Chronic enteropathy and feeding in children: an update

A prebiotic-enhanced lipid-based nutrient supplement (LNSp) increases Bifidobacterium relative abundance and enhances short-chain fatty acid production in simulated colonic microbiota from undernourished infants

Undernutrition remains a public health problem in the developing world with an attributable under-five death proportion of 45%. Lower gut microbiota diversity and poor metabolic output are associated with undernutrition and new therapeutic paths may come from steering gut microbiota composition and functionality. Using a dynamic gut model, the Simulator of Human Intestinal Microbial Ecosystem (SHIME®), we investigated the effect of a lipid-based nutrient supplement enriched with prebiotics (LNSp), compared to LNS alone and control treatment, on the composition and metabolic functionality of fecal microbiota from three infants suffering from undernutrition. LNS elicited a significant increase in acetate and branched-chain fatty acid production, and a higher relative abundance of the genera Prevotella, Megasphaera, Acinetobacter, Acidaminococcus and Pseudomonas. In contrast, LNSp treatment resulted in a significant 9-fold increase in Bifidobacterium relative abundance and a decrease in that of potential pathogens and detrimental bacteria such as Enterobacteriaceae spp. and Bilophila sp. Moreover, the LNSp treatment resulted in a significantly higher production of acetate, butyrate and propionate, as compared to control and LNS. Our results suggest that provision of prebiotic-enhanced LNS to undernourished children could be a possible strategy to steer the microbiota toward a more beneficial composition and metabolic activity. Further in vivo investigations are needed to assess these effects and their repercussion on nutritional status.

Diagnosis and management of Non-IgE gastrointestinal allergies in breastfed infants-An EAACI Position Paper

It is well-established that food proteins, such as egg, soya, cow's milk and wheat, are detectable in breastmilk for many hours or days after ingestion. Exposure to these proteins is important to the process of developing tolerance but can also sometimes elicit IgE-mediated and non-IgE-mediated allergic symptoms in breastfed infants. Non-IgE-mediated allergy, outside of food protein-induced allergic proctocolitis and eosinophilic oesophagitis, is not well understood, leading to variations in the diagnosis and management thereof. A primary objective of the European Academy for Allergy and Clinical Immunology is to support breastfeeding in all infants, including those with food allergies. A Task Force was established, to explore the clinical spectrum of non-IgE-mediated allergies, and part of its objectives was to establish diagnosis and management of non-IgE-mediated allergies in breastfed infants. Eight questions were formulated using the Patient, Intervention, Comparison, Outcome (PICO) system and Scottish Intercollegiate Guideline Network (SIGN) criteria for data inclusion, and consensus was achieved on practice points through the Delphi method. This publication aims to provide a comprehensive overview on this topic with practice points for healthcare professionals.

Mortality in children with complicated severe acute malnutrition is related to intestinal and systemic inflammation: an observational cohort study

BACKGROUND

Diarrhea affects a large proportion of children with severe acute malnutrition (SAM). However, its etiology and clinical consequences remain unclear.

OBJECTIVE

We investigated diarrhea, enteropathogens, and systemic and intestinal inflammation for their interrelation and their associations with mortality in children with SAM.

DESIGN

Intestinal pathogens (n = 15), cytokines (n = 29), fecal calprotectin, and the short-chain fatty acids (SCFAs) butyrate and propionate were determined in children aged 6-59 mo (n = 79) hospitalized in Malawi for complicated SAM. The relation between variables, diarrhea, and death was assessed with partial least squares (PLS) path modeling.

RESULTS

Fatal subjects (n = 14; 18%) were younger (mean ± SD age: 17 ± 11 compared with 25 ± 11 mo; P = 0.01) with higher prevalence of diarrhea (46% compared with 18%, P = 0.03). Intestinal pathogens Shigella (36%), Giardia (33%), and Campylobacter (30%) predominated, but their presence was not associated with death or diarrhea. Calprotectin was significantly higher in children who died [median (IQR): 1360 mg/kg feces (2443-535 mg/kg feces) compared with 698 mg/kg feces (1438-244 mg/kg feces), P = 0.03]. Butyrate [median (IQR): 31 ng/mL (112-22 ng/mL) compared with 2036 ng/mL (5800-149 ng/mL), P = 0.02] and propionate [median (IQR): 167 ng/mL (831-131 ng/mL) compared with 3174 ng/mL (5819-357 ng/mL), P = 0.04] were lower in those who died. Mortality was directly related to high systemic inflammation (path coefficient = 0.49), whereas diarrhea, high calprotectin, and low SCFA production related to death indirectly via their more direct association with systemic inflammation.

CONCLUSIONS

Diarrhea, high intestinal inflammation, low concentrations of fecal SCFAs, and high systemic inflammation are significantly related to mortality in SAM. However, these relations were not mediated by the presence of intestinal pathogens. These findings offer an important understanding of inflammatory changes in SAM, which may lead to improved therapies. This trial was registered at www.controlled-trials.com as ISRCTN13916953.

