Extremely low birth weight (ELBW) infants have high morbidity and mortality, frequently due to invasive infections from bacteria, fungi, and viruses. The microbial communities present in the gastrointestinal tracts of preterm infants may serve as a reservoir for invasive organisms and remain poorly characterized. We used deep pyrosequencing to examine the gut-associated microbiome of 11 ELBW infants in the first postnatal month, with a first time determination of the eukaryote microbiota such as fungi and nematodes, including bacteria and viruses that have not been previously described. Among the fungi observed, Candida sp. and Clavispora sp. dominated the sequences, but a range of environmental molds were also observed. Surprisingly, seventy-one percent of the infant fecal samples tested contained ribosomal sequences corresponding to the parasitic organism Trichinella. Ribosomal DNA sequences for the roundworm symbiont Xenorhabdus accompanied these sequences in the infant with the greatest proportion of Trichinella sequences. When examining ribosomal DNA sequences in aggregate, Enterobacteriales, Pseudomonas, Staphylococcus, and Enterococcus were the most abundant bacterial taxa in a low diversity bacterial community (mean Shannon-Weaver Index of 1.02±0.69), with relatively little change within individual infants through time. To supplement the ribosomal sequence data, shotgun sequencing was performed on DNA from multiple displacement amplification (MDA) of total fecal genomic DNA from two infants. In addition to the organisms mentioned previously, the metagenome also revealed sequences for gram positive and gram negative bacteriophages, as well as human adenovirus C. Together, these data reveal surprising eukaryotic and viral microbial diversity in ELBW enteric microbiota dominated bytypes of bacteria known to cause invasive disease in these infants.

Background Oral colostrum priming (OCP) after birth in preterm infants is associated with improved weight gain and modification of the oral immuno-microbial environment. We hypothesized OCP would modify salivary immune peptides and the oral microbiota in preterm infants. Methods We conducted a prospective, randomized clinical trial to determine the effects of OCP on salivary immune peptide representation in preterm infants (<32 weeks completed gestation at birth). Saliva samples were collected prior to and after OCP. Salivary immune peptide representation was determined via mass spectroscopy. Oral microbiota representation was determined via sequencing of 16S rRNA gene. Results Neonates that received OCP (n = 48) had a 16-day reduction in the median length of hospitalization as compared to infants that did not receive OCP (n = 51). No differences in salivary immune peptide sequence representation prior to OCP between groups were found. Longitudinal changes in peptides were detected (lysozyme C, immunoglobulin A, lactoferrin) but were limited to a single peptide difference (alpha defensin 1) between primed and unprimed infants after OCP. We found no difference in microbial diversity between treatment groups at any time point, but diversity decreased significantly over time in both groups. OCP treatment marginally modified oral taxa with a decline in abundance of Streptococci in the OCP group at 30 days of life. Conclusions OCP had neither an effect on the salivary peptides we examined nor on overall oral bacterial diversity and composition. Infants that received OCP had a reduced length of hospitalization and warrants further investigation.

Breast milk contains a rich microbiota composed of viable skin and non-skin bacteria. The extent of the breast milk microbiota diversity has been revealed through new culture-independent studies using microbial DNA signatures. However, the extent to which the breast milk microbiota are transferred from mother to infant and the function of these breast milk microbiota for the infant are only partially understood. Here, we appraise hypotheses regarding the formation of breast milk microbiota, including retrograde infant-to-mother transfer and enteromammary trafficking, and we review current knowledge of mechanisms determining the extent of breast milk microbiota transfer from mother to infant. We highlight known functions of constituents in the breast milk microbiota?to enhance immunity, liberate nutrients, synergize with breast milk oligosaccharides to enhance intestinal barrier function, and strengthen a functional gut?brain axis. We also consider the pathophysiology of maternal mastitis with respect to a dysbiosis or abnormal shift in the breast milk microbiota. In conclusion, through a complex, highly evolved process in the early stages of discovery, mothers transfer the breast milk microbiota to their infants to impact infant growth and development.

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The benefits of antenatal glucocorticoids are now firmly established in the perinatal management of threatened preterm birth. Postnatal glucocorticoid therapy, however, remains controversial in neonatal medicine, with the need to balance short-term physiological benefits against the potential for long-term adverse consequences. This review focuses on the vascular effects of prenatal and postnatal glucocorticoids, synthesizing data from both experimental animal models and human infants with the goal of better appreciation of the short and long-term effects of these commonly used drugs. Due to their widespread and varied use, improved understanding of the cellular and molecular impact of glucocorticoids is important in guiding current practice and future research.

Objective To characterize the relationship between the duration of antibiotic administration during the first week of life and subsequent growth velocity during hospitalization. Study Design This was a retrospective study comparing the inhospital growth of infants born between 30 and 326/7 weeks' gestational age (GA) admitted to the Montefiore Weiler and Wakefield neonatal intensive care units between January 2009 and December 2015. Antibiotic duration during the first week of life was classified as no antibiotics, <5 days of antibiotics, or ≥5 days of antibiotics. Differences between discharge and birth weight Z-scores were compared between the three groups using analysis of variance. Results Of the infants, 87% received antibiotics during the first week of life, with 16% of infants completing ≥5 days. Compared with infants receiving ≤ 5 days of antibiotics, infants treated with ≥5 days had a lower GA, lower Apgar scores, more invasive respiratory support, longer duration of total parenteral nutrition, delayed initiation of enteral feeding, and a higher weight Z-score on admission and discharge (p < 0.05). However, there was no distinction in growth between the three groups assessed by the difference between admission and discharge weight Z-scores (p = 0.64), growth velocity (gram/kilogram/day) (p = 0.104), or an exponential growth velocity outcome (p = 0.423). Conclusion Early antibiotic exposure was not associated with increased growth velocity between birth and discharge. Our study was limited by its retrospective nature and lack of follow-up data postdischarge.

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Objective Our objective was to determine if the duration off respiratory support prior to discharge home from the neonatal intensive care unit (NICU) would impact hospital readmission rates among extremely low gestational age neonates (ELGAN). Study Design In this retrospective chart review, we examined readmission rates for ELGAN admitted to the Montefiore–Weiler NICU between 2013 and 2015. Results Of 140 infants born at <29 weeks' gestational age, 30 (21%) of these infants were subsequently readmitted within 90 days, primarily for respiratory complaints. Readmitted infants were born at an earlier gestational age (median = 26 weeks; interquartile range [IQR]: 24–27 weeks) compared to infants who did not require readmission (median = 27 weeks; IQR: 25-28 weeks), p = 0.03. Birth weights were smaller among infants who required readmission, 800 ± 248 g compared to 910 ± 214 g (p = 0.02). Infants with Hispanic ethnicity and those discharged during the spring season were likely to be readmitted. Duration off respiratory support prior to discharge did not predict 90-day readmission rates. Lower gestational age and birth weight were associated with higher rates of readmissions after NICU discharge. Conclusion Duration off and invasiveness of respiratory support prior to discharge did not predict risk of 90-day readmission nor did discharge during months with traditionally higher prevalence of respiratory viruses.