Perinatal antibiotic exposure of neonates in Canada and associated risk factors: a population-based study

Exposure to prescribed medication in early life and impacts on gut microbiota and disease development

The gut microbiota during early life plays a crucial role in infant development. This microbial-host interaction is also essential for metabolism, immunity, and overall human health in later life. Early-life pharmaceutical exposure, mainly referring to exposure during pregnancy, childbirth, and infancy, may change the structure and function of gut microbiota and affect later human health. In this Review, we describe how healthy gut microbiota is established in early life. We summarise the commonly prescribed medications during early life, including antibiotics, acid suppressant medications and other medications such as antidepressants, analgesics and steroid hormones, and discuss how these medication-induced changes in gut microbiota are involved in the pathological process of diseases, including infections, inflammatory bowel disease, metabolic diseases, allergic diseases and neurodevelopmental disorders. Finally, we review some critical methods such as dietary therapy, probiotics, prebiotics, faecal microbiota transplantation, genetically engineered phages, and vagus nerve stimulation in early life, aiming to provide a new strategy for the prevention of adverse health outcomes caused by prescribed medications exposure in early life.

Associations of intrapartum antibiotics and growth, atopy, gastrointestinal and sleep outcomes at one year of age

BACKGROUND

Studies investigating neonatal outcomes following intrapartum antibiotic exposure show conflicting results.

METHODS

Data were collected prospectively in pregnancy to 1-year-of-age, from 212 mother-infant pairs. Adjusted multivariable regression models estimated relationships following exposure to intrapartum antibiotics among vaginally-born, full-term infants and outcomes related to growth, atopic disease, gastrointestinal symptoms, and sleep at 1-year.

RESULTS

Intrapartum antibiotic exposure (n = 40) was not associated with mass, ponderal index, BMI z-score (1- year), lean mass index (5-months) or height. Antibiotic exposure in labour ≥4-h was associated with increase in fat mass index at 5-months (β 0.42 [95% CI: 0.03, 0.80], p = 0.03). Intrapartum antibiotic was associated with atopy in the first year (OR: 2.93 [95% CI: 1.34, 6.43], p = 0.007). Antibiotic exposure during intrapartum or day 1-7 was associated with newborn fungal infection requiring antifungal therapy (OR 3.04 [95% CI: 1.14, 8.10], p = 0.026), and number of fungal infections (IRR: 2.90 [95% CI: 1.02, 8.27], p = 0.046).

CONCLUSION

Intrapartum and early life exposure to antibiotics were independently associated with measures of growth, atopy, and fungal infections suggesting that intrapartum and early neonatal antibiotics be used prudently following careful risk-benefit analysis.

IMPACT

This prospective study: Shows a shift in fat mass index at 5 months associated with antibiotic administration ≥4 h in labour; an earlier age than previously reported; Shows atopy reported less frequently among those not exposed to intrapartum antibiotics; Supports earlier research of increased likelihood of fungal infection following exposure to intrapartum or early-life antibiotics; Adds to growing evidence that antibiotics used intrapartum and in early neonatal periods influence longer-term outcomes for infants. Suggests that use of intrapartum and early neonatal antibiotics should be used prudently after careful consideration of risk and benefit.

Quality Improvement Through Nurse-initiated Kaiser Sepsis Calculator at a County Hospital

BACKGROUND AND OBJECTIVES

Suspected early onset sepsis drives most antibiotic use in the newborn nursery. The Kaiser Sepsis Calculator (KSC) is a validated tool that safely decreases laboratory evaluation and antibiotic administration in infants aged ≥34 weeks. Our quality improvement aim was a nurse-initiated, KSC-based program to decrease blood cultures (BCx) and complete blood counts (CBC) by 10% from March 2021 to October 2021 among chorioamnionitis-exposed infants born ≥35 weeks' gestation. A secondary aim was to decrease antibiotic administration by 10%.

METHODS

The KSC was implemented for infants at University Health, a county hospital affiliate of the University of Texas Health Science Center San Antonio, with a level I nursery and level IV NICU. The multidisciplinary project included pediatric hospitalists, neonatologists, family practitioners, maternal-fetal medicine physicians, fellows, residents, and nurses. All infants born 6 months before (August 2020-January 2021) and 7 months after protocol implementation (March 2021-September 2021) were analyzed.

RESULTS

A total of 53 chorioamnionitis-exposed infants were included from the preintervention period and 51 from the postintervention period. CBC utilization decreased from 96% to 27%, BCx utilization decreased from 98% to 37%, and antibiotic utilization fell from 25% to 16%. In no cases were antibiotics prescribed against the KSC, and to our knowledge, no early onset sepsis diagnoses or infection-related hospital readmissions were missed.

CONCLUSIONS

The multidisciplinary implementation of the KSC led to a reduction in testing, exceeding our initial goal. A nurse-initiated protocol reduced BCx, CBC, and antibiotic utilization among chorioamnionitis-exposed infants.

Exposure to Antibiotics and Neurodevelopmental Disorders: Could Probiotics Modulate the Gut-Brain Axis?

In order to develop properly, the brain requires the intricate interconnection of genetic factors and pre-and postnatal environmental events. The gut-brain axis has recently raised considerable interest for its involvement in regulating the development and functioning of the brain. Consequently, alterations in the gut microbiota composition, due to antibiotic administration, could favor the onset of neurodevelopmental disorders. Literature data suggest that the modulation of gut microbiota is often altered in individuals affected by neurodevelopmental disorders. It has been shown in animal studies that metabolites released by an imbalanced gut-brain axis, leads to alterations in brain function and deficits in social behavior. Here, we report the potential effects of antibiotic administration, before and after birth, in relation to the risk of developing neurodevelopmental disorders. We also review the potential role of probiotics in treating gastrointestinal disorders associated with gut dysbiosis after antibiotic administration, and their possible effect in ameliorating neurodevelopmental disorder symptoms.

Prophylactic antibiotic use during labor and delivery in China: a nationwide, multicenter, hospital-based, cross-sectional study

BACKGROUND

Prophylactic antibiotic use during delivery is common in routine obstetric practice to prevent infection globally, especially in low- and middle-income countries. In China, however, little is currently known about the national estimates for prophylactic antibiotic use during delivery. Therefore, we aimed to describe the prevalence of prophylactic antibiotic use and guideline adherence using national data in China.

METHODS

This cross-sectional study analyzed a national dataset from the China Labor and Delivery Survey in 2015-2016. The primary outcomes were prophylactic antibiotic use and clinician adherence to WHO recommendations for the prevention and treatment of maternal peripartum infections. We estimated the weighted prevalence of the outcomes with Taylor series linearization and investigated the associated factors of the outcomes with logistic regression.

RESULTS

Of the 72,519 deliveries, the prevalence of antibiotic prophylaxis was 52.0%, varying from 92.8% in Shanxi to 17.3% in Hainan. The prevalence of clinician adherence to the WHO guideline was 79.9%, ranging from 93.4% in Shandong to 50.0% in Shanxi. Prophylactic antibiotic use was associated with cesarean delivery (AOR, 55.77; 95%CI, 25.74-120.86), operative vaginal delivery (AOR, 4.00; 95%CI, 1.64-9.78), preterm (AOR, 1.96; 95%CI, 1.60-2.41), premature rupture of membranes (PROM) (AOR, 2.80; 95%CI, 1.87-4.18), and meconium-stained amniotic fluid (AOR, 1.91; 95%CI, 1.30-2.81) in all deliveries and also episiotomy (AOR, 1.48; 95%CI, 1.02-2.16) in vaginal deliveries. Clinician adherence was positively associated with cesarean delivery (AOR, 5.72; 95%CI, 2.74-11.93) while negatively associated with operative vaginal delivery (AOR, 0.26; 95%CI, 0.11-0.61), PROM (AOR, 0.50; 95%CI, 0.35-0.70), and meconium-stained amniotic fluid (AOR, 0.66; 95%CI, 0.48-0.91) in all deliveries. In vaginal deliveries, clinician adherence was negatively associated with episiotomy (AOR, 0.67; 95%CI, 0.46-0.96) and severe perineal trauma (AOR, 0.09; 95%CI, 0.02-0.44). Besides, clinicians in general hospitals prescribed prophylactic antibiotics more likely (AOR, 2.79; 95%CI, 1.50-5.19) and had a lower adherence (AOR, 0.38; 95%CI, 0.20-0.71) than their peers in maternity hospitals.

