Human milk cream alters intestinal microbiome of preterm infants: a prospective cohort study.

BACKGROUND: In very low birth weight (VLBW) infants, human milk cream added to standard human milk fortification is used to improve growth. This study aimed to evaluate the impact of cream supplement on the intestinal microbiome of VLBW infants. METHODS: Whole genome shotgun sequencing was performed on stool (n = 57) collected from a cohort of 23 infants weighing 500-1250 grams (control = 12, cream = 11). Both groups received an exclusive human milk diet (mother's own milk, donor human milk, and donor human milk-derived fortifier) with the cream group receiving an additional 2 kcal/oz cream at 100 mL/kg/day of fortified feeds and then 4 kcal/oz if poor growth. RESULTS: While there were no significant differences in alpha diversity, infants receiving cream significantly differed from infants in the control group in beta diversity. Cream group samples had significantly higher prevalence of Proteobacteria and significantly lower Firmicutes compared to control group. Klebsiella species dominated the microbiota of cream-exposed infants, along with bacterial pathways involved in lipid metabolism and metabolism of cofactors and amino acids. CONCLUSIONS: Cream supplementation significantly altered composition of the intestinal microbiome of VLBW infants to favor increased prevalence of Proteobacteria and functional gene content associated with these bacteria. IMPACT: We report changes to the intestinal microbiome associated with administration of human milk cream; a novel supplement used to improve growth rates of preterm very low birth weight infants. Since little is known about the impact of cream on intestinal microbiota composition of very low birth weight infants, our study provides valuable insight on the effects of diet on the microbiome of this population. Dietary supplements administered to preterm infants in neonatal intensive care units have the potential to influence the intestinal microbiome composition which may affect overall health status of the infant.

Fatty acid concentrations in preterm infants fed the exclusive human milk diet: a prospective cohort study.

OBJECTIVE: Quantify blood fatty acids and growth outcomes in preterm infants fed the exclusive human milk diet. METHODS: A prospective cohort study of 30 infants 24-34 weeks gestation and ≤1250 g fed the exclusive human milk diet. Blood fatty acids were quantified at two time points. Comparisons were made using two-sample t-tests and Wilcoxon rank sum. RESULTS: Donor human milk-fed (n = 12) compared to mother's own milk-fed infants (n = 18) from birth to after 28 days of life, had an increased interval change of linoleic to docosahexaenoic acid ratio (5.5 vs. -1.1 mole percent ratio, p = 0.034). Docosahexaenoic and eicosapentaenoic acid interval changes were similar between groups. The arachidonic acid change was similar between groups (-2.3 vs. -0.9 mole percent, p = 0.37), however, both experienced a negative change across time. At 36 weeks postmenstrual age, growth velocities were similar for groups. CONCLUSION: An exclusive human milk diet maintains birth docosahexaenoic and eicosapentaenoic acid concentrations. However, the postnatal deficit in arachidonic acid was not prevented.

Cholestasis impairs gut microbiota development and bile salt hydrolase activity in preterm neonates.

Cholestasis refers to impaired bile flow from the liver to the intestine. In neonates, cholestasis causes poor growth and may progress to liver failure and death. Normal bile flow requires an intact liver-gut-microbiome axis, whereby liver-derived primary bile acids are transformed into secondary bile acids. Microbial bile salt hydrolase (BSH) enzymes are responsible for the first step, deconjugating glycine- and taurine-conjugated primary bile acids. Cholestatic neonates often are treated with the potent choleretic bile acid ursodeoxycholic acid (UDCA), although interactions between UDCA, gut microbes, and other bile acids are poorly understood. To gain insight into how the liver-gut-microbiome axis develops in extreme prematurity and how cholestasis alters this maturation, we conducted a nested case-control study collecting 124 stool samples longitudinally from 24 preterm infants born at mean 27.2 ± 1.8 weeks gestation and 946 ± 249.6 g, half of whom developed physiologic cholestasis. Samples were analyzed by whole metagenomic sequencing, in vitro BSH enzyme activity assays optimized for low biomass fecal samples, and quantitative mass spectrometry to measure the bile acid metabolome. In extremely preterm neonates, acquisition of the secondary bile acid biosynthesis pathway and BSH genes carried by Clostridium perfringens are the most prominent features of early microbiome development. Cholestasis interrupts this developmental pattern. BSH gene abundance and enzyme activity are profoundly reduced in cholestatic neonates, resulting in decreased quantities of unconjugated bile acids. UDCA restores total fecal bile acid levels in cholestatic neonates, but this is due to a 522-fold increase in fecal UDCA. A majority of bile acids in early development are atypical positional and stereo-isomers of bile acids. We report novel associations linking isomeric bile acids and BSH activity to neonatal growth trajectories. These data highlight deconjugation of bile acids as a key microbial function that is acquired in early neonatal development and impaired by cholestasis.

Fecal Elastase in Preterm Infants to Predict Growth Outcomes.

