-for-age z-scores and height-for-age z-scores (WAZ or HAZ) ranging from −1.5 to −2. They were compared with control group consisted of 100 children having WAZ or HAZ > −1 of matched age and sex. Assessment of serum markers levels of enteric dysfunction (zonulin and EndoCAb), markers of systemic inflammation (Hs CRP and AGP), along with serum micronutrients (vitamin A, vitamin D and iron) in children with malnutrition in comparison to controls. RESULTS: There was a highly significant decrease as regarding the anthropometric measurements; weight, height, BMI, and arm circumference. Moreover, significant increase in serum zonulin, EndoCAb, HsCRP, and AGP and highly significant decrease of serum Vitamin D and iron in cases group as compared to control group. Height Z score showed negative correlation with zonulin, HsCRP, and AGP and positive correlation with Vitamin D. Weight Z score showed negative correlation with zonulin, HsCRP, and AGP and positive correlation with Vitamin D and Vitamin A. Regression analysis noted increase of zonulin and α1AGP as high associative markers with height Z score affection, however, increase of zonulin was high associative markers with weight Z score affection. CONCLUSION: Faltering growth is associated with elevated serum systemic markers of intestinal inflammation (HsCRP and α1AGP). EED may be a cause of faltering growth.

Frequency of Cryptosporidiosis in Children having Persistent Diarrhea

Objective:

Globally childhood diarrheal diseases continue to be the second leading cause of death. Cryptosporidium spp are important intestinal parasites that cause diarrhea in humans and animals particularly in developing countries. This investigation was carried out to find out the frequency of cryptosporidiosis in children presenting with persistent diarrhea.

Methods:

Two hundred stool samples were collected in this descriptive cross-sectional study conducted at Microbiology Department, Combined Military Hospital, Lahore Pakistan between the months of July to Dec 2014. Children aged five years to 12 years who presented with persistent diarrhea were included in the study. Stool specimens were processed using the modified acid-fast staining method, and microscopically examined for Cryptosporidium infection.

Results:

The average age of study participants was 7.95 with a standard deviation of 2.21 years. Among the participants 66% were males whereas 34% were females. Twenty eight percent had presence of oocysts in stool samples.

Conclusions:

The frequency of Cryptosporidiosis among children with persistent diarrhea was 28%. This high frequency indicates that this population is uniquely susceptible to infection. It also highlights the need for education about hygiene, accurate diagnosis, and treatment of Cryptosporidiosis. There is also a need for additional studies regarding the occurrence of this pathogen.

The effect of access to water, sanitation and handwashing facilities on child growth indicators: Evidence from the Ethiopia Demographic and Health Survey 2016

INTRODUCTION

Poor access to water, sanitation, and handwashing (WASH) facilities frequently contribute to child growth failure. The role of access to WASH facilities on child growth outcomes in Ethiopia is largely unknown. The aim of this study was to determine individual and combined effects of access to WASH facilities on child growth outcomes.

METHODS

Data for this analysis was sourced from the recent Ethiopia Demographic and Health Survey (EDHS) 2016. A multivariable logistic regression model was applied to identify the separate and combined association of access to WASH facilities with child growth outcomes. Odds ratio (OR) and 95% confidence interval (CI) were estimated. Statistical significance was declared at p < 0.05.

RESULTS

Included in the analyses were data for children 0-59 months of age, which amounted to valid data for 9588 children with a height-for-age z-score (HAZ), 9752 children with a weight-for-age z-score (WAZ) and 9607 children with a weight-for-height z-score (WHZ). Children with access to improved combined sanitation with handwashing facilities had 29% lower odds of linear growth failure (stunting) (adjusted odds ratio (AOR) = 0.71; 95% CI: 0.51-0.99) compared with those with unimproved. Children with access to combined improved WASH facilities were 33% less likely to have linear growth failure (AOR = 0.67; 95% CI: 0.45-0.98). Access to improved handwashing alone reduced the odds of being underweight by 17% (AOR = 0.83; 95% CI: 0.71-0.98) compared with unimproved. Improved water and sanitation separately as well as combined WASH were not associated with decreased odds of underweight and wasting.