CONCLUSIONS

We observed that about half of all deliveries in China received antibiotics for prophylaxis, and most deliveries were prescribed according to the WHO guideline. Furthermore, the two prevalence rates for prophylactic antibiotic use and clinician adherence varied widely across provinces of China.

Early Life Antimicrobial Exposure: Impact on Clostridioides difficile Colonization in Infants

The relationship between antibiotic use and Clostridioides difficile (C. difficile) has been well established in adults and older children but remains unclear and is yet to be fully examined in infant populations. This study aimed to determine the separate and cumulative impact from antibiotics and household cleaning products on C. difficile colonization in infants. This study included 1429 infants at 3–4 months of age and 1728 infants at 12 months of age from the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort. The levels of infant antimicrobial exposure were obtained from hospital birth charts and standardized questionnaires. Infant gut microbiota was characterized by Illumina 16S ribosomal ribonucleic acid (rRNA) gene sequencing. Analysis of C. difficile was performed using a quantitative polymerase chain reaction (qPCR). Overall, C. difficile colonized 31% and 46% of infants at 3–4 months and 12 months, respectively. At 3–4 months, C. difficile colonization was significantly higher in infants exposed to both antibiotics and higher (above average) usage of household cleaning products (adjusted odds ratio (aOR) 1.50, 95% CI 1.03–2.17; p = 0.032) than in infants who had the least antimicrobial exposure. This higher colonization persisted up to 12 months of age. Our study suggests that cumulative exposure to systemic antibiotics and higher usage of household cleaning products facilitates C. difficile colonization in infants. Further research is needed to understand the future health impacts.

Peroxymonosulfate activation by Co-doped magnetic Mn3O4 for degradation of oxytetracycline in water

Co-doped magnetic Mn₃O₄ was synthesized by the solvothermal method and adopted as an effective catalyst for the degradation of oxytetracycline (OTC) in water. Synergistic interactions between Co-Mn₃O₄ and Fe₃O₄ not only resulted in the enhanced catalytic activity through the activation of peroxymonosulfate (PMS) to degrade OTC but also made Fe₃O₄/Co-Mn₃O₄ easy to be separated and recovered from aqueous solution. 94.2% of OTC could be degraded within 60 min at an initial OTC concentration of 10 mg L^-1, catalyst dosage of 0.2 g L^-1, and PMS concentration of 10 mM. The high efficiency of OTC removal was achieved in a wider pH range of 3.0-10.0. Co (II), Co (III), Fe (II), Fe (III), Mn (II), Mn (III), and Mn (IV) on Fe₃O₄/Co-Mn₃O₄ were identified as catalytic sites based on XPS analysis. The free radical quenching experiments showed that O₂^•- radicals and ¹O₂ played the main role in the degradation process and the catalytic degradation of OTC involved both free radical and non-free radical reactions. Eventually, the intermediates of OTC degradation were examined, and the possible decomposition pathways were proposed. The excellent catalytic performances of Fe₃O₄/Co-Mn₃O₄ came from the fact that the large specific surface area could provide abundant active sites for the activation of PMS and the redistribution of inter-atomic charges accelerated the redox reactions of metal ions. The high degradation efficiency and rate constant of OTC in actual water samples indicated that Fe₃O₄/Co-Mn₃O₄ had a good practical application potential.

Changes to Gut Microbiota Following Systemic Antibiotic Administration in Infants

Long-term antibiotic use can have consequences on systemic diseases, such as obesity, allergy, and depression, implicating the causal role of gut microbiome imbalance. However, the evaluation of the effect of antibiotics in early infancy on alterations to the gut microbiome remains poorly understood. This study aimed to evaluate the gut microbiome state in infancy following systemic antibiotic treatment. Twenty infants under 3 months of age who had received antibiotics for at least 3 days were enrolled, and their fecal samples were collected 4 weeks after antibiotic administration finished. Thirty-four age-matched healthy controls without prior exposure to antibiotics were also assessed. The relative bacterial abundance in feces was obtained via sequencing of 16 S rRNA genes, and alpha and beta diversities were evaluated. At the genus level, the relative abundance of Escherichia/Shigella and Bifidobacterium increased (p = 0.03 and p = 0.017, respectively) but that of Bacteroides decreased (p = 0.02) in the antibiotic treatment group. The microbiome of the antibiotic treatment group exhibited an alpha diversity lower than that of the control group. Thus, systemic antibiotic administration in early infancy affects the gut microbiome composition even after a month has passed; long-term studies are needed to further evaluate this.

Understanding the pathways leading to gut dysbiosis and enteric environmental dysfunction in infants: the influence of maternal dysbiosis and other microbiota determinants during early life

Maternal environmental enteric dysfunction (EED) encompasses undernutrition with an inflammatory gut profile, a variable degree of dysbiosis and increased translocation of pathogens in the gut mucosa. Even though recent research findings have shed light on the pathological pathways underlying the establishment of the infant gut dysbiosis, evidence on how maternal EED influences the development of gut dysbiosis and EED in the offspring remains elusive. This review summarizes the current knowledge on the effect of maternal dysbiosis and EED on infant health, and explores recent progress in unraveling the mechanisms of acquisition of a dysbiotic gut microbiota in the offspring. In Western communities, maternal inoculum, delivery mode, perinatal antibiotics, feeding practices, and infections are the major drivers of the infant gut microbiota during the first two years of life. In other latitudes, the infectious burden and maternal malnutrition might introduce further risk factors for infant gut dysbiosis. Novel tools, such as transcriptomics and metabolomics, have become indispensable to analyze the metabolic environment of the infant in utero and post-partum. Human-milk oligosaccharides have essential prebiotic, antimicrobial, and anti-biofilm properties that might offer additional therapeutic opportunities.

Perinatal Penicillin Exposure Affects Cortical Development and Sensory Processing

The prevalent use of antibiotics in pregnant women and neonates raises concerns about long-term risks for children’s health, but their effects on the central nervous system is not well understood. We studied the effects of perinatal penicillin exposure (PPE) on brain structure and function in mice with a therapeutically relevant regimen. We used a battery of behavioral tests to evaluate anxiety, working memory, and sensory processing, and immunohistochemistry to quantify changes in parvalbumin-expressing inhibitory interneurons (PV+ INs), perineuronal nets (PNNs), as well as microglia density and morphology. In addition, we performed mesoscale calcium imaging to study neural activity and functional connectivity across cortical regions, and two-photon imaging to monitor dendritic spine and microglial dynamics. We found that adolescent PPE mice have abnormal sensory processing, including impaired texture discrimination and altered prepulse inhibition. Such behavioral changes are associated with increased spontaneous neural activities in various cortical regions, and delayed maturation of PV+ INs in the somatosensory cortex. Furthermore, adolescent PPE mice have elevated elimination of dendritic spines on the apical dendrites of layer 5 pyramidal neurons, as well as increased ramifications and spatial coverage of cortical microglia. Finally, while synaptic defects are transient during adolescence, behavioral abnormalities persist into adulthood. Our study demonstrates that early-life exposure to antibiotics affects cortical development, leaving a lasting effect on brain functions.

Infant gut microbiota restoration: state of the art

The gut microbiota has a central role in the programming of the host's metabolism and immune function, with both immediate and long-term health consequences. Recent years have witnessed an accumulation of understanding of the process of the colonization and development of the gut microbiota in infants. The natural gut microbiota colonization during birth is frequently disrupted due to C-section birth or intrapartum or postpartum antibiotic exposure, and consequently aberrant gut microbiota development is common. On a positive note, research has shown that restoration of normal gut microbiota development is feasible. We discuss here the current understanding of the infant microbiota, provide an overview of the sources of disturbances, and critically evaluate the evidence on early life gut microbiota restoration for improved health outcomes by analyzing published data from infant gut microbiota restoration studies.