OBJECTIVES: Preterm infants are born functionally pancreatic insufficient with decreased pancreatic production of lipase and proteases. Developmental pancreatic insufficiency (PI) may contribute to reduced nutrient absorption and growth failure. We sought to determine longitudinal fecal elastase (ELA1) levels in a cohort of preterm infants and whether levels are associated with growth outcomes. METHODS: Prospective observational study of 30 infants 24-34 weeks gestational age and birth weight ≤1250 g fed the exclusive human milk diet, consisting of human milk with human milk-based fortifier. ELA1 was quantified by ELISA during the first 2 weeks of life [Early; 7.5 ± 1.8 days of life (DOL)] and after attainment of full, fortified feedings (Late; 63.6 ± 24.1 DOL). RESULTS: Early ELA1 levels were 192.2 ± 96.4 µg/g, and Late ELA1 levels were 268.0 ± 80.3 µg/g, 39.4% higher (P = 0.01). Infants with early PI (ELA1 < 200 µg/g) were more likely male and of lower gestational age, weight, length, and head circumference at birth. These variables, but not PI status, independently predicted somatic growth. CONCLUSIONS: Fecal ELA1 in preterm infants fed exclusive human milk diet increases with postnatal age. Although pancreatic function in preterm infants may serve as a biological contributor to early postnatal growth failure, additional studies using fecal ELA1 as a predictive biomarker for growth failure are needed in larger cohorts.

Evaluation of the Neonatal Sequential Organ Failure Assessment and Mortality Risk in Preterm Infants with Necrotizing Enterocolitis.

INTRODUCTION: The neonatal sequential organ failure assessment (nSOFA) score is a tool for calculating mortality risk of infants in the neonatal intensive care unit. The utility of the nSOFA in determining the risk of mortality or the association with surgical intervention among infants with necrotizing enterocolitis (NEC) has not been investigated. METHODS: We performed a retrospective, cohort study of preterm (<37 weeks) infants with NEC Bell's stage ≥ IIA at six hospitals from 2008 to 2020. An nSOFA score (range 0-15) was assigned to each patient at nine time points from 48 h before or after clinical illness was suspected. RESULTS: Of the 259 infants, nSOFA scores for infants who died (n = 39) or had the composite outcome of surgery or death (n = 114) were significantly higher (p < 0.05) early in the NEC course compared to nSOFA scores for infants who survived medical NEC. Twelve hours after evaluation, the area under the receiver operating characteristic curve was 0.87 (95% confidence interval [CI], 0.80-0.93) to discriminate for mortality and 0.84 (95% CI, 0.79-0.90) for surgery or death (p < 0.001). A maximum nSOFA score of ≥4 at -6, 0, 6, or 12 h following evaluation was associated with a 20-fold increase in mortality and 19-fold increase in surgery or death compared with a score of <4 (p < 0.001). CONCLUSION: In this multicenter cohort, the nSOFA score was able to discriminate well for death as well as surgery or death among infants with NEC. The nSOFA is a clinical research tool that may be used in infants with NEC to improve classification by objective quantification of organ dysfunction.

Percent mother's own milk feedings for preterm neonates predicts discharge feeding outcomes.

INTRODUCTION: No studies have determined if there is a threshold whereby use of mother's own milk (MOM) during hospitalization predicts exclusive MOM feeding at discharge. METHODS: Among 113 very low birthweight neonates, the ratio of MOM to enteral feeds was measured in the first 14 days, 28 days, and overall hospital stay. The primary outcome was exclusive MOM feeding at discharge. RESULTS: For every 1% increase in MOM consumption in the first 14 and 28 days, the odds of being discharge home on an exclusive MOM diet increased nearly 7-fold (OR 7.01, 95% CI: 2.09-23.50) and 17-fold (OR 17.46, 95% CI 4.67-63.31), respectively. A threshold of >50%, >83%, and >85% MOM consumption compared to overall enteral feeds in the first 14 days, 28 days, and throughout hospitalization, respectively, is recommended. CONCLUSIONS: Promotion of MOM consumption in the first 2-4 weeks is of paramount importance, with negligible impact of increasing MOM consumption after 28 days.

Optimizing Delivery of Breast Milk for Premature Infants: Comparison of Current Enteral Feeding Systems.

BACKGROUND: Incomplete delivery of fat from expressed breast milk (EBM) during enteral feeding to premature neonates remains a significant problem. Feeding system manufacturers have introduced changes to the enteral syringe design to improve fat delivery that have not yet been evaluated in the literature. METHODS: This study compares percentage delivery of fat from EBM using 2 major enteral feeding systems in various configurations with silicone and polyurethane tubing material and ENFit and Legacy connection systems at 3 clinically relevant infusion rates. RESULTS: The percent of fat delivery from EBM was significantly higher for the eccentric syringe system than the concentric system (P = 0.036) but did not vary significantly across infusion rates (P = 0.081). Silicone tubing had a significantly higher percent of fat delivery than polyurethane tubing within the eccentric syringe system (P = 0.039) but did not vary significantly across infusion rates (P = 0.105). There was no significant difference between ENFit and Legacy connectors using eccentric syringes with silicone tubing (P = 0.360). CONCLUSION: We demonstrate that changes to syringe design and tubing material are effective and improve fat delivery from EBM, which may result in improved growth and outcomes in premature infants. The eccentric syringe marginally improves fat delivery in comparison with the concentric syringe, and silicone tubing significantly improves fat delivery compared with polyurethane tubing.

Design, synthesis, and anticancer activities of novel perfluoroalkyltriazole-appended 2'-deoxyuridines.

We have focused on the C5-modification of 2'-deoxyuridine with substituted heterocycles for bioactivity, such as antiviral or anticancer activity. Herein, we report a novel class of nucleoside analogues with perfluoroalkyltriazole moiety as an anticancer drug candidate.