Antibiotic exposure prevents acquisition of beneficial metabolic functions in the preterm infant gut microbiome

Influence of infant microbiome on health and development

The microbiome is a complex ecosystem comprising microbes, their genomes, and the surrounding environment. The microbiome plays a critical role in early human development, including maturation of the host immune system and gastrointestinal tract. Multiple factors, including diet, anti-biotic use, and other environmental exposures, influence the establishment of the microbiome during infancy. Numerous studies have identified associations between the microbiome and neonatal diseases, including necrotizing enterocolitis, sepsis, and malnutrition. Furthermore, there is compelling evidence that perturbation of the microbiome in early life can have lasting developmental effects that increase an individual's risk for immune and metabolic diseases in later life. Supplementation of the microbiome with probiotics reduces the risk of necrotizing enterocolitis and sepsis in at-risk infants. This review focuses on the structure and function of the infant microbiome, the environmental and clinical factors that influence its assembly, and its impact on infant health and development.

An update on the current understanding of the infant skin microbiome and research challenges

Multiple factors contribute to establishment of skin microbial communities in early life, with perturbations in these ecosystems impacting health. This review provides an update on methods used to profile the skin microbiome and how this is helping enhance our understanding of infant skin microbial communities, including factors that influence composition and disease risk. We also provide insights into new interventional studies and treatments in this area. However, it is apparent that there are still research bottlenecks that include overreliance on high-income countries for skin microbiome 'surveys', many studies still focus solely on the bacterial microbiota, and also technical issues related to the lower microbial biomass of skin sites. These points link to pertinent open-research questions, such as how the whole infant skin microbiome interacts and how microbial-associated functions shape infant skin health and immunity.

Intestinal permeability in patients undergoing stem cell transplantation correlates with systemic acute phase responses and dysbiosis

Intestinal permeability may correlate with adverse outcomes during hematopoietic stem cell transplantation (HSCT), but longitudinal quantification with traditional oral mannitol and lactulose is not feasible in HSCT recipients because of mucositis and diarrhea. A modified lactulose:rhamnose (LR) assay is validated in children with environmental enteritis. Our study objective was to quantify peri-HSCT intestinal permeability changes using the modified LR assay. The LR assay was administered before transplant, at day +7 and +30 to 80 pediatric and young adult patients who received allogeneic HSCT. Lactulose and rhamnose were detected using urine mass spectrometry and expressed as an L:R ratio. Metagenomic shotgun sequencing of stool for microbiome analyses and enzyme-linked immunosorbent assay analyses of plasma lipopolysaccharide binding protein (LBP), ST2, REG3α, claudin1, occludin, and intestinal alkaline phosphatase were performed at the same timepoints. L:R ratios were increased at day +7 but returned to baseline at day +30 in most patients (P = .014). Conditioning regimen intensity did not affect the trajectory of L:R (P = .39). Baseline L:R ratios did not vary with diagnosis. L:R correlated with LBP levels (r2 = 0.208; P = .0014). High L:R ratios were associated with lower microbiome diversity (P = .035), loss of anaerobic organisms (P = .020), and higher plasma LBP (P = .0014). No adverse gastrointestinal effects occurred because of LR. Intestinal permeability as measured through L:R ratios after allogeneic HSCT correlates with intestinal dysbiosis and elevated plasma LBP. The LR assay is well-tolerated and may identify transplant recipients who are more likely to experience adverse outcomes.

Antibiotic Consumption, Illness, and Maternal Sensitivity in Infants with a Disorganized Attachment

Prior research found an association between mother-infant attachment and antibiotic use. Ambivalent-attached infants are more likely to take antibiotics than other infants, and their mothers tend to be less sensitive to their needs than most. This finding is important because it shows the association between psychological processes, early relationships, and health outcomes. We aim to learn about children with high-risk attachment relationships, such as disorganized-attached infants. This study compares antibiotic use, infant-mother interactive behavior, and health indicators according to infant attachment patterns (including disorganized attachment). For this purpose, we observed mothers-infants' interactive behavior in free play at nine months and infants' attachment in the Ainsworth Strange Situation at twelve months. Participants included 77 girls and 104 boys (full-term and preterm) and their mothers. Paradoxically, mothers of disorganized-attached infants reported that their children were ill only 1.56 times on average, but 61% of their children used antibiotics in the first nine months. The other mothers reported that their children were sick 5.73 times on average, but only 54% of their children used antibiotics in the same period. Infants with disorganized attachment had mothers who were more literate and less sensitive. These results add to a body of research that shows that early high-risk relationships affect children's lives at multiple levels.

