Development of the early-life gut microbiome and associations with eczema in a prospective Chinese cohort

IMPORTANCE

Eczema is a major allergic disease in children, which is particularly prevalent in Chinese children during their first year of life. In this study, we showed that alterations in the infant gut microbiota precede the development of eczema in a prospective Chinese cohort. In particular, we discovered enrichments of the genera Clostridium sensu stricto 1 and Finegoldia in the cases at 3 and 1 month of age, respectively, which may represent potential targets for intervention to prevent eczema. Besides, we identified a depletion of Bacteroides from 1 to 6 months of age and an enrichment of Clostridium sensu stricto 1 at 3 months in the eczema cases, patterns also observed in C-section-born infants within the same time frames, providing first evidence to support a role of the gut microbiota in previously reported associations between C-section and increased risk of eczema in infancy.

Delivery Mode and Perinatal Antibiotics Influence the Infant Gut Bacteriome and Mycobiome: A Network Analysis

Both exposure to antibiotics at birth and delivery via Caesarean section influence the gut bacteriome's development in infants. Using 16S rRNA and internal transcribed spacer sequencing on the Ion Torrent platform, we employed network analysis to investigate the bacterial and fungal interkingdom relationships in the gut microbiome from birth to age 18 months in a prospective cohort study of 140 infants. The gut microbiome at ages six and 18 months revealed distinctive microbial interactions, including both positive and negative associations between bacterial and fungal genera in the gut ecosystem. Perinatal factors, delivery mode and intrapartum antibiotic exposure affected the associations between bacterial and fungal species. In infants exposed and unexposed to perinatal antibiotics, the gut microbiome formed distinct networks for the bacteriome and mycobiome. The fungi Saccharomyces, Trichosporon, Pezoloma, Cystofilobasidium, Rigidoporus and Fomitopsis were strongly associated with exposure to antibiotics at birth. Hyaloscypha, Trichosporon, Fomitopsis and Vishniacozyma were strongly associated with the control group that was not exposed to antibiotics. Five distinct networks were formed according to delivery mode. The present study confirms that bacteria and fungi clearly interact in the infant gut ecosystem. Furthermore, perinatal factors appear to influence the relationships between bacteria and fungi in the developing gut microbiome.

Group B Streptococcus and the risk of perinatal morbidity and mortality following term labor

Streptococcus agalactiae (group B Streptococcus) colonizes the genital tract of approximately 20% of pregnant women. In the absence of intervention, approximately 1% of infants born to colonized mothers exhibit a clinical infection. This has led to implementation of screening and intervention in the form of intrapartum antibiotic prophylaxis in many countries, including the United States. However, screening has not been introduced in a substantial minority of other countries because of the absence of supportive level 1 evidence, the very large number needed to treat to prevent 1 case, and concerns about antimicrobial resistance. Optimal screening would involve rapid turnaround (to facilitate intrapartum testing) and report antibiotic sensitivity, but no such method exists. There is significant scope for a personalized medicine approach, targeting intrapartum antibiotic prophylaxis to cases at greatest risk, but the pathogen and host factors determining the risk of invasive disease are incompletely understood. Epidemiologic data have indicated the potential of prelabor invasion of the uterus by group B Streptococcus, and metagenomic analysis revealed the presence of group B Streptococcus in the placenta in approximately 5% of pregnant women at term before onset of labor and membrane rupture. However, the determinants and consequences of prelabor invasion of the uterus by group B Streptococcus remain to be established. The vast majority (98%) of invasive neonatal disease is caused by 6 serotypes, and hexavalent vaccines against these serotypes have completed phase 2 trials. However, an obstacle to phase 3 studies is conducting an adequately powered trial to demonstrate clinical effectiveness given that early-onset disease affects approximately 1 in 1000 births in the absence of vaccination.

Evaluation of a clinical protocol for the management of fever in labor among pregnant women at term: A quality-improvement study

OBJECTIVE

To assess the impact of a quality-improvement initiative designed to increase diagnostic accuracy and adequate management of clinical chorioamnionitis (CC) at a tertiary center. Chorioamnionitis occurs in 1%-13% of term pregnancies and increases maternal and neonatal peripartum complications; often over-diagnosed, it leads to unnecessary investigations and treatments.