Antibiotics at birth and later antibiotic courses: effects on gut microbiota

BACKGROUND

Intrapartum antibiotic prophylaxis (IAP) is widely used, but the evidence of the long-term effects on the gut microbiota and subsequent health of children is limited. Here, we compared the impacts of perinatal antibiotic exposure and later courses of antibiotic courses on gut microbiota.

METHODS

This was a prospective, controlled cohort study among 100 vaginally delivered infants with different perinatal antibiotic exposures: control (27), IAP (27), postnatal antibiotics (24), and IAP and postnatal antibiotics (22). At 1 year of age, we performed next-generation sequencing of the bacterial 16S ribosomal RNA gene of fecal samples.

RESULTS

Exposure to the perinatal antibiotics had a clear impact on the gut microbiota. The abundance of the Bacteroidetes phylum was significantly higher in the control group, whereas the relative abundance of Escherichia coli was significantly lower in the control group. The impact of the perinatal antibiotics on the gut microbiota composition was greater than exposure to later courses of antibiotics (28% of participants).

CONCLUSIONS

Perinatal antibiotic exposure had a marked impact on the gut microbiota at the age of 1 year. The timing of the antibiotic exposure appears to be the critical factor for the changes observed in the gut microbiota.

IMPACT

Infants are commonly exposed to IAP and postnatal antibiotics, and later to courses of antibiotics during the first year of life. Perinatal antibiotics have been associated with an altered gut microbiota during the first months of life, whereas the evidence regarding the long-term impact is more limited. Perinatal antibiotic exposure had a marked impact on the infant's gut microbiota at 1 year of age. Impact of the perinatal antibiotics on the gut microbiota composition was greater than that of the later courses of antibiotics at the age of 1 year.

The influence of early-life microbial exposures on long-term respiratory health

Host-microbiome interactions exert a profound influence on human physiology and health outcomes. In particular, certain characteristics of commensal microbiota during a critical period in early life are essential for the establishment of immune tone and metabolic control. An increasing body of evidence suggests that early life exposures that disrupt these interactions can substantially influence life-long risks for respiratory disease. Here, we explore how such early life exposures, including antibiotic exposure, maternal diet, preterm birth, mode of delivery, breastfeeding, and environmental variables shape the infant microbiome, and the mechanisms by such changes can in turn impact respiratory health.

Maternal Intrapartum Antibiotic Treatment and Gut Microbiota Development in Healthy Term Infants

OBJECTIVE

The aim of the study was to investigate the impact of intrapartum antibiotic treatment (IAT) on the compositional development of gut microbiota in healthy term infants.

STUDY DESIGN

A case-control study of 24 infants exposed to and 24 matched infants not exposed to IAT was conducted. All subjects were born by vaginal delivery at term and breastfed. None of the infants received antibiotics during the immediate neonatal period. Fecal samples were obtained at the ages of 1 and 6 months. The composition of the intestinal microbiota was assessed by 16S rRNA gene sequencing.

RESULTS

IAT was associated with reduced microbial richness but not diversity at 1 month of age. Furthermore, the relative abundances of Clostridiaceae and Erysipelotrichaceae were significantly altered in infants exposed to IAT as compared to nonexposed infants at 1 month of age. The observed deviations in gut microbiota composition between infants exposed and not exposed to IAT diminished by the age of 6 months.

CONCLUSIONS

IAT is associated with short-term perturbations in the gut microbiota development in healthy term, vaginally delivered, breastfed infants. The composition of the gut microbiota is mostly restored by the age of 6 months.

Bacteroides-dominant gut microbiome of late infancy is associated with enhanced neurodevelopment

Dysbiosis of gut microbiota has been retrospectively linked to autism spectrum disorders but the temporal association between gut microbiota and early neurodevelopment in healthy infants is largely unknown. We undertook this study to determine associations between gut microbiota at two critical periods during infancy and neurodevelopment in a general population birth cohort.Here, we analyzed data from 405 infants (199 females) from the CHILD (Canadian Healthy Infant Longitudinal Development) Cohort Study. Neurodevelopmental outcomes were objectively assessed using the Bayley Scale of Infant Development (BSID-III) at 1 and 2 years of age. Microbiota profiling with 16S rRNA gene sequencing was conducted on fecal samples obtained at a mean age of 4 and 12 months.Using clustering methods, we identified three groups of infants based on relative abundance of gut microbiota at 12 months: Proteobacteria-dominant cluster (22.4% higher abundance at 12 months), Firmicutes-dominant cluster (46.0% higher abundance at 12 months) and Bacteroidetes-dominant cluster (31.6% higher abundance at 12 months). Relative to the Proteobacteria-dominant cluster, the Bacteroidetes-dominant cluster was associated with higher scores for cognitive (4.8 points; FDRp = .02), language (4.2 points; FDRp≤0.001), and motor (3.1 points; FDRp = .03) development at age 2 in models adjusted for covariates. When stratified by sex, only male infants with a Bacteroidetes-dominant microbiota had more favorable cognitive (5.9 points, FDRp = .06) and language (7.9 points; FDRp≤0.001) development. Genus Bacteroides abundance in gut microbiota was positively correlated with cognitive and language scores at age 2. Fully adjusted linear mixed model analysis revealed a positive association between Bacteroidetes-dominant cluster and change in cognitive and language performance from 1 to 2 years, predominantly among males. No associations were evident between 4-month microbiota clusters and BSID-II scores. Noteworthy is that enhanced sphingolipid synthesis and metabolism, and antagonism or competition between Bacteroides and Streptococcus were characteristic of a Bacteroidetes-dominant gut microbiota.This study found strong evidence of positive associations between Bacteroidetes gut microbiota in late infancy and subsequent neurodevelopment, most prominently among males but not females.

Impact of Maternal Intrapartum Antibiotics, and Caesarean Section with and without Labour on Bifidobacterium and Other Infant Gut Microbiota

Background and Aims: Few studies consider the joint effect of multiple factors related to birth, delivery mode, intrapartum antibiotic prophylaxis and the onset of labour, on the abundance of Bifidobacterium and the quantity of this genus and its species Bifidobacterium longum subsp. infantis in the infant gut microbiota. We implemented such a study. Methods: Among 1654 Canadian full-term infants, the gut microbiota of faecal samples collected at 3 months were profiled by 16S rRNA sequencing; the genus Bifidobacterium and Bifidobacterium longum subsp. infantis were quantified by qPCR. Associations between Bifidobacterium and other gut microbiota were examined by Spearman’s rank correlation. Results: Following vaginal birth, maternal IAP exposure was associated with reduced absolute quantities of bifidobacteria among vaginally delivered infants (6.80 vs. 7.14 log₁₀ (gene-copies/g faeces), p < 0.05), as well as their lowered abundance relative to other gut microbiota. IAP differences in infant gut bifidobacterial quantity were independent of maternal pre-pregnancy body-mass-index (BMI), and remarkably, they were limited to breastfed infants. Pre-pregnancy BMI adjustment revealed negative associations between absolute quantities of bifidobacteria and CS with or without labour in non-breastfed infants, and CS with labour in exclusively breastfed infants. Significant correlations between Bifidobacterium abundance and other microbial taxa were observed. Conclusions: This study documented the impact of the birth mode and feeding status on the abundance of gut Bifidobacterium, and pointed to the important ecological role of the genus Bifidobacterium in gut microbiota due to its strong interaction with other gut microbiota in early infancy.

Impact of Delivery Mode on Infant Gut Microbiota

Microbial colonization of the neonate is an important feature of normal birth. The gut microbiota has a central role in the programming of the host's metabolism and immune function, with both immediate and long-term health consequences. During vaginal birth, the infant is exposed to diverse maternal microbes, of which specific faecal microbes colonize the infant's gut. C-section eliminates the infant's contact with maternal microbes, preventing vertical transmission of gut microbes. Consequently, infants are colonized by bacteria from the environment, including potential pathogens from the hospital environment. Recent studies have shown that intrapartum antibiotic exposure has a C-section-like effect on the infant gut microbiota. While the composition of the gut microbiota largely normalizes during the first year of life, epidemiological studies suggest that the aberrant early microbial exposures have long-term immunological and metabolic consequences. Because of the high prevalence of procedures that prevent normal gut microbiota development, effective methods to normalize the gut microbiota of neonates are urgently needed. Even more importantly, attention should be paid to the microbiota imbalance in C-section-born and antibiotic-exposed infants in clinical practice. Breastfeeding and probiotics are particularly important for infants with disrupted gut colonization.