CONCLUSIONS

Combined access to improved water, sanitation and handwashing was associated with reduced child linear growth failure. Further research with robust methods is needed to examine whether combined WASH practices have synergistic effect on child growth outcomes.

Livestock ownership and anaemia in Sub-Saharan African households

OBJECTIVE

To determine the association between livestock ownership and Hb concentration of women of child-bearing age (WCBA) and preschool-aged children in Sub-Saharan Africa (SSA).

DESIGN

A prospective analysis of publicly available cross-sectional data, using linear and logistic regressions controlling for potential confounders.

SETTING

Twenty-eight countries in SSA.

PARTICIPANTS

162 305 WCBA and 118 607 children aged 6-59 months.

RESULTS

More than half of WCBA (62·5 %) and children (58 %) belonged to households that owned livestock. The average altitude-adjusted blood Hb concentration for WCBA and children was 12.23 and 10·24 g/dL, respectively. In adjusted models, higher number of livestock owned was associated with lower Hb concentration for children but not for WCBA. The magnitude of the association for children was small, with one additional unit of livestock owned reducing Hb concentration by 0·001 g/dL. Higher numbers of cattle, cows and bulls, sheep, and goats were associated with lower Hb concentration for both groups. The number of certain categories of livestock owned was associated with the consumption of relevant foods by children. There was no association between the consumption of animal-source foods and Hb concentration or between livestock ownership and diarrhoeal diseases or fever among children.

CONCLUSIONS

Livestock ownership in SSA had a net negative association with the Hb concentration of children and no association with that of WCBA. The results highlight the need for research aimed at clarifying the mechanisms linking livestock ownership and nutritional status, and identifying entry points for leveraging livestock ownership to improve the health of women and children in SSA.

Markers of Environmental Enteric Dysfunction Are Associated with Poor Growth and Iron Status in Rural Ugandan Infants

BACKGROUND

Environmental enteric dysfunction (EED), characterized by altered intestinal permeability/inflammation, microbial translocation, and systemic inflammation (SI), may be a significant contributor to micronutrient deficiencies and poor growth in infants from low-resource settings.

OBJECTIVE

We examined associations among EED, SI, growth, and iron status at 6 mo of age.

METHODS

We performed a cross-sectional analysis of 6-mo-old infants (n = 548) enrolled in a Ugandan birth-cohort study (NCT04233944). EED was assessed via serum concentrations of anti-flagellin and anti- LPS immunoglobulins (Igs); SI was assessed via serum concentrations of ɑ1-acid glycoprotein (AGP) and C-reactive protein (CRP); iron status was assessed via serum concentrations of hemoglobin (Hb), soluble transferrin receptor (sTfR), and ferritin. Associations were assessed using adjusted linear regression analysis.

RESULTS

At 6 mo, ∼35% of infants were stunted [length-for-age z score (LAZ) < -2] and ∼53% were anemic [hemoglobin (Hb) <11.0 g/dL]. Nearly half (∼46%) had elevated AGP (>1 g/L) and ∼30% had elevated CRP (>5 mg/L). EED and SI biomarkers were significantly correlated (r = 0.142-0.193, P < 0.001 for all). In adjusted linear regression models, which included adjustments for SI, higher anti-flagellin IgA, anti-LPS IgA, and anti-LPS IgG concentrations were each significantly associated with lower LAZ [β (95% CI): -0.21 (-0.41, 0.00), -0.23 (-0.44, -0.03), and -0.33 (-0.58, -0.09)]. Furthermore, higher anti-flagellin IgA, anti-flagellin IgG, and anti-LPS IgA concentrations were significantly associated with lower Hb [β (95% CI): -0.24 (-0.45, -0.02), -0.58 (-1.13, 0.00), and -0.26 (-0.51, 0.00)] and higher anti-flagellin IgG and anti-LPS IgG concentrations were significantly associated with higher sTfR [β (95% CI): 2.31 (0.34, 4.28) and 3.13 (0.75, 5.51)].