METHODS

This was an interrupted time-series study. In September 2017 two interventions were implemented: (1) staff training and (2) standardized clinical protocol for the management of fever in labor. All singleton term pregnancies were included. CC cases were reviewed in the pre-intervention (2015-2016, n = 179) and post-intervention (2017-2018, n = 142) groups. CC criteria based on the American College of Obstetricians and Gynecologists guidelines, antibiotics, maternal and neonatal outcomes, and pathology were compared. A cost-consequence analysis was performed.

RESULTS

Incidence of CC decreased from 8.2 to 5.6 per 10 person-year (P < 0.001). This was associated with a significant increase in diagnostic accuracy from 15.7% to 73.2% (P < 0.001). Weight-adjusted tobramycin dosage improved from 8.8% to 69.1% (P < 0.001). Maternal length of hospitalization and readmissions decreased significantly, without affecting neonatal sepsis rate. Interventions decreased yearly hospital costs associated with CC by 23.4%.

CONCLUSION

Standardizing the management of fever in labor significantly increased the diagnostic accuracy of CC and decreased the misuse of antibiotics in term pregnancies. CC costs decreased by 23.4%.

Intrapartum antibiotics and childhood asthma and allergic rhinitis: a retrospective cohort study

OBJECTIVE

This study aimed to evaluate the association between intrapartum antibiotics (IABX) and asthma and allergic rhinitis among children by ages 6, 8 and 10 years.

DESIGN

Retrospective cohort.

SETTING AND POPULATION

Data were collected though Kaiser Permanente Northern California's (KPNC) integrated healthcare system. Children were eligible if they were born in a KPNC hospital between 1997 and 2012 and stayed enrolled through age 6.

METHODS

Modified Poisson regressions with robust error variances were used to estimate risk ratios for IABX and each outcome at each follow-up age during two separate time periods: 1997-2004 (n = 91 739) and 2005-2012 (n = 108 314).

MAIN OUTCOME MEASURES

Asthma and allergic rhinitis by ages 6, 8 and 10.

RESULTS

The proportion of women receiving IABX increased drastically over the study period (from 4% in 1997 to 49% in 2011), while the incidence of asthma (8%) and allergic rhinitis (6%) stayed relatively stable. In adjusted models, risk ratios for the association between IABX and asthma and allergic rhinitis were largely compatible with the null, with some slightly elevated risk ratios observed. For births from 1997 to 2004, risk ratios for asthma were 1.08 (95% CI 1.00-1.17) at age 6, 1.05 (95% CI 0.97-1.15) at age 8, and 1.08 (95% CI 0.99-1.18) at age 10. For births from 2005 to 2012, risk ratios were 1.00 (95% CI 0.95-1.04) at age 6, 1.07 (95% CI 1.01-1.12) at age 8, and 1.11 (95% CI 1.03-1.20) at age 10.

CONCLUSIONS

Exposure to intrapartum antibiotics is not a strong predictor of childhood asthma or allergic rhinitis risk.

TWEETABLE ABSTRACT

Exposure to intrapartum antibiotics is not a strong predictor of childhood asthma or allergic rhinitis risk.

Association of Intrapartum Risk Factors and Infant Clinical Indicators with Culture Confirmed Early Onset Neonatal Sepsis in a Secondary Care Rural Hospital in India

OBJECTIVE

The aim of this study is to determine the association of intrapartum risk factors and infant clinical indicators using the National Institute for Health and Care Excellence (NICE) criteria with culture-positive early-onset neonatal sepsis (EONS) from a rural secondary healthcare facility where intrapartum prophylactic antibiotics are routinely administered to high-risk mothers.

METHODS

A single-center prospective observational study was conducted between July 2017 and September 2018. All intramural neonates with at least one NICE criteria at less than 72 h of life, were included. Univariate logistic regression and multivariable logistic backward elimination analyses were conducted to investigate individual risk factors and predictive models for culture proven EONS.