Restrictive Use of Empirical Antibiotics Is Associated with Improved Short Term Outcomes in Very Low Birth Weight Infants: A Single Center, Retrospective Cohort Study from China

Antibiotics are essential for treating neonatal sepsis, but abuse or inappropriate use of antibiotics have harmful adverse effects. The inappropriate use of antibiotics has led to the significant increase in bacterial antimicrobial resistance in the neonatal intensive care unit (NICU). The aim of this study was to retrospectively analyze the changes in antibiotic usages in a NICU after the implementation of an antibiotic stewardship program and to determine the impact of this implementation on the short-term clinical outcomes of very low birth weight (VLBW) infants. The antibiotic stewardship program was initiated in the NICU in early 2015. For analysis, all eligible VLBW infants born from 1 January 2014 to 31 December 2016 were enrolled, and we classified the year 2014 as pre-stewardship, 2015 as during stewardship, and 2016 as post-stewardship. A total of 249 VLBW infants, including 96 cases in the 2014 group, 77 cases in the 2015 group, and 76 cases in the 2016 group, were included for final analysis. Empirical antibiotics were used in over 90% of VLBW infants in all three groups during their NICU stay. Over the 3-year period, the duration of an initial antibiotic course was significantly reduced. The proportion of patients receiving an initial antibiotic course for ≤3 days gradually increased (2.1% vs. 9.1% vs. 38.2%, p < 0.001), while the proportion of babies treated with an initial antibiotic course >7 days significantly decreased (95.8% vs. 79.2% vs. 39.5%, p < 0.001). The total days of antibiotic usage during the entire NICU stay also showed a significant reduction (27.0 vs. 21.0 vs. 10.0, p < 0.001). After adjusting for confounders, the reduction in antibiotic usage was associated with decreased odds of having an adverse composite short-term outcome (aOR = 5.148, 95% CI: 1.598 to 16.583, p = 0.006). To assess the continuity of antibiotic stewardship in the NICU, data from 2021 were also analyzed and compared to 2016. The median duration of an initial antibiotic course further decreased from 5.0 days in 2016 to 4.0 days in 2021 (p < 0.001). The proportion of an initial antibiotic course in which antibiotics were used for ≤3 days increased (38.2% vs. 56.7%, p = 0.022). Total antibiotic usage days during the entire NICU stay also decreased from 10.0 days in 2016 to 7.0 days in 2021 (p = 0.010). The finding of this study strongly suggests that restricting antibiotic use in VLBW infants is beneficial and can be achieved safely and effectively in China.

Early antibiotics and risk for necrotizing enterocolitis in premature infants: A narrative review

While prompt initiation of antibiotics at birth due to concerns for early onset sepsis is common, it often leads to many preterm infants being exposed to treatment despite negative blood cultures. Such exposure to early antibiotics can impact the developing gut microbiome putting infants at increased risk of several diseases. Necrotizing enterocolitis (NEC), a devastating inflammatory bowel disease that affects preterm infants, is among the most widely studied neonatal disease that has been linked to early antibiotics. While some studies have demonstrated an increased risk of NEC, other studies have demonstrated seemingly contrary findings of decreased NEC with early antibiotics. Studies using animal models have also yielded differing findings of benefit vs. harm of early antibiotic exposure on subsequent NEC susceptibility. We thus sought to conduct this narrative review to help clarify the relationship between early antibiotics exposure and future risk of NEC in preterm infants. Our objectives are to: (1) summarize findings from human and animal studies that investigated the relationship between early antibiotics and NEC, (2) highlight important limitations of these studies, (3) explore potential mechanisms that can explain why early antibiotics may increase or decrease NEC risk, and (4) identify future directions for research.

The Association between Prematurity, Antibiotic Consumption, and Mother-Infant Attachment in the First Year of Life

Antibiotics have individual and public-health drawbacks. Nevertheless, mother-infant attachment quality and maternal sensitivity are associated with antibiotic use. Ambivalent-attached infants are more likely to consume antibiotics than other infants. Conceivably, the emotional over-externalization of ambivalent-attached infants and maternal anxiety when infants are ill raise concerns in healthcare professionals, leading to antibiotic over-prescriptions. However, because infants prematurely born, particularly those with less than 32 weeks of gestation, are under more accurate health vigilance, the impact of infant and maternal behavior on antibiotic prescription may vanish in this sample. To test this hypothesis, we performed a longitudinal study to compare antibiotic use and the quality of mother-infant attachment in three groups: 86 infants born at full-term, 44 moderate-to-late preterm infants (32-36 gestation weeks), and 58 very-to-extreme preterm infants (<32 gestation weeks). Infants' attachment was observed with the Ainsworth Strange Situation's experimental paradigm at 12 months of corrected age. Findings indicate that infant attachment strategy is associated with antibiotics uptake, but results vary across samples. The proportion of infants that used antibiotics is highest among ambivalent-attached infants in the full-term sample but highest among avoidant-attached infants in the very-to-extreme premature sample. Moreover, higher infant gestational age and lower maternal sensitivity determine higher antibiotic use.