CONCLUSIONS

EED is associated with both low LAZ and iron status in 6-mo-old infants. Further research on the mechanisms by which EED affects growth and micronutrient status is warranted.

Immunoglobulin recognition of fecal bacteria in stunted and non-stunted children: findings from the Afribiota study

BACKGROUND

Child undernutrition is a global health issue that is associated with poor sanitation and an altered intestinal microbiota. Immunoglobulin (Ig) A mediates host-microbial homeostasis in the intestine, and acutely undernourished children have been shown to have altered IgA recognition of the fecal microbiota. We sought to determine whether chronic undernutrition (stunting) or intestinal inflammation were associated with antibody recognition of the microbiota using two geographically distinct populations from the Afribiota project. Fecal bacteria from 200 children between 2 and 5 years old in Antananarivo, Madagascar, and Bangui, Central African Republic (CAR), were sorted into IgA-positive (IgA+) and IgA-negative (IgA-) populations by flow cytometry and subsequently characterized by 16S rRNA gene sequencing to determine IgA-bacterial targeting. We additionally measured IgG+ fecal bacteria by flow cytometry in a subset of 75 children.

RESULTS

Stunted children (height-for-age z-score ≤ -2) had a greater proportion of IgA+ bacteria in the fecal microbiota compared to non-stunted controls. This trend was consistent in both countries, despite the higher overall IgA-targeting of the microbiota in Madagascar, but lost significance in each country individually. Two of the most highly IgA-recognized bacteria regardless of nutritional status were Campylobacter (in CAR) and Haemophilus (in both countries), both of which were previously shown to be more abundant in stunted children; however, there was no association between IgA-targeting of these bacteria and either stunting or inflammatory markers. IgG-bound intestinal bacteria were rare in both stunted and non-stunted children, similar to levels observed in healthy populations.

CONCLUSIONS

Undernourished children carry a high load of intestinal pathogens and pathobionts. Our data suggest that stunted children have a greater proportion of IgA-recognized fecal bacteria. We moreover identify two putative pathobionts, Haemophilus and Campylobacter, that are broadly targeted by intestinal IgA. This study furthers our understanding of host-microbiota interactions in undernutrition and identifies immune-recognized microbes for future study.

Impact of Different Strategies for Delivering Supplemental Zinc on Selected Fecal Markers of Environmental Enteric Dysfunction among Young Laotian Children: A Randomized Controlled Trial

The objective of this study was to assess the impact of different strategies for delivering supplemental zinc on fecal myeloperoxidase (MPO), neopterin (NEO), and calprotectin (CAL) among young Laotian children. In a double-blind controlled trial, children aged 6-23 months were randomized to receive either daily preventive zinc (PZ) tablets (7 mg/day), daily micronutrient powder (MNP; containing 10 mg zinc and 14 other micronutrients), therapeutic zinc (TZ) supplements for diarrhea treatment (20 mg/day for 10 days), or daily placebo powder and followed for ∼36 weeks. Stool samples were collected at baseline and endline. Fecal MPO, NEO, and CAL concentrations were determined in a randomly selected subsample of 720 children using commercially available ELISA kits. At baseline, the mean age was 14.1 ± 4.9 months and prevalence of stunting was 39%. The endline prevalence of stunting was 43%; there was no overall treatment effect on physical growth in the parent trial. At endline, the mean (95% CI) MPO in the PZ group was 1,590 [1,396; 1,811] ng/mL and did not differ from that in the MNP (1,633 [1,434; 1,859] ng/mL), TZ (1,749 [1,535; 1,992] ng/mL), and control (1,612 [1,415; 1,836] ng/mL) groups (P = 0.749). Similarly, there was no overall treatment effect on NEO and CAL concentrations (P = 0.226 and 0.229, respectively). In this population, the provision of PZ or TZ supplements or MNP had no impact on growth or environmental enteric dysfunction (EED) as assessed by fecal MPO, NEO, and CAL. Additional research is needed to better understand the etiology and proposed mechanisms of EED pathogenesis.