The MAL-ED study: a multinational and multidisciplinary approach to understand the relationship between enteric pathogens, malnutrition, gut physiology, physical growth, cognitive development, and immune responses in infants and children up to 2 years of age in resource-poor environments

Highly prevalent conditions with multiple and complex underlying etiologies are a challenge to public health. Undernutrition, for example, affects 20% of children in the developing world. The cause and consequence of poor nutrition are multifaceted. Undernutrition has been associated with half of all deaths worldwide in children aged <5 years; in addition, its pernicious long-term effects in early childhood have been associated with cognitive and physical growth deficits across multiple generations and have been thought to suppress immunity to further infections and to reduce the efficacy of childhood vaccines. The Etiology, Risk Factors, and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health (MAL-ED) Study, led by the Fogarty International Center of the National Institutes of Health and the Foundation for the National Institutes of Health, has been established at sites in 8 countries with historically high incidence of diarrheal disease and undernutrition. Central to the study is the hypothesis that enteropathogen infection contributes to undernutrition by causing intestinal inflammation and/or by altering intestinal barrier and absorptive function. It is further postulated that this leads to growth faltering and deficits in cognitive development. The effects of repeated enteric infection and undernutrition on the immune response to childhood vaccines is also being examined in the study. MAL-ED uses a prospective longitudinal design that offers a unique opportunity to directly address a complex system of exposures and health outcomes in the community-rather than the relatively rarer circumstances that lead to hospitalization-during the critical period of development of the first 2 years of life. Among the factors being evaluated are enteric infections (with or without diarrhea) and other illness indicators, micronutrient levels, diet, socioeconomic status, gut function, and the environment. MAL-ED aims to describe these factors, their interrelationships, and their overall impact on health outcomes in unprecedented detail, and to make individual, site-specific, and generalized recommendations regarding the nature and timing of possible interventions aimed at improving child health and development in these resource-poor settings.

Predictors of poor CD4 and weight recovery in HIV-infected children initiating ART in South Africa

OBJECTIVE

To identify baseline demographic and clinical risk factors associated with poor CD4 and weight response after initiation of antiretroviral therapy (ART) in a cohort of human immunodeficiency virus (HIV)-infected children in KwaZulu-Natal, South Africa.

METHODS

We performed a retrospective cohort study of 674 children initiating antiretroviral therapy at McCord and St. Mary's hospitals in KwaZulu-Natal, South Africa, from August 2003 to December 2008. We extracted data from paper charts and electronic medical records to assess risk factors associated with CD4 and weight response using logistic regression.

RESULTS

From the initial cohort of 901 children <10 years old initiating ART between August 2003 and December 2008, we analyzed 674 children with complete baseline data. Viral suppression rates (<400 copies/ml) were 84% after six months of therapy and 88% after 12 months of therapy. Seventy-three percent of children achieved CD4 recovery after six months and 89% after 12 months. Weight-for-age Z-score (WAZ) improvements were seen in 58% of children after six months of ART and 64% after 12 months. After six months of ART, lower baseline hemoglobin (p = 0.037), presence of chronic diarrhea (p = 0.007), and virologic failure (p = 0.046) were all associated with poor CD4 recovery by multivariate logistic regression. After 12 months of ART, poor CD4 recovery was associated with higher baseline CD4% (p = 0.005), chronic diarrhea (p = 0.02), and virologic failure (p<0.001). Age less than 3 years at ART initiation (p = 0.0003), higher baseline CD4% (p<0.001), and higher baseline WAZ (p<0.001) were all associated with poor WAZ improvements after 6 months by multivariate logistic regression.

CONCLUSION

The presence of chronic diarrhea at baseline, independent of nutritional status and viral response, predicts poor CD4 recovery. Age at initiation of ART is an important factor in early WAZ response to ART, while viral suppression strongly predicts CD4 recovery but not WAZ improvement.

Effect of enteral nutrition on dextran sulfate sodium-induced colitis in rats

OBJECTIVE

To study the effect of enteral nutrition (EN) on dextran sulfate sodium (DSS)-induced colitis in rats.

METHODS

Eighty-four Sprague-Dawley rats were divided into 7 groups (12 rats in each group). The blank control group was given ordinary laboratory feed and drinking water. The experimental groups received 5% DSS as drinking water for 7 days. Of the experimental groups, the model control group received ordinary laboratory feed, protein based enteral nutrition (PEN) was fed in the PEN group, while other groups received ordinary laboratory feed plus 5-aminosalicylic acid (5-ASA), methyl-prednisolone, Lactobacillus or glutamine, respectively. On the 8th day, all the rats were sacrificed. Inflammatory scores were assessed from colonic mucosa. Blood culture from inferior vena cava, fecal culture and secretary immunoglobulin-A (S-IgA) levels from colonic contents were determined.