The Prevalence and Factors Associated with Prophylactic Antibiotic Use during Delivery: A Hospital-Based Retrospective Study in Palembang, Indonesia

Prophylactic antibiotic usage during delivery is a common practice worldwide, especially in low- to middle-income countries. Guidelines have been published to reduce antibiotic overuse; however, data describing the use of prophylactic antibiotics and clinician adherence to guidelines in low- to middle-income countries remain limited. This study aimed to describe the prevalence of prophylactic antibiotic use, factors associated with its use, and clinician adherence to guidelines. A retrospective review was conducted for all deliveries from 1 January 2016 to 31 December 2018 at a tertiary level hospital in Indonesia. The prevalence of prophylactic antibiotic use during delivery was 47.1%. Maternal education level, Ob/Gyn specialist-led delivery, a history of multiple abortions, C-section, premature membrane rupture, and antepartum hemorrhage were independently associated with prophylactic antibiotic use. Clinician adherence to the guidelines was 68.9%. Adherence to guidelines was the lowest in conditions where the patient had only one indication for prophylactic antibiotics (aOR 0.36, 95% CI 0.24-0.54). The findings showed that the prevalence of prophylactic antibiotic use during delivery was moderate to high. Adherence to local guidelines was moderate. Updating the local prescribing guidelines may improve clinician adherence.

Priming for Life: Early Life Nutrition and the Microbiota-Gut-Brain Axis

Microbes colonize the human body during the first moments of life and coexist with the host throughout the lifespan. Intestinal microbiota and their metabolites aid in the programming of important bodily systems such as the immune and the central nervous system during critical temporal windows of development, with possible structural and functional implications throughout the lifespan. These critical developmental windows perinatally (during the first 1000 days) are susceptible timepoints for insults that can endure long lasting effects on the microbiota-gut-brain axis. Environmental and parental factors like host genetics, mental health, nutrition, delivery and feeding mode, exposure to antibiotics, immune activation and microbiota composition antenatally, are all factors that are able to modulate the microbiota composition of mother and infant and may thus regulate important bodily functions. Among all these factors, early life nutrition plays a pivotal role in perinatal programming and in the modulation of offspring microbiota from birth throughout lifespan. This review aims to present current data on the impact of early life nutrition and microbiota priming of important bodily systems and all the factors influencing the microbial coexistence with the host during early life development.

Neonatal antibiotic exposure impairs child growth during the first six years of life by perturbing intestinal microbial colonization

Exposure to antibiotics in the first days of life is thought to affect various physiological aspects of neonatal development. Here, we investigate the long-term impact of antibiotic treatment in the neonatal period and early childhood on child growth in an unselected birth cohort of 12,422 children born at full term. We find significant attenuation of weight and height gain during the first 6 years of life after neonatal antibiotic exposure in boys, but not in girls, after adjusting for potential confounders. In contrast, antibiotic use after the neonatal period but during the first 6 years of life is associated with significantly higher body mass index throughout the study period in both boys and girls. Neonatal antibiotic exposure is associated with significant differences in the gut microbiome, particularly in decreased abundance and diversity of fecal Bifidobacteria until 2 years of age. Finally, we demonstrate that fecal microbiota transplant from antibiotic-exposed children to germ-free male, but not female, mice results in significant growth impairment. Thus, we conclude that neonatal antibiotic exposure is associated with a long-term gut microbiome perturbation and may result in reduced growth in boys during the first six years of life while antibiotic use later in childhood is associated with increased body mass index.

Bovine Lactoferrin Supplementation Does Not Disrupt Microbiota Development in Preterm Infants Receiving Probiotics

OBJECTIVE

The aim of the study was to assess whether bovine lactoferrin (bLf) supplementation disrupts intestinal microbiota development in preterm infants less than 31 weeks gestational age receiving prophylactic probiotic administration.

METHODS

Subjects were recruited from the LACUNA trial (ISRCTN66482337), designed to assess bLf safety. These subjects were randomized to daily receive either probiotic supplements or probiotics supplemented with 100 mg bLf mixed with their feeds (human milk or formula). Stools were collected weekly from enrolled infants for 1 month and the microbiota characterized using V6-16S rRNA gene amplicon profiling.

RESULTS

Infants' microbiomes did not increase in alpha diversity over time in both feeding interventions. Infants receiving bLf supplementation had overall higher species richness as compared with those not receiving these supplements and lactoferrin supplementation had differing effects on infant microbiota species richness depending on the infant's gestational age. Principal co-ordinate analysis revealed that the infant microbiotas did not separate by intervention group, gestational age bracket at birth or sampling time and the main factor dictating sample clustering was infant identity. There were very few detectable differences in taxa relative abundance or functional gene content between the microbiotas in the 2 study groups.

CONCLUSIONS

Bovine lactoferrin supplementation has minimal impact on microbiota composition/function in preterm infants receiving probiotics, and therefore, is unlikely to disrupt microbiota development.

Impaired Hypothalamic Microglial Activation in Offspring of Antibiotic-Treated Pregnant/Lactating Rats Is Attenuated by Prebiotic Oligofructose Co-Administration

Microbial colonization of the gut early in life is crucial for the development of the immune and nervous systems, as well as influencing metabolism and weight gain. While early life exposure to antibiotics can cause microbial dysbiosis, prebiotics are non-digestible substrates that selectively promote the growth of beneficial gut microbiota. Our objective was to examine the effects of dietary prebiotic administration on the consequences of maternal antibiotic intake on offspring body weight, behavior, and neuroimmune responses later in life. Sprague-Dawley rat dams were given low-dose penicillin (LDP), prebiotic fiber (10% oligofructose), or both, during the third week of pregnancy and throughout lactation. Anxiety-like behavior, weight gain, body composition, cecal microbiota composition, and microglial responses to lipopolysaccharide (LPS) were assessed in offspring. Male and female prebiotic offspring had lower body weight compared to antibiotic offspring. Maternal antibiotic exposure resulted in lasting effects on select offspring microbiota including a lower relative abundance of Streptococcus, Lactococcus, and Eubacterium at 10 weeks of age. Maternal antibiotic use impaired microglial response to LPS in the hypothalamus compared to control, and this phenotype was reversed with prebiotic. Prebiotic fiber warrants further investigation as an adjunct to antibiotic use during pregnancy.

Postnatal pediatric systemic antibiotic episodes during the first three years of life are not associated with mode of delivery

BACKGROUND

Delivery by cesarean section (C-section) is associated with adverse short-term and long-term infant outcomes. Given that antibiotics during early life are prescribed for infant outcomes that are more likely among c-section deliveries, we hypothesized that postnatal antibiotic exposure will be greater among c-section infants compared to vaginally delivered infants.

OBJECTIVE

The aim of this paper was to evaluate if mode of infant delivery was associated with patterns of systemic antibiotic exposure in children during their first three years.

METHODS

Pediatric electronic health records from UFHealth, 2011 to 2017 were reviewed. We included singleton, term infants (37-42 weeks gestation) with a birth weight ≥ 2500 grams, with documented mode of delivery and well visits on record. Infants with a neonatal intensive care unit stay were excluded. Both oral and intravenous antibiotics for a 10-day duration were classified as a single episode. The primary outcome was antibiotic episodes in the first three years of life, and a sub-analysis was performed to compare broad-spectrum versus narrow-spectrum antibiotic exposures.