RESULTS

Of 236 newborns who were at risk for EONS by NICE criteria, 32 (13.8%) had positive blood cultures. Klebsiella species (n = 13, 39.4%) and Acinetobacter species (n = 11, 33.3%) were the most common isolated bacteria. In univariate analysis, the number of infant clinical indicators were associated with culture positive EONS (OR 1.36; 95% CI 1.01-1.81), but not the number of intrapartum risk factors (OR 0.76; 95% CI 0.4-1.29). The multivariate logistic regression with backward elimination procedure suggested that a model including absolute neutrophil count [adjusted OR (aOR) 0.81; 95% CI 0.72-0.92], C-reactive protein (aOR 1.24; 95% CI 1.08-1.43) and the number of clinical indicators (aOR 1.29; 95% CI 0.93-1.80) could be useful to predict culture positive EONS in our setting.

CONCLUSION

In this maternal and neonatal cohort, infant clinical indicators rather than intrapartum risk factors were associated with culture confirmed EONS.

Impact of Intrapartum Antibiotic Prophylaxis on Offspring Microbiota

Infants are born into a world filled with microbes and must adapt without undue immune response while exploiting the microbiota's ability to produce otherwise unavailable nutrients. The process by which humans and microbes establish this relationship has only recently begun to be studied with the aid of genomic methods. Nearly half of all pregnant women receive antibiotics during gestation to prevent maternal and neonatal infection. Though this has been largely successful in reducing early-onset sepsis, we have yet to understand the long-term consequences of antibiotic administration during gestation to developing infants. Studies involving antibiotic use in infants suggest that dysbiosis during this period is associated with increased obesity, allergy, autoimmunity, and chronic diseases in adulthood, however, research around the limited doses of intravenous antibiotics used for intrapartum prophylaxis is limited. In this mini review, we focused on the state of the science regarding the effects of intrapartum antibiotic prophylaxis on the newborn microbial colonization process. Although, the literature indicates that there is wide variety in the specific bacteria that colonize infants from birth, limited parenteral antibiotic administration prior to delivery consistently affects the microbiota of infants by decreasing bacteria in the phylum Bacteroidetes and increasing bacteria in the phylum Proteobacteria, thus altering the normal pattern of colonization that infants experience. Delivery by cesarean section and formula feeding magnify and prolong this effect. Our mini review shows that the impact of intravenous antibiotic administration during gestation has on early colonization, growth, or immune programming in the developing offspring has not been well studied in human or animal models.

Meta-analysis on prevalence of vaginal group B streptococcus colonization and preterm births in India

OBJECTIVE

Preterm birth is a major cause of neonatal morbidity and mortality. Vaginal colonization of Group B Streptococci (GBS) is associated with increased risk of preterm birth. However, the association of GBS colonization and preterm births in the Indian context remains an unrecognized problem.

DATA SOURCES

Data was collected using various online search tools from 36 (1981-2019) Indian studies comprising 9778 cases.

METHOD OF STUDY SELECTION

Studies reporting the prevalence of GBS colonization in the Indian population were included.

TABULATION, INTEGRATION, AND RESULTS

The prevalence of GBS colonization in pregnant Indian women was estimated to be 7.8% (763/9778) with wide heterogeneity across studies. The prevalence of GBS was 7.4% when culture methods were used and 11.6% with use of immunological methods. The detection rate of GBS almost doubled when enrichment was used in the culture method (8.1 vs. 5%). The risk of preterm delivery was higher (OR 7.9) among women with GBS colonization as compared to those without GBS.

CONCLUSIONS

As compared to the western population, there is low prevalence of GBS colonization among Indian pregnant women; however, the risk of preterm births with GBS colonization is higher. There is a need to implement a universal GBS screening program prior to intrapartum antibiotic prophylaxis in women experiencing preterm births.

