Evaluating the Alimentary and Respiratory Tracts in Health and disease (EARTH) research programme: a protocol for prospective, longitudinal, controlled, observational studies in children with chronic disease at an Australian tertiary paediatric hospital

Intestinal dysbiosis and inflammation in children with repaired esophageal atresia

OBJECTIVES

This study aims to compare the intestinal microbiota and intestinal inflammation of children with esophageal atresia (EA) to matched healthy controls, and to investigate the relationship between these factors and clinical outcomes.

METHODS

A cross-sectional study of 35 children with EA and 35 matched healthy controls (HC) from a single tertiary pediatric hospital in Australia was conducted. Demographic and dietary data were collected using surveys. Stool samples were analyzed using 16S rRNA sequencing, and fecal calprotectin measurements were used to measure intestinal inflammation. Comparisons were made between the groups, and correlations between the microbiota and clinical factors were investigated in the EA cohort.

RESULTS

Compared to HC, children with EA had similar alpha diversity, but beta diversity analysis revealed clustering of EA and HC cohorts. Children with EA had a significantly higher relative abundance of the order Lactobacillales, and a lower abundance of the genus uncultured Bacteroidales S24-7. Fecal calprotectin was significantly higher in children with EA compared to HC. In the EA cohort, children taking proton pump inhibitors (PPI's) had lower alpha diversity and higher calprotectin levels compared to those not taking PPI's. There was a negative correlation between calprotectin and length/height-for-age z scores, and children with higher calprotectin levels had a greater burden of gastrointestinal symptoms.

CONCLUSIONS

Children with EA have an altered intestinal microbiota compared to HC, which is likely related to PPI use, and may be impacting on growth and quality of life. It is important to rationalize PPI use in this cohort.

The correlation of the intestinal with pharyngeal microbiota in early neonates

Introduction

The gut-lung axis has long been recognized as an important mechanism affecting intestinal and lung immunity. Still, few studies have examined the correlation between the intestinal and pharyngeal microbiota in early neonates, especially when feeding patterns are one of the main drivers of microbiota development.

Methods

To explore the composition and function of intestinal and pharyngeal microbiota and to analyze the effect of limited formula feeding on the initial microbiota colonization in early full-term neonates, we characterized the stool and oropharyngeal microbiota of 20 healthy full-term newborns sampled on days 0 and 5-7 after birth using 16S rRNA gene sequencing. Based on the sequencing results, a comparison was made of the compositions and functions of the intestinal and oropharyngeal microbiota for analysis.

Results and discussion

At the phylum level, Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes were the most abundant in both niches. At the genus level, the species of pioneer bacteria were rich in the intestine and oropharynx but low in abundance on day 0. On days 5-7, Bifidobacterium (25.40%) and Escherichia-Shigella (22.16%) were dominant in the intestine, while Streptococcus (38.40%) and Staphylococcus (23.13%) were dominant in the oropharynx. There were eight core bacteria genera in the intestine and oropharynx on days 5-7, which were Bifidobacterium, Escherichia-Shigella, Staphylococcus, Streptococcus, Bacteroides, Parabacteroides, Rothia, and Acinetobacter. As indicated by PICRUSt analysis, on days 5-7, the intestinal microbiota was more predictive than the oropharyngeal microbiota in transcription, metabolism, cell motility, cellular processes and signaling, and organismal system function in the KEGG pathway. Compared to exclusive breastfeeding, limited formula feeding (40-60%) had no significant effect on the neonatal intestinal and oropharyngeal microbiota composition during the initial colonization period. Our results suggest that the initial colonization of microbiota is closely related to the ecological niche environment in the intestine and oropharynx, with their core microbiota being closely correlated. We found that early limited formula feeding could not significantly affect the initial colonization of microbiota in the intestine and oropharynx.

Diet and the gut-lung axis in cystic fibrosis - direct & indirect links

Cystic fibrosis (CF) is a multisystem, autosomal, recessive disease primarily affecting the lungs, pancreas, gastrointestinal tract, and liver. Whilst there is increasing evidence of a microbial 'gut-lung axis' in chronic respiratory conditions, there has been limited analysis of such a concept in CF. We performed a comprehensive dietary and microbiota analysis to explore the interactions between diet, gastrointestinal microbiota, respiratory microbiota, and clinical outcomes in children with CF. Our results demonstrate significant alterations in intestinal inflammation and respiratory and gastrointestinal microbiota when compared to age and gender matched children without CF. We identified correlations between the gastrointestinal and respiratory microbiota, lung function, CF pulmonary exacerbations and anthropometrics, supporting the concept of an altered gut-lung axis in children with CF. We also identified significant differences in dietary quality with CF children consuming greater relative proportions of total, saturated and trans fats, and less relative proportions of carbohydrates, wholegrains, fiber, insoluble fiber, starch, and resistant starch. Our findings position the CF diet as a potential modulator in gastrointestinal inflammation and the proposed gut-lung axial relationship in CF. The dietary intake of wholegrains, fiber and resistant starch may be protective against intestinal inflammation and should be explored as potential therapeutic adjuvants for children with CF.

Evaluating the Dietary Intake of Children With Esophageal Atresia: A Prospective, Controlled, Observational Study

OBJECTIVES

Children with esophageal atresia (EA) often have feeding difficulties and dysphagia, which may compromise their nutritional status. This study aimed to compare dietary intake between children with EA and matched healthy controls (HC) and to investigate the relationship between dietary factors, growth, dysphagia, and feeding difficulties in the EA cohort.

METHODS

This cross-sectional cohort study recruited children with EA and HC aged 2-17 years from a tertiary pediatric hospital in Australia. Growth parameters were measured. Dietary intake was assessed using the validated Australian Child and Adolescent Eating Survey. Dysphagia and feeding difficulties were assessed using objective questionnaires.

RESULTS

Twenty-one children with EA were matched for age and sex with 21 HC. Compared to HC, children with EA had lower mean z scores for height-for-age, but mean weight-for-age and body mass index-for-age z scores were similar. Energy intake was similar between the groups. The diet of children with EA consisted of a higher proportion of fats and lower proportion of carbohydrates compared to matched HC. Dysphagia severity in children with EA positively correlated with proportion of energy from fats and saturated fats.

CONCLUSIONS

Children with EA have similar energy intake and growth parameters to HC, but their diet consists of a higher proportion of fats and lower proportion of carbohydrates compared to HC. Targeted dietary interventions and parental education are necessary.