RESULTS

The mean number of antibiotic episodes in 4,024 full-term infants was 0.34 (SD = 0.79) and 24.1% of infants had at least one antibiotic episode. Penicillins were the most prescribed antibiotic in children 0-1 years (66.9%) and cephalosporins were the most common antibiotic prescribed for children 1-3 years (56.2%). We did not detect a meaningful or significant rate ratio (RR) between mode of delivery and overall antibiotic episodes 1.14 (95% CI 0.99, 1.31), broad-spectrum episodes 1.19 (95% CI 0.93, 1.52, or narrow-spectrum episodes 1.14 (95% CI 0.97, 1.34).

CONCLUSION

Our results do not support the hypothesis that postnatal antibiotic exposure was greater among infants delivered by cesarean section compare to infants delivered vaginally during the first three years of life.

Effect of intrapartum antibiotics on the intestinal microbiota of infants: a systematic review

INTRODUCTION

The use of intrapartum antibiotic prophylaxis (IAP) has become common practice in obstetric medicine and is used in up to 40% of deliveries. Despite its benefits, the risks associated with exposing large numbers of infants to antibiotics, especially long-term effects on health through changes in the microbiota, remain unclear. This systematic review summarises studies that have investigated the effect of IAP on the intestinal microbiota of infants.

METHODS

A systematic search in Ovid MEDLINE was used to identify original studies that investigated the effect of IAP on the intestinal microbiota in infants. Studies were excluded if: they included preterm infants, the antibiotic regimen was not specified, antibiotics were used for indications other than prophylaxis, probiotics were given to mothers or infants, or antibiotics were given to infants.

RESULTS

We identified six studies, which investigated a total of 272 infants and included 502 stool samples collected up to 3 months of age. In all the studies, IAP was given for group B streptococcus (GBS) colonisation. Infants who were exposed to GBS IAP had a lower bacterial diversity, a lower relative abundance of Actinobacteria, especially Bifidobacteriaceae, and a larger relative abundance of Proteobacteria in their intestinal microbiota compared with non-exposed infants. Conflicting results were reported for the phyla Bacteroidetes and Firmicutes.

CONCLUSIONS

GBS IAP has profound effects on the intestinal microbiota of infants by diminishing beneficial commensals. Such changes during the early-life 'critical window' during which the intestinal microbiota and the immune response develop concurrently may have an important influence on immune development. The potential long-term adverse consequences of this on the health of children warrant further investigation.

Quality of the Clinical Maternal and Neonatal Healthcare Assessment in a Tertiary Public Maternity Hospital in R. Macedonia

INTRODUCTION

Maternal and neonatal infections can be prevented, but they are still common in low and middle-developed countries. There is a connection between childbirth on one hand and postpartum and newborn care on the other. Globally, several efforts are being made to improve quality of childbirth by providing initial assessment of procedures, risk prevention and continuous monitoring of childbirth process and possible complications. The World Health Organization has developed Checklists for Safe Delivery with procedures to be implemented as routine care, in order to promptly detect and manage complications related to childbirth.

MATERIAL AND METHODS

A retrospective study was conducted in the University Clinic of Gynecology and Obstetrics in Skopje, a maternity hospital in R. Macedonia from the tertiary level of the public health care system. In this study 300 obstetric and 307 neonatal histories from childbirths in February and March 2018 have been analyzed. The collected data refers to the care of the prepartum, intrapartum, early postpartum and early neonatal periods.

RESULTS

An initial assessment at admission proved that 14.7% of pregnant women had existing infection, in 93% of them the body temperature was measured and in only 9.3% urine analysis was made, 10.3% of the women had arterial hypertension, and 66.5% of them with hypertension had a headache. In the continuous monitoring and prevention of potential risk, arterial tension was measured in 33% of all mothers. In all women the placenta quality was checked up, as well as vaginal bleeding, application of oxytocin and hemoglobin level before discharge.

CONCLUSION

The quality and quantity of documented data in the maternity hospital medical histories is high. There were no standard protocols for assessment of pregnant women. Certain procedures are conducted in every woman during childbirth. Standardized procedures are needed to be applied during every childbirth.

Neonatal Exposure to Amoxicillin Alters Long-Term Immune Response Despite Transient Effects on Gut-Microbiota in Piglets

Antibiotic exposure during neonatal development may result in transient or persistent alterations of key microbes that are vital for normal development of local and systemic immunity, potentially impairing immune competence later in life. To further elucidate the relationship between antibiotic exposure and immune development, newborn pigs were exposed to a therapeutic pediatric dose (30 mg/kg/day) of amoxicillin (AB) or placebo (PL) from post-natal day (PND) 0–14. Subsequently, immune cell phenotype, microbial composition, and immune response to an intraperitoneal (IP) challenge with Salmonella enterica serovar Typhimurium were evaluated. AB exposure caused significant changes in fecal microbial composition on PND 3 (P = 0.025). This stemmed from a 2-fold increase in Enterobacteriaceae with live cecal coliforms on PND 7 indicating at 10-fold increase (P = 0.036). Alterations in microbial composition were transient, and successional patterns were normalizing by PND 14 (P = 0.693). Differences in PBMC (peripheral blood mononuclear cell) immune cell subtypes were detected, with the percentage of CD3⁺CD4⁺ T cells among the broader T cell population (CD3⁺CD4⁺/CD3⁺) being significantly higher (P = 0.031) in AB pigs and the numbers of CD4+CD45RA+ (naïve) T cells per liter of blood were lower on PND 21 in AB pigs (P = 0.036). Meanwhile, PBMCs from AB pigs produced significantly more IFNγ upon stimulation with a T-cell mitogen on PND 21 and 49 (P = 0.021). When AB pigs were challenged with heat-killed Salmonella (IP) on PND 49, IFNγ gene expression in peripheral blood was upregulated compared to those treated with PL (P = 0.043). Additionally, AB pigs showed stronger activation among neutrophils infiltrating the peritoneal cavity after in vivo immune challenge, based on higher levels of NF-κB nuclear translocation (P = 0.001). Overall, our results indicate that early life treatment with a therapeutically relevant dose of a commonly prescribed antibiotic has a programming effect on the immune system. Despite antibiotics only causing a transient disruption in gut-associated microbial communities, implications were long-term, with antibiotic treated pigs mounting an upregulated response to an immune challenge. This research adds to the growing body of evidence indicating adverse immune outcomes of early life antibiotic exposures.

Reviewing the evidence on breast milk composition and immunological outcomes

A large number of biologically active components have been found in human milk (HM), and in both human and animal models, studies have provided some evidence suggesting that HM composition can be altered by maternal exposures, subsequently influencing health outcomes for the breastfed child. Evidence varies from the research studies on whether breastfeeding protects the offspring from noncommunicable diseases, including those associated with immunological dysfunction. It has been hypothesized that the conflicting evidence results from HM composition variations, which contain many immune active molecules, oligosaccharides, lactoferrin, and lysozyme in differing concentrations, along with a diverse microbiome. Determining the components that influence infant health outcomes in terms of both short- and long-term sequelae is complicated by a lack of understanding of the environmental factors that modify HM constituents and thereby offspring outcomes. Variations in HM immune and microbial composition (and the differing infantile responses) may in part explain the controversies that are evidenced in studies that aim to evaluate the prevalence of allergy by prolonged and exclusive breastfeeding. HM is a "mixture" of immune active factors, oligosaccharides, and microbes, which all may influence early immunological outcomes. This comprehensive review provides an in-depth overview of existing evidence on the studied relationships between maternal exposures, HM composition, vaccine responses, and immunological outcomes.

Specific class of intrapartum antibiotics relates to maturation of the infant gut microbiota: a prospective cohort study

OBJECTIVE

To evaluate the potential impact of intrapartum antibiotics, and their specific classes, on the infant gut microbiota in the first year of life.

DESIGN

Prospective study of infants in the New Hampshire Birth Cohort Study (NHBCS).

SETTINGS

Rural New Hampshire, USA.

POPULATION OR SAMPLE

Two hundred and sixty-six full-term infants from the NHBCS.

METHODS

Intrapartum antibiotic use during labour and delivery was abstracted from medical records. Faecal samples collected at 6 weeks and 1 year of age were characterised by 16S rRNA sequencing, and metagenomics analysis in a subset of samples.

EXPOSURES

Maternal exposure to antibiotics during labour and delivery.