Risk Factors for Postpartum Maternal Infection Following Spontaneous Vaginal Delivery Complicated by Chorioamnionitis

Objective  Guidelines for the management of chorioamnionitis include intrapartum antibiotics, while postpartum antibiotics after spontaneous vaginal delivery (SVD) are reserved high-risk women. Our objective is to describe the incidence of and risk factors for postpartum infection after SVD complicated by chorioamnionitis. Study Design  This is a retrospective study of SVDs with clinically diagnosed chorioamnionitis at a single center. The primary outcome was a composite of postpartum infection. Women who developed the primary outcome were compared with those who did not using bivariate statistics. Regression models were developed to estimate adjusted odds of outcomes. Results  In this cohort, 346 women underwent SVD complicated by chorioamnionitis. Of these, 23 (6.6%) developed postpartum infections (endometritis n  = 7, urinary tract infection/pyelonephritis n  = 6, sepsis n  = 4, and perineal wound infection n  = 6). Receipt of antibiotics intra- or postpartum did not differ between groups, but women with postpartum infections were more likely to deliver prior to 32 weeks (17.4 vs. 4.9%, p  = 0.04). When controlling for antibiotic use, delivery at < 32 weeks was associated with 3.8-fold increased (95% confidence interval: 1.07-13.7) odds of postpartum infection. Conclusion  Postpartum infections occur in ∼1/15 women delivering vaginally with chorioamnionitis, with those who deliver at < 32 weeks' gestation being at increased risk.

Should clinical suspicion shift to ampicillin resistance organisms in certain preterm premature rupture of membranes scenarios?: Case of early-onset sepsis caused by E coli

This case highlights the importance antibiotic stewardship, including reexamining current regimens use for intrapartum antibiotic prophylaxis, which may be accountable for the shift in organism responsible for some cases of early-onset sepsis.

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.

Intrapartum antibiotics for prolonged rupture of membranes at term to prevent Group B Streptococcal sepsis

The timely administration of intrapartum antibiotic prophylaxis (IAP) to eligible pregnant mothers reduces the risk of early onset Group B Streptococcus (GBS) neonatal sepsis. The incidence of neonatal GBS sepsis is increasing, in spite of national guidelines for its prevention. This retrospective cohort study was undertaken to assess the incidence of culture-proven GBS sepsis before and after a change of practice on intrapartum management of GBS sepsis in babies born at Sunderland Royal Hospital between January 1 2008 and December 31 2017. The data regarding the risk factors, the intrapartum antibiotic prophylaxis and the outcomes of the babies were collected. Twenty-nine cases were identified and presented in two epochs-before and after changing guidelines for intrapartum management. There was a statistically significant reduction in early onset sepsis rates and no difference in late-onset sepsis rates. The prolonged rupture of membranes is a significant risk factor at any gestation. Impact statement What is already known on this subject? Appropriate intrapartum administration of antibiotics in mothers reduces 80% of early-onset GBS infections. In the United Kingdom, IAP is given based on risk factors, which fail to accurately identify and treat the woman who harbours GBS in the birth canal in labour and the incidence of GBS neonatal sepsis is increasing. The national guideline on the prevention of GBS sepsis is not consistent and is open to interpretation. What do the results of this study add? This study highlights prolonged rupture of membranes as a significant risk factor at any gestation and there were missed opportunities to prevent GBS sepsis in term babies with the prolonged rupture of membranes. This study also highlights that it is possible to reduce the neonatal GBS sepsis burden by adhering to guidelines and administering timely intrapartum antibiotics. What are the implications of these findings for clinical practice and/or further research? The timely administration of IAP to all eligible women is possible if the national guidelines are consistent and interpreted correctly. Our national guideline on the prolonged rupture of membranes at term is not clear and is interpreted differently. If IAP is provided in all those with risk factors irrespective of gestation, this would involve additional costs to the NHS; but in the long term, it will benefit as it reduces morbidity.

Breast Milk Microbiota Is Shaped by Mode of Delivery and Intrapartum Antibiotic Exposure

The mode of delivery has been suggested to modulate the bacterial composition of breast milk but the impact of intrapartum antibiotic use on the milk microbiota is currently not known. The aim of this study was to analyze the effects of the mode of the delivery and intrapartum antibiotic administration on the microbial composition of breast milk. Breast milk samples were collected from 84 healthy mothers 1 month after the delivery. In total, 61 mothers had delivered vaginally, 23 of which had received intrapartum antibiotics, 13 women had delivered with non-elective cesarean section, 7 of which had received antibiotics, and 10 mothers had delivered with elective cesarean section without intrapartum antibiotic treatment. Both mode of delivery and intrapartum antibiotic exposure were significantly associated with changes in the milk microbial composition as assessed by analysis of similarities (ANOSIM) test (p = 0.001). The mode of delivery had a more profound effect on the milk microbiota composition as compared to intrapartum antibiotic exposure. Although the clinical significance of breast milk microbiota is currently poorly understood, this study shows that cesarean section delivery has an independent effect on breast milk microbiota composition. The dysbiosis observed in infants born by cesarean section delivery may be aggravated by the aberrant breast milk microbiota.