HMIC: Hierarchical Medical Image Classification, A Deep Learning Approach

Image classification is central to the big data revolution in medicine. Improved information processing methods for diagnosis and classification of digital medical images have shown to be successful via deep learning approaches. As this field is explored, there are limitations to the performance of traditional supervised classifiers. This paper outlines an approach that is different from the current medical image classification tasks that view the issue as multi-class classification. We performed a hierarchical classification using our Hierarchical Medical Image classification (HMIC) approach. HMIC uses stacks of deep learning models to give particular comprehension at each level of the clinical picture hierarchy. For testing our performance, we use biopsy of the small bowel images that contain three categories in the parent level (Celiac Disease, Environmental Enteropathy, and histologically normal controls). For the child level, Celiac Disease Severity is classified into 4 classes (I, IIIa, IIIb, and IIIC).

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

Background

Because Helicobacter pylori (H. pylori) infection and Environmental Enteric Dysfunction (EED) follow a similar mode of transmission, there can be a complex interplay between H. pylori infection and EED, both of which can influence childhood growth. We sought to investigate the factors associated with H. pylori infection and identify its relationship with the fecal biomarkers of EED including Myeloperoxidase (MPO), Neopterin (NEO), Calprotectin, Reg1B and Alpha-1 antitrypsin (AAT), and nutritional status of the children.

Methodology

Data from an on-going community-based nutrition intervention study was used for this analysis. Total 319 children aged between 12–18 months were evaluated at enrolment and at the end of a 90-day nutrition intervention. Multivariable linear regression with generalized estimating equations was done to examine the association of H. pylori infection with stool biomarker of EED and nutritional status of the children.

Principal findings

One-fifth of the participants had H. pylori infection at both the time points, with 13.8% overall persistence. Children living in crowded households had higher odds of being infected by H. pylori (AOR = 2.02; 95% CI = 1.02, 4.10; p-value = 0.045). At enrolment, 60%, 99%, 69% and 85% of the stool samples were elevated compared to the reference values set for MPO, NEO, AAT and Calprotectin in the non-tropical western countries. The proportions reduced to 52%, 99%, 67%, and 77% for the same biomarkers after the nutrition intervention. Infection with H. pylori had significant positive association with fecal AAT concentrations (Coefficient = 0.26; 95% CI = 0.02, 0.49; p-value = 0.03) and inverse relationship with Reg1B concentrations measured in the stool samples (Coefficient = -0.32; 95% CI = -0.59, -0.05; p-value = 0.02). However, H. pylori infection was not associated with the indicators of childhood growth.

Conclusions

The study findings affirmed that the acquisition and persistence of H. pylori infection in the early years of life may exert an adverse impact on intestinal health, induce gut inflammation and result in increased intestinal permeability.

Infection with H. pylori, a substantial public health burden in the tropical countries, follows the similar mode of transmission analogous to Environmental Enteric Dysfunction (EED). There can be a complex interplay between H. pylori infection and EED–both of which can influence childhood growth–but the definite role of H. pylori infection contributing to EED and subsequent growth failure is poorly understood. In this study, the authors present data from an ongoing community-based nutrition intervention study and investigated the factors associated with H. pylori infection and identify its relationship with fecal biomarkers of EED and indicators of the nutritional status of the children hailing from a resource-poor urban settlement. They demonstrated the acquisition and persistence of H. pylori infection during early childhood. The study results also corroborate that infection with H. pylori had significant positive association with fecal Alpha-1 antitrypsin concentrations and an inverse relationship with Reg1B concentrations measured in stool samples of the children. The findings revealed in this study may contribute to a better understanding of the role of H. pylori infection in contributing to EED as well as alteration of gut function in the early years of life.

Growth in Infants and Children With Intestinal Failure-associated Liver Disease Treated With Intravenous Fish Oil

BACKGROUND

Infants with intestinal failure (IF) and IF-associated liver disease (IFALD) are at risk for poor somatic growth because of increased metabolic demands, inadequate intake, intestinal malabsorption, chronic liver disease and other comorbidities. There are limited data on the nutritional adequacy of intravenous fish oil lipid emulsion (FOLE) compared with standard soybean oil lipid emulsion (SOLE) in the setting of intestinal failure.