MAIN OUTCOME MEASURE

Taxonomic and functional profiles of faecal samples.

RESULTS

Infant exposure to intrapartum antibiotics, particularly to two or more antibiotic classes, was independently associated with lower microbial diversity scores as well as a unique bacterial community at 6 weeks (GUnifrac, P = 0.02). At 1 year, infants in the penicillin-only group had significantly lower α diversity scores than infants not exposed to intrapartum antibiotics. Within the first year of life, intrapartum exposure to penicillins was related to a significantly lower increase in several taxa including Bacteroides, use of cephalosporins was associated with a significantly lower rise over time in Bifidobacterium and infants in the multi-class group experienced a significantly higher increase in Veillonella dispar.

CONCLUSIONS

Our findings suggest that intrapartum antibiotics alter the developmental trajectory of the infant gut microbiome, and specific antibiotic types may impact community composition, diversity and keystone immune training taxa.

TWEETABLE ABSTRACT

Class of intrapartum antibiotics administered during delivery relates to maturation of infant gut microbiota.

Management of Neonates Born at ≥35 0/7 Weeks' Gestation With Suspected or Proven Early-Onset Bacterial Sepsis

The incidence of neonatal early-onset sepsis (EOS) has declined substantially over the last 2 decades, primarily because of the implementation of evidence-based intrapartum antimicrobial therapy. However, EOS remains a serious and potentially fatal illness. Laboratory tests alone are neither sensitive nor specific enough to guide EOS management decisions. Maternal and infant clinical characteristics can help identify newborn infants who are at risk and guide the administration of empirical antibiotic therapy. The incidence of EOS, the prevalence and implications of established risk factors, the predictive value of commonly used laboratory tests, and the uncertainties in the risk/benefit balance of antibiotic exposures all vary significantly with gestational age at birth. Our purpose in this clinical report is to provide a summary of the current epidemiology of neonatal sepsis among infants born at ≥35 0/7 weeks' gestation and a framework for the development of evidence-based approaches to sepsis risk assessment among these infants.

The association between early life antibiotic use and allergic disease in young children: recent insights and their implications

INTRODUCTION

Greater prescribing of antibiotics to infants has coincided with an epidemic of allergic disease. Through meta-analytic synthesis, accumulating evidence from prospective or database cohorts suggests a link between infant antibiotic treatment and the development of atopy. Stronger associations seen with multiple course and broad-spectrum antibiotic treatment add to biological plausibility. A major bias, confounding by indication, has been addressed in studies on antibiotic treatment of conditions which do not precede allergic disease. Areas covered: Our review provides an up-to-date synthesis of the current literature on associations between infant antibiotic exposure and future allergic disease. We discuss methods that assist in reducing study bias and look at new insights from studies of the infant gut microbiome. Expert commentary: Large-scale profiling of the gut microbiome provides a new tool for disentangling biases found in observational studies of infant antibiotic use. To date, microbial dysbiosis of the infant gut has been reported to predict allergic disease independent of antibiotic exposure up to 3 months after birth. However, these studies have not accounted for antibiotic treatment in later infancy. Continued study of the infant gut microbiome, mycobiome, or resistome will provide a closer link to antibiotic treatment or refute it as a cause of allergic disease.

Prenatal antibiotic exposure and childhood asthma: a population-based study

Antibiotic use during infancy alters gut microbiota and immune development and is associated with an increased risk of childhood asthma. The impact of prenatal antibiotic exposure is unclear. We sought to characterise the association between prenatal antibiotic exposure and childhood asthma.We performed a population-based cohort study using prescription records, hospitalisation records and physician billing claims from 213 661 mother-child dyads born in Manitoba, Canada between 1996 and 2012. Associations were determined using Cox regression, adjusting for maternal asthma, postnatal antibiotics and other potential confounders. Sensitivity analyses evaluated maternal antibiotic use before and after pregnancy.36.8% of children were exposed prenatally to antibiotics and 10.1% developed asthma. Prenatal antibiotic exposure was associated with an increased risk of asthma (adjusted hazard ratio (aHR) 1.23, 95% CI 1.20-1.27). There was an apparent dose response (aHR 1.15, 95% CI 1.11-1.18 for one course; aHR 1.26, 95% CI 1.21-1.32 for two courses; and aHR 1.51, 95% CI 1.44-1.59 for three or more courses). Maternal antibiotic use during 9 months before pregnancy (aHR 1.27, 95% CI 1.24-1.31) and 9 months postpartum (aHR 1.32, 95% CI 1.28-1.36) were similarly associated with asthma.Prenatal antibiotic exposure was associated with a dose-dependent increase in asthma risk. However, similar associations were observed for maternal antibiotic use before and after pregnancy, suggesting the association is either not directly causal, or not specific to pregnancy.

The Impact of Maternal Antibiotics on Neonatal Disease

OBJECTIVES

We examined the impact of prenatal exposure to maternal antibiotics on risk of necrotizing enterocolitis (NEC), late onset sepsis (LOS), and death in infants born preterm.

STUDY DESIGN

Secondary data analysis was conducted via an extant cohort of 580 infants born <32 weeks of gestation and enrolled in 3 level III neonatal intensive care units. Prenatal antibiotic exposure was defined as antibiotics received by the mother within 72 hours before delivery. Postnatal empiric antibiotic exposure was defined as antibiotic initiated within the first day of life without documented infection, categorized as low (<5 days) or high (>5 days) duration.

RESULTS

Two-thirds of mothers received antibiotics within 72 hours before delivery, of whom 59.8% received >1 antibiotic. Ampicillin (37.6%) and azithromycin (26.4%) were the most common antibiotics given. NEC occurred in 7.5%, LOS in 11.1%, death in 9.6%, and the combined outcome of NEC, LOS, or death in 21.3% of study infants. In multiple logistic regression models adjusted for gestational age, postnatal empiric antibiotic exposure, and other factors, prenatal antibiotic exposure was associated with reduced risk of NEC (OR 0.28; 95% CI 0.14-0.56; P < .001), death (OR 0.29; 95% CI 0.14-0.60; P = .001), but not LOS (OR 1.59; 95% CI 0.84-2.99; P = .15), although protection was significant for the combined outcome (OR 0.52, P < .001). High postnatal empiric antibiotic exposure was associated with greater risk of death but not other outcomes in multiple regression models (OR 3.18, P = .002).

CONCLUSIONS

Prenatal antibiotic exposure was associated with lower rates of NEC or death of infants born preterm, and its impact on infant outcomes warrants further study.

Implementation of the Sepsis Risk Calculator at an Academic Birth Hospital

BACKGROUND

Multivariate predictive models for estimating the risk of neonatal early-onset sepsis (EOS) are available as a Web-based sepsis risk calculator (SRC) and may reduce the proportion of newborns empirically treated with antibiotics after birth. EOS risk assessment based on such models would require workflow changes at most birth hospitals.

METHODS

A multidisciplinary team of obstetric, neonatal, and information technology staff at a large, academic, birth hospital collaborated to implement the SRC. The obstetric electronic medical record was modified to provide a link to the SRC. Labor and delivery nurses calculated the sepsis risk at birth and alerted neonatal clinicians for risk estimates ≥0.7 cases per 1000 live births. Subsequent interventions were based on the risk estimate and newborn clinical examination. We compared the proportion of infants born at ≥36 weeks' gestation with laboratory testing and empirical antibiotics for risk of EOS during the 15-month periods before (n = 5692) and after (n = 6090) implementation. EOS cases were reviewed to assess for safety.

RESULTS

Empirical antibiotic use among newborns ≤72 hours old declined by 42% (6.3% to 3.7%; relative risk 0.58 [95% confidence interval, 0.50-0.69]), and laboratory testing declined by 82% (26.9% to 4.9%; relative risk 0.18 [95% confidence interval, 0.16-0.21]). The EOS incidence was not different between the study periods, and no safety concerns were identified.

CONCLUSIONS

The SRC was integrated into the workflow of a large, academic perinatal center, resulting in significant reductions in antibiotics and laboratory testing for EOS and demonstrating the potential for this approach to impact national practice.