RESULTS

Colon inflammatory scores of Lactobacillus, PEN, glutamine and drug-treated groups were lower than that of the model control group (P < 0.01). The ratios of bacteria translocation in the EN (PEN, Lactobacillus and glutamine) groups were lower than that in the model control group (P < 0.0083). Fecal Lactobacilli in the Lactobacillus and glutamine groups were higher than that in the model control group (P < 0.05). S-IgA levels in colonic contents of the PEN and 5-ASA group were lower than that in the model control group (P < 0.05).

CONCLUSIONS

EN is an effective therapy for treating DDS-induced colitis. EN could alleviate damage, promote the repair of colonic epithelial cells and inhibit bacterial translocation. Lactobacillus and glutamine could also increase the Lactobacilli in colon.

Oral tolerance induction does not resolve gastrointestinal inflammation in a mouse model of food allergy

SCOPE

Oral immunotherapy (OIT) involving continuous oral administration of allergenic foods has gained attention as a therapy for food allergies. To study the influence of oral administration of allergenic foods on gastrointestinal symptoms including inflammation, we established a mouse model of food-induced intestinal allergy.

METHODS AND RESULTS

BALB/c mice were fed an egg white (EW) diet containing ovalbumin (OVA, a major EW allergen) after intraperitoneal sensitisation with OVA and Alum. The mice on the EW diet for one wk presented gastrointestinal symptoms (i.e. weight loss and soft stools) and inflammation in the small intestines (i.e. duodenum, jejunum and ileum). Further continuous EW diet resolved the weight loss but not the soft stools. Splenic CD4(+) T-cells of EW diet-fed mice on the continuous diet showed less proliferation and cytokine production compared with those of control mice, suggesting tolerance induction by the diet. The continuous EW diet reduced levels of OVA-specific IgE antibodies, but significantly aggravated the inflammation in the jejunum.

CONCLUSION

Our mouse model would be useful to investigate inflammatory and regulatory mechanisms in food-induced intestinal allergies. Our results suggest potential gastrointestinal inflammation in patients undergoing OIT as continuous administration of allergenic foods, even though the therapy may induce clinical tolerance.

The anti-deamidated gliadin peptide antibodies unmask celiac disease in small children with chronic diarrhoea

OBJECTIVES

To assess the usefulness of a new class of antibodies, the anti-deamidated gliadin peptides, in the diagnostic approach to children less than 2 years with suspected celiac disease.

PATIENTS AND METHODS

We investigated 40 children (median age: 16.8 months; age range: 4-24 months), with symptoms and signs of chronic enteropathy and high serum levels of conventional anti-gliadin antibodies, but normal values of anti-transglutaminase and anti-endomysial antibodies; all underwent measurement of anti-deamidated gliadin peptides serum levels, upper gastrointestinal endoscopy with biopsies and HLA typing; 40 subjects served as controls.

RESULTS

In 29 patients (group A) serum levels of anti-deamidated gliadin peptides were normal and duodenal histology showed a spectrum of abnormalities ranging from mucosal inflammatory infiltrates to villous damage (in almost all cases compatible with Marsh 1-to-2 lesions). All improved on a cow's and soy milk free diet containing gluten. In 11 patients (group B) there were high serum levels of anti-deamidated gliadin peptides and histology showed features suggestive of celiac disease (Marsh 2-to-3 lesions) in all; furthermore, human leucocyte antigen typing was consistent with a celiac disease genetic pattern in all. Group B patients significantly improved on a gluten free diet containing cow's and soy milk proteins. None of the control group was anti-deamidated gliadin peptides positive.

CONCLUSIONS

In children younger than 2 years with signs of chronic enteropathy and normal values of classical serum markers of celiac disease, the latter can be predicted by high serum levels of anti-deamidated gliadin peptides.

Mass Spectrometry for the Analysis of Milk Oligosaccharides

Mass Spectrometry (MS) has emerged as an indispensable tool for the analysis of biomolecules due to its sensitivity, versatility and ease of applicability to complex samples. Nevertheless, the analysis of free oligosaccharides and protein bound sugars in secretions such as milk poses certain challenges. In this review, the benefits and limitations of different sample preparation approaches for the mass spectrometric analysis of free oligosaccharides and glycoproteins are discussed. Appropriate sample preparation is the first crucial step for successful mass spectrometric analysis. Different MS techniques and instrument combinations already successfully applied to the analysis of milk oligosaccharides are also introduced. Available tandem and MSn applications for the differentiation of structural isomers are described and their limitations discussed. This review is intended to give an overview on the available MS methodology and technology available for analysing various kinds of oligosaccharides in milk.