AIMS

To describe growth patterns in a large cohort of infants with IFALD treated with FOLE.

METHODS

We compared growth data from infants enrolled in a single-center, prospective FOLE study to published norms, as well as to a multicenter, historical cohort of infants with IF treated with SOLE.

RESULTS

One hundred thirty-eight infants with IFALD were treated with FOLE and 108 with SOLE. Compared with normative growth curves from WHO and published preterm data, infants in both groups from 6 to 11 months postmenstrual age exhibited declines in mean weight- and length-for-age z scores. At 24 months postmenstrual age compared with WHO growth data, infants treated with FOLE had a mean (95% confidence interval [CI]) weight-for-age z-score of 0.13 (-0.18 to 0.45) and length-for-age z-score of 0.07 (-0.33 to 0.47). In comparison, at 24 months postmenstrual age, infants treated with SOLE had a mean weight for age z-score of -0.93 (-1.20 to -0.67) and mean length for age z-score of -2.33 (-2.75 to -1.91). Independent predictors of higher weight, length and head circumference z-scores included older postmenstrual age at baseline, fewer central line-associated blood stream infections, resolution of cholestasis, type of intravenous fat emulsion (FOLE vs SOLE) and female sex.

CONCLUSIONS

Infants with IFALD treated with FOLE showed comparable somatic growth to those treated with SOLE in early infancy, and improved somatic growth up to 24 months of age, supporting its wider use in this patient population.

Impact of Daily Preventive Zinc or Therapeutic Zinc Supplementation for Diarrhea on Plasma Biomarkers of Environmental Enteric Dysfunction among Rural Laotian Children: A Randomized Controlled Trial

Environmental enteric dysfunction (EED) may be ameliorated by zinc supplementation. The objective of this study was to investigate the impact of different forms of zinc supplementation on biomarkers of EED (i.e., plasma citrulline, kynurenine, and tryptophan concentrations and the kynurenine:tryptophan [KT] ratio) among young Laotian children. In a double-blind randomized controlled trial, 3,407 children aged 6-23 months were randomized into one of four groups: daily preventive zinc dispersible tablets (PZ; 7 mg zinc), daily multiple micronutrient powders (MNP; 10 mg zinc, 6 mg iron, and 13 other micronutrients), therapeutic zinc supplements for diarrhea treatment (TZ; 20 mg/day for 10 days), or daily placebo powder, and followed up for ∼36 weeks. Plasma samples at baseline and endline for 359 children were analyzed for citrulline, kynurenine, and tryptophan concentrations. At baseline, the prevalence of stunting and zinc deficiency was 37% and 76.5%, respectively. The mean plasma citrulline, kynurenine, and tryptophan concentrations were 24.6 ± 5.4 µmol/L, 3.27 ± 0.83 µmol/L, and 72.3 ± 12.9 µmol/L, respectively; the mean KT ratio (×1,000) was 45.9 ± 12.0. At endline, neither plasma citrulline, kynurenine, or tryptophan concentrations, nor the KT ratio differed among intervention groups (P > 0.05). In this population, PZ, MNP, and TZ had no overall effect on plasma concentrations of citrulline, kynurenine, and tryptophan, or the KT ratio. The need remains to better understand the etiology of EED, and the development of biomarkers to diagnose EED and evaluate the impact of interventions.

Water, sanitation and hygiene (WASH) in sub-Saharan Africa and associations with undernutrition, and governance in children under five years of age: a systematic review