Acquisition of extended spectrum beta-lactamase-producing enterobacteriaceae in neonates: A community based cohort in Madagascar

In low and middle income countries (LMICs), where the burden of neonatal sepsis is the highest, the spread of extended spectrum beta-lactamase-producing enterobacteriaceae (ESBL-PE) in the community, potentially contributing to the neonatal mortality, is a public health concern. Data regarding the acquisition of ESBL-PE during the neonatal period are scarce. The routes of transmission are not well defined and particularly the possible key role played by pregnant women. This study aimed to understand the neonatal acquisition of ESBL-PE in the community in Madagascar. The study was conducted in urban and semi-rural areas. Newborns were included at birth and followed-up during their first month of life. Maternal stool samples at delivery and six stool samples in each infant were collected to screen for ESBL-PE. A Cox proportional hazards model was performed to identify factors associated with the first ESBL-PE acquisition. The incidence rate of ESBL-PE acquisition was 10.4 cases/1000 newborn-days [95% CI: 8.0–13.4 cases per 1000 newborn-days]. Of the 83 ESBL-PE isolates identified, Escherichia coli was the most frequent species (n = 28, 34.1%), followed by Klebsiella pneumoniae (n = 20, 24.4%). Cox multivariate analysis showed that independent risk factors for ESBL-PE acquisition were low birth weight (adjusted Hazard-ratio (aHR) = 2.7, 95% CI [1.2; 5.9]), cesarean-section, (aHR = 3.4, 95% CI [1.7; 7.1]) and maternal use of antibiotics at delivery (aHR = 2.2, 95% CI [1.1; 4.5]). Our results confirm that mothers play a significant role in the neonatal acquisition of ESBL-PE. In LMICs, public health interventions during pregnancy should be reinforced to avoid unnecessary caesarean section, unnecessary antibiotic use at delivery and low birth weight newborns.

Early-Life Host-Microbiome Interphase: The Key Frontier for Immune Development

Human existence can be viewed as an "animal in a microbial world." A healthy interaction of the human host with the microbes in and around us heavily relies on a well-functioning immune system. As development of both the microbiota and the host immune system undergo rapid changes in early life, it is not surprising that even minor alterations during this co-development can have profound consequences. Scrutiny of existing data regarding pre-, peri-, as well as early postnatal modulators of newborn microbiota indeed suggest strong associations with several immune-mediated diseases with onset far beyond the newborn period. We here summarize these data and extract overarching themes. This same effort in turn sets the stage to guide effective countermeasures, such as probiotic administration. The objective of our review is to highlight the interaction of host immune ontogeny with the developing microbiome in early life as a critical window of susceptibility for lifelong disease, as well as to identify the enormous potential to protect and promote lifelong health by specifically targeting this window of opportunity.

Early life antibiotic exposure affects pancreatic islet development and metabolic regulation

Childhood antibiotic exposure has been recently linked with increased risk of metabolic disease later in life. A better understanding of this association would potentially provide strategies to reduce the childhood chronic disease epidemic. Therefore, we explored the underlying mechanisms using a swine model that better mimics human infants than rodents, and demonstrated that early life antibiotic exposure affects glucose metabolism 5 weeks after antibiotic withdrawal, which was associated with changes in pancreatic development. Antibiotics exerted a transient impact on postnatal gut microbiota colonization and microbial metabolite production, yet changes in the expression of key genes involved in short-chain fatty acid signaling and pancreatic development were detected in later life. These findings suggest a programming effect of early life antibiotic exposure that merits further investigation.

Prenatal and early-life predictors of atopy and allergic disease in Canadian children: results of the Family Atherosclerosis Monitoring In earLY life (FAMILY) Study

Prenatal and early-life environmental exposures play a key role in the development of atopy and allergic disease. The Family Atherosclerosis Monitoring In earLY life Study is a general, population-based Canadian birth cohort that prospectively evaluated prenatal and early-life traits and their association with atopy and/or allergic disease. The study population included 901 babies, 857 mothers and 530 fathers. Prenatal and postnatal risk factors were evaluated through questionnaires collected during the antenatal period and at 1 year. The end points of atopy and allergic diseases in infants were evaluated through questionnaires and skin prick testing. Key outcomes included atopy (24.5%), food allergy (17.5%), cow’s milk allergy (4.8%), wheezing (18.6%) and eczema (16%). The association between infant antibiotic exposure [odds ratio (OR): 2.04, 95% confidence interval (CI): 1.45–2.88] and increased atopy was noted in the multivariate analysis, whereas prenatal maternal exposure to dogs (OR: 0.60, 95% CI: 0.42–0.84) and acetaminophen (OR: 0.68, 95% CI: 0.51–0.92) was associated with decreased atopy. This population-based birth cohort in Canada demonstrated high rates of atopy, food allergy, wheezing and eczema. Several previously reported and some novel prenatal and postnatal exposures were associated with atopy and allergic diseases at 1 year of age.

High fecal IgA is associated with reduced Clostridium difficile colonization in infants

Colonization of infants with Clostridium difficile is on the rise. Although better tolerated by infants than adults, it is a risk factor for future allergic disease. The present study describes associations between infant fecal immunoglobulin A (IgA) and colonization with C. difficile in 47 infants enrolled in the Canadian Healthy Infant Longitudinal Development (CHILD) study. C. difficile colonization was observed in over half (53%) of the infants. Median IgA was lower in infants colonized with C. difficile (10.9 μg versus 25.5 μg per g protein; p = 0.18). A smaller proportion of infants with IgA in the highest tertile were colonized with C. difficile compared to the other tertiles (31.3% versus 64.5%, p = 0.03). In unadjusted analysis, odds of colonization with C. difficile was reduced by 75% (OR 0.25 95% CI 0.07, 0.91 p = 0.04) among infants with IgA in the highest tertile compared to those in the other tertiles. Following adjustment for parity, birth mode and breastfeeding, this association was even stronger (aOR 0.17, 95% CI 0.03, 0.94, p = 0.04). Our study provides evidence that high fecal IgA, independent of breastfeeding, is associated with reduced likelihood of C. difficile colonization in infancy.

Antibiotics, obesity and the link to microbes - what are we doing to our children?

BACKGROUND

Childhood obesity and overweight are among the greatest health challenges in the pediatric population. Obese individuals exhibit marked differences in the composition of the intestinal microbial community as compared to lean subjects. These changes in the gut microbiota precede the clinical manifestation of overweight. Convincing experimental data suggest a causal role for intestinal microbes in the development of obesity and associated metabolic disorders.

DISCUSSION

Exposure to antibiotics exerts a devastating impact on the intestinal microbial community. Epidemiological studies have provided evidence indicating that early or repeated childhood exposure to antibiotics is associated with increased risk of overweight later in childhood but the causal role of this exposure in obesity development is not clear. However, data from studies conducted using experimental animal models indicate that antibiotic-induced changes in the gut microbiota influence host metabolism and lead to fat accumulation. The intestinal microbiota perturbation caused by antibiotic exposure in the perinatal period appears to program the host to an obesity-prone metabolic phenotype, which persists after the antibiotics have been discontinued and the gut microbiota has recovered. These observations may have serious implications in the clinical setting, since a substantial number of human infants are subjected to antibiotic treatment through the mother during delivery or directly in the immediate neonatal period. The clinical significance of these exposures remains unknown. Prudent use of antibiotics is paramount not only to reduce the propagation of antibiotic-resistant organisms but also to minimize the potentially detrimental long-term metabolic consequences of early antibiotic exposure. Improved means of reliably detecting neonates with bacterial infection would reduce the need for empirical antibiotic exposure initiated based on nonspecific symptoms and signs or risk factors. Finally, means to support healthy microbial contact in neonates and infants requiring antibiotic treatment are needed.