Incidence of fever in labor and risk of neonatal sepsis

BACKGROUND

The current recommendation regarding the management of a term newborn delivered of a mother with an intrapartum fever or a diagnosis of clinical chorioamnionitis is that the neonate should have baseline laboratory work drawn along with blood cultures and be universally treated with antibiotics until culture results return. These guidelines report that the rate of intrapartum fever is about 3%; however, a few large studies suggest that the rate is higher at about 7%.

OBJECTIVE

We sought to prospectively evaluate the rate of fever during labor in a large number of deliveries and determine the rate of early-onset neonatal sepsis in newborns delivered from mothers with an intrapartum fever compared with newborns delivered from mothers without intrapartum fever.

STUDY DESIGN

This was a prospective cohort study of all temperatures obtained in women in labor from Jan. 1, 2011, through June 30, 2014. Every patient with a fever of ≥38°C at ≥36 weeks' gestation was evaluated for gestational age, parity, spontaneous or induced labor, group B streptococcus status, regional anesthesia, mode of delivery, treatment with intrapartum antibiotics, and whether a clinical diagnosis of chorioamnionitis was made by the managing physician. Neonates were assessed for blood culture results, neonatal intensive care unit admission, length of stay, and any major newborn complications. Statistical analysis involved χ², Fisher exact, and Student t test.

RESULTS

A total of 412 patients (6.8%; 95% confidence interval, 6.2-7.5%) developed a fever in 6057 deliveries at ≥36 weeks' gestation. No cases of maternal sepsis occurred. Of the 417 newborns (5 sets of twins), only 1 (0.24%; 95% confidence interval, 0.01-1.3%) developed early-onset neonatal sepsis with a positive blood culture for Escherichia coli. There were 4 cases (0.07%; 95% confidence interval, 0.02-0.18%) of early-onset neonatal sepsis in the 5697 newborns (52 sets of twins) delivered from mothers who were not febrile and this difference was not significant (P = .3). The positive blood cultures in these 4 neonates were 3 group B streptococcus and 1 Enterococcus. The overall rate of early-onset neonatal sepsis in this population of newborns delivered at ≥36 weeks' gestation was 0.82/1000 deliveries.

CONCLUSION

The incidence of an intrapartum fever of ≥38°C in pregnancies at ≥36 weeks' gestation is common at 6.8% and this is consistent with the findings of a few other large retrospective studies. The rate of an intrapartum fever occurs in approximately 1 in 15 women in labor. The risk of neonatal sepsis in newborns delivered of mothers with intrapartum fever or a diagnosis of clinical chorioamnionitis is low at 0.24%, a rate that is <1 in 400. The recommendation for universal laboratory work, cultures, and antibiotic treatment pending culture results for this newborn population needs further examination.

Antibiotic Therapy for Chorioamnionitis to Reduce the Global Burden of Associated Disease

Chorioamnionitis is associated with significant maternal and neonatal morbidity and mortality throughout the world. In developed countries, great progress has been made to minimize the impact of chorioamnionitis, through timely diagnosis and appropriate treatment. In the global setting, where many women deliver outside the healthcare facilities, this diagnosis is frequently overlooked and not properly treated. In addition to its impact on maternal health, a significant proportion of neonatal morbidity and mortality can be prevented by both recognition and access to readily available treatment. With the increasing focus on saving the most vulnerable members of society, we echo the need for providing parturient women with suspected chorioamnionitis universal access to appropriate therapy. We describe known effective antibiotic therapies for chorioamnionitis and provide an overview of additional potential antimicrobial treatments that might be effectively implemented in areas with limited access to care.

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.