Associations between different forms of malnutrition and environmental conditions, including water, sanitation and hygiene (WASH), may contribute towards persistently poor child health, growth and cognitive development. Experiencing poor nutrition in utero or during early childhood is furthermore associated with chronic diseases later in life. The primary responsibility for provision of water and sanitation, as a basic service and human right, lies with the State; however, a number of stakeholders are involved. The situation is most critical in sub-Saharan Africa (SSA), where, in 2015, 311 million people lacked a safe water source, and >70% of SSA populations were living without adequate sanitation. The aim of this paper was to conduct a systematic review to investigate the state of literature concerned with WASH and its association with nutritional status, and governance in children from birth to 5 years of age in SSA. Articles were sourced from PubMed Central, Science Direct and ProQuest Social Science databases published between 1990 and 2017. The PRISMA Statement was utilised and this systematic review is registered with PROSPERO (CRD42017071700). The search terms returned 15,351 articles for screening, with 46 articles included. This is indicative of a limited body of knowledge; however, the number of publications on this topic has been increasing, suggesting burgeoning field of interest. Targeted research on the governance of WASH through the identification of the various role players and stakeholders at various levels, while understanding the policy environment in relation to particular health-related outcomes is imperative to address the burden of child undernutrition.

Diagnosis of Celiac Disease and Environmental Enteropathy on Biopsy Images Using Color Balancing on Convolutional Neural Networks

Celiac Disease (CD) and Environmental Enteropathy (EE) are common causes of malnutrition and adversely impact normal childhood development. CD is an autoimmune disorder that is prevalent worldwide and is caused by an increased sensitivity to gluten. Gluten exposure destructs the small intestinal epithelial barrier, resulting in nutrient mal-absorption and childhood under-nutrition. EE also results in barrier dysfunction but is thought to be caused by an increased vulnerability to infections. EE has been implicated as the predominant cause of under-nutrition, oral vaccine failure, and impaired cognitive development in low-and-middle-income countries. Both conditions require a tissue biopsy for diagnosis, and a major challenge of interpreting clinical biopsy images to differentiate between these gastrointestinal diseases is striking histopathologic overlap between them. In the current study, we propose a convolutional neural network (CNN) to classify duodenal biopsy images from subjects with CD, EE, and healthy controls. We evaluated the performance of our proposed model using a large cohort containing 1000 biopsy images. Our evaluations show that the proposed model achieves an area under ROC of 0.99, 1.00, and 0.97 for CD, EE, and healthy controls, respectively. These results demonstrate the discriminative power of the proposed model in duodenal biopsies classification.

Artificial Intelligence Applied to Gastrointestinal Diagnostics: A Review

Artificial intelligence (AI), a discipline encompassed by data science, has seen recent rapid growth in its application to healthcare and beyond, and is now an integral part of daily life. Uses of AI in gastroenterology include the automated detection of disease and differentiation of pathology subtypes and disease severity. Although a majority of AI research in gastroenterology focuses on adult applications, there are a number of pediatric pathologies that could benefit from more research. As new and improved diagnostic tools become available and more information is retrieved from them, AI could provide physicians a method to distill enormous amounts of data into enhanced decision-making and cost saving for children with digestive disorders. This review provides a broad overview of AI and examples of its possible applications in pediatric gastroenterology.

Environmental enteric dysfunction: a review of potential mechanisms, consequences and management strategies

BACKGROUND

Environmental enteric dysfunction (EED) is an acquired enteropathy of the small intestine, characterized by enteric inflammation, villus blunting and decreased crypt-to-villus ratio. EED has been associated with poor outcomes, including chronic malnutrition (stunting), wasting and reduced vaccine efficacy among children living in low-resource settings. As a result, EED may be a valuable interventional target for programs aiming to reduce childhood morbidity in low and middle-income countries.

MAIN TEXT

Several highly plausible mechanisms link the proposed pathophysiology underlying EED to adverse outcomes, but causal attribution of these pathways has proved challenging. We provide an overview of recent studies evaluating the causes and consequences of EED. These include studies of the role of subclinical enteric infection as a primary cause of EED, and efforts to understand how EED-associated systemic inflammation and malabsorption may result in long-term morbidity. Finally, we outline recently completed and upcoming clinical trials that test novel interventions to prevent or treat this highly prevalent condition.

CONCLUSIONS

Significant strides have been made in linking environmental exposure to enteric pathogens and toxins with EED, and in understanding the multifactorial mechanisms underlying this complex condition. Further insights may come from several ongoing and upcoming interventional studies trialing a variety of novel management strategies.