Assessing Early Life Factors for Eosinophilic Esophagitis: Lessons From Other Allergic Diseases

OPINION STATEMENT

Few studies have been conducted to investigate possible early life determinants for eosinophilic esophagitis. An improved understanding of the etiologic factors implicated in disease development would further elucidate possible disease pathogenesis, inform therapeutic targets for disease treatment, and identify possible modifiable factors for disease prevention in genetically susceptible individuals. Although eosinophilic esophagitis is increasing in incidence and prevalence, the disease remains relatively rare, posing challenges for studying etiologic factors in disease development. Eosinophilic esophagitis is believed to be antigen-mediated, and most patients with EoE have concomitant atopic disease. In recent years, the evolution of our understanding of possible etiologic mechanisms in allergic disease has been informed by our understanding of how early life perturbations can lead to dysbiosis in the colonization of the microflora in the gastrointestinal tract and subsequent dysregulated immune development. Perturbations include factors such as antibiotic use, including prenatal, intra-antepartum, and infancy use of antibiotics, Cesarean delivery, preterm delivery, and neonatal intensive care admission. This article provides a review of these recent developments, as they relate to atopic disease, to inform future directions in the study of early life etiologic factors in the development of eosinophilic esophagitis.

Antepartum Antibiotic Treatment Increases Offspring Susceptibility to Experimental Colitis: A Role of the Gut Microbiota

Background and aims

Postnatal maturation of the immune system is largely driven by exposure to microbes, and thus the nature of intestinal colonization may be associated with development of childhood diseases that may persist into adulthood. We investigated whether antepartum antibiotic (ATB) therapy can increase offspring susceptibility to experimental colitis through alteration of the gut microbiota.

Methods

Pregnant C57Bl/6 mice were treated with cefazolin at 160 mg/kg body weight or with saline starting six days before due date. At 7 weeks, fecal samples were collected from male offspring after which they received 4% dextran sulfate sodium (DSS) in drinking water for 5 days. Disease activity index, histology, colonic IL-6, IL-1β and serum C-reactive protein (CRP) were determined. The V3-V4 region of colonic and fecal bacterial 16S rRNA was sequenced. Alpha-, beta-diversity and differences at the phylum and genus levels were determined, while functional pathways of classified bacteria were predicted.

Results

ATB influenced fecal bacterial composition and hence bacterial functional pathways before induction of colitis. After induction of colitis, ATB increased onset of clinical disease, histologic score, and colonic IL-6. In addition, ATB decreased fecal microbial richness, changed fecal and colon microbial composition, which was accompanied by a modification of microbial functional pathways. Also, several taxa were associated with ATB at lower taxonomical levels.

Conclusions

The results support the hypothesis that antepartum antibiotics modulate offspring intestinal bacterial colonization and increase susceptibility to develop colonic inflammation in a murine model of colitis, and may guide future interventions to restore physiologic intestinal colonization in offspring born by antibiotic-exposed mothers.

Impact of maternal intrapartum antibiotics, method of birth and breastfeeding on gut microbiota during the first year of life: a prospective cohort study

OBJECTIVE

Dysbiosis of the infant gut microbiota may have long-term health consequences. This study aimed to determine the impact of maternal intrapartum antibiotic prophylaxis (IAP) on infant gut microbiota, and to explore whether breastfeeding modifies these effects.

DESIGN

Prospective pregnancy cohort of Canadian infants born in 2010-2012: the Canadian Healthy Infant Longitudinal Development (CHILD) Study.

SETTING

General community.

SAMPLE

Representative sub-sample of 198 healthy term infants from the CHILD Study.

METHODS

Maternal IAP exposures and birth method were documented from hospital records and breastfeeding was reported by mothers. Infant gut microbiota was characterised by Illumina 16S rRNA sequencing of faecal samples at 3 and 12 months.

MAIN OUTCOME MEASURES

Infant gut microbiota profiles.

RESULTS

In this cohort, 21% of mothers received IAP for Group B Streptococcus prophylaxis or pre-labour rupture of membranes; another 23% received IAP for elective or emergency caesarean section (CS). Infant gut microbiota community structures at 3 months differed significantly with all IAP exposures, and differences persisted to 12 months for infants delivered by emergency CS. Taxon-specific composition also differed, with the genera Bacteroides and Parabacteroides under-represented, and Enterococcus and Clostridium over-represented at 3 months following maternal IAP. Microbiota differences were especially evident following IAP with emergency CS, with some changes (increased Clostridiales and decreased Bacteroidaceae) persisting to 12 months, particularly among non-breastfed infants.

CONCLUSIONS

Intrapartum antibiotics in caesarean and vaginal delivery are associated with infant gut microbiota dysbiosis, and breastfeeding modifies some of these effects. Further research is warranted to explore the health consequences of these associations.

TWEETABLE ABSTRACT

Maternal #antibiotics during childbirth alter the infant gut #microbiome.

Prenatal exposure to systemic antibacterials and overweight and obesity in Danish schoolchildren: a prevalence study

BACKGROUND/OBJECTIVE

Prenatal exposure to antibacterials may permanently dysregulate fetal metabolic patterns via epigenetic pathways or by altering maternal microbiota. We examined the association of prenatal exposure to systemic antibacterials with overweight and obesity in schoolchildren.

SUBJECTS/METHODS

We conducted a prevalence study among Danish schoolchildren aged 7-16 years using data from routine school anthropometric evaluations conducted during 2002-2013. Prenatal exposure to antibacterials was ascertained by using maternal prescription dispensations and infection-related hospital admissions during pregnancy. We defined overweight and obesity among the children using standard age- and sex-specific cutoffs. We computed sex-specific adjusted prevalence ratios (aPRs) of overweight and obesity associated with exposure to prenatal antibacterials, adjusting for maternal age at delivery, marital status, smoking in pregnancy and multiple gestation; we also stratified the analyses by birth weight.

RESULTS

Among 9886 schoolchildren, 3280 (33%) had prenatal exposure to antibacterials. aPRs associated with the exposure were 1.26 (95% confidence interval (CI): 1.10-1.45) for overweight and 1.29 (95% CI: 1.03-1.62) for obesity. Among girls, aPRs were 1.16 (95% CI: 0.95-1.42) for overweight and 1.27 (95% CI: 0.89 to 1.82) for obesity. Among boys, aPRs were 1.37 (95% CI: 1.13-1.66) for overweight and 1.29 (95% CI: 0.96-1.73) for obesity. The aPR for overweight was higher among schoolchildren with birth weight <3500 g (aPR: 1.30, 95% CI: 1.05-1.61) than in schoolchildren with birth weight ⩾3500 g (aPR: 1.18, 95% CI: 0.95-1.46). Inversely, the association for obesity was higher among schoolchildren with birth weight ⩾3500 g (aPR: 1.35, 95% CI: 1.00-1.81) than among those who were <3500 g at birth (aPR: 1.16, 95% CI: 0.82-1.65).

CONCLUSIONS

Prenatal exposure to systemic antibacterials is associated with an increased risk of overweight and obesity at school age, and this association varies by birth weight.

Natural environments, ancestral diets, and microbial ecology: is there a modern "paleo-deficit disorder"? Part II

Famed microbiologist René J. Dubos (1901–1982) was an early pioneer in the developmental origins of health and disease (DOHaD) construct. In the 1960s, he conducted groundbreaking research concerning the ways in which early-life experience with nutrition, microbiota, stress, and other environmental variables could influence later-life health outcomes. He recognized the co-evolutionary relationship between microbiota and the human host. Almost 2 decades before the hygiene hypothesis, he suggested that children in developed nations were becoming too sanitized (vs. our ancestral past) and that scientists should determine whether the childhood environment should be “dirtied up in a controlled manner.” He also argued that oft-celebrated growth chart increases via changes in the global food supply and dietary patterns should not be equated to quality of life and mental health. Here in the second part of our review, we reflect the words of Dubos off contemporary research findings in the areas of diet, the gut-brain-axis (microbiota and anxiety and depression) and microbial ecology. Finally, we argue, as Dubos did 40 years ago, that researchers should more closely examine the relevancy of silo-sequestered, reductionist findings in the larger picture of human quality of life. In the context of global climate change and the epidemiological transition, an allergy epidemic and psychosocial stress, our review suggests that discussions of natural environments, urbanization, biodiversity, microbiota, nutrition, and mental health, are often one in the same.