Chorioamnionitis: time for a new approach

Possible Rates of Detection of Neonatal Sepsis Pathogens in the Context of Microbiological Diagnostics in Mothers - Real World Data

Objective

The aim of this study was to identify the rate of detection of neonatal sepsis pathogens in maternal microbiological smears.

Study Design

This is a retrospective study conducted at a Level 1 perinatal center in the context of routine care from 2014 to 2019. For all premature infants and neonates with neonatal sepsis, the neonatal and maternal microbiological findings were examined to see if there was a match.

Results

During the study period, a total of 948 premature or newborn infants were identified as having a neonatal infection. Among all of the premature or newborn infants, 209 (22%) met the diagnostic criteria for neonatal sepsis; of these, 157 were premature births and 52 were full-term births. We evaluated the microbiological findings for these 209 mother and child pairs. No pathogens were detected in 27 out of 157 mothers of premature infants (17.1%) and in 31 out of 52 mothers of full-term infants (59.6%). In the premature infant group there were pairs with matching pathogens in 30 out of 130 cases (23.1%, 95% CI: 16.1-31.3), and in the full-term infant group there was a match in 4 out of 21 cases (19%, 95% CI: 5.4-41.9). The number needed to test to have a 90% probability of success for pathogen detection varies between 9 and 11 in the most favorable case and 26 and 32 in the least favorable case, depending on the evaluation method.

Conclusion

In cases of neonatal sepsis, the sepsis-causing pathogen was successfully detected through prior analysis of a maternal smear in 7% of full-term infants and in 19% of premature infants. The number needed to test was relatively high in all groups. The value of maternal smears for identifying neonatal sepsis-causing pathogens needs to be critically questioned.

Initiative to Reduce Antibiotic Exposure of Asymptomatic Infants Born to Mothers with Intraamniotic Infection

Infants born to mothers with intraamniotic infection (IAI) received antibiotic treatment per the Centers for Disease Control and Prevention and American Academy of Pediatrics guidelines in our neonatal intensive care unit (NICU) for early-onset bacterial sepsis evaluation. We conducted a quality improvement project to decrease antibiotic use and NICU admission in infants born to mothers with IAI.

Evaluating definitions for maternal fever as diagnostic criteria for intraamniotic infection in low-risk pregnancies

BACKGROUND

Conflicting statements by stakeholders in obstetric care have suggested different criteria for defining peripartum fever and suspected intraamniotic infection, which have not been evaluated.

METHODS

A case-control study of pregnancies between 35 and 41 weeks at a single tertiary care center between January 2016 and December 2017. Cases with pathology-confirmed chorioamnionitis were identified, and demographic data, risk factors, and neonatal outcomes were extracted from the medical record. The American College of Gynecology (ACOG) and National Institutes of Health (NIH) Workshop guidelines for identifying isolated maternal fever and suspected intraamniotic infection were applied, retrospectively. Odds ratios, sensitivity/specificity, and predictive value of each guideline for pathology-confirmed chorioamnionitis and for secondary outcomes of interest were determined.

RESULTS

943 mother-infant dyads were evaluated including 41 (4.3%) with pathology-confirmed chorioamnionitis. Among cases, 18 (43.9%) experienced any maternal temperature ≥38°C (100.4°F) with 12 (29.2%) and 8 (19.5%) cases meeting criteria for isolated maternal fever according to the ACOG and Workshop guidelines, respectively. Furthermore, the ACOG and Workshop guidelines correctly identified 6 (14.6%) and 3 (7.3%) of cases of pathology-confirmed chorioamnionitis with high agreement between definitions (κ = 0.63). Laboratory evaluation, antimicrobial exposure, and prolonged length of stay in offspring are substantially higher in cases as compared to controls.

CONCLUSIONS

Guidelines that rely on maternal fever definitions for the diagnosis of suspected intraamniotic infection exhibit high agreement with low sensitivity, but high specificity and negative predictive value for pathology-confirmed chorioamnionitis. Maternal temperature ≥38°C continues to drive clinical decision-making for both mother and offspring.

Chorioamnionitis in utero, schizophrenia in adulthood: limited current evidence-future research focus?

Background: Developmental adaptive processes during gestation that are known to be involved in permanent changes in physiology and metabolism or "early life programming" can adversely affect fetal brain development, impacting both brain structure and function.Data: Emerging evidence strongly supports the developmental origin of schizophrenia, which may potentially be a result of prenatal exposure to a diversity of factors, especially infections, in genetically predisposed subjects. Structural and functional brain changes during development of schizophrenia are determined by genetic components, altered expression of schizophrenia risk genes and epigenetic dysregulation. However, the precise mechanisms underlying these relationships remain unclear. Findings from human and animal studies suggest that inflammatory-immune responses and activation of oxidative stress pathways are crucial in mediating intrauterine infection-induced neurodevelopmental and neuropsychiatric diseases.Aim: Considering the high prevalence of intrauterine inflammation in the context of chorioamnionitis during human pregnancy and the paucity of knowledge on fetal programming of schizophrenia, this mini review aims to exclusively consolidate the current evidence supporting a potential association between chorioamnionitis and schizophrenia.

Gross appearance of the fetal membrane on the placental surface is associated with histological chorioamnionitis and neonatal respiratory disorders

An opaque fetal membrane based on gross appearance is traditionally indicative of histological chorioamnionitis; however, to the best of our knowledge, there is currently no supportive evidence, and its diagnostic efficiency has not yet been scientifically demonstrated. The present study aimed to provide scientific insights into the traditional concept of an opaque fetal membrane based on gross appearance being an indicator of histological chorioamnionitis. We examined the placental pathology after screening of the placental gross appearance and perinatal complications and did not examine uncomplicated deliveries. We investigated the relationship between the presence of an opaque fetal membrane and histological chorioamnionitis (Cohort 1, 571 placentas) or the outcomes of neonates delivered at term (Cohort 2, 409 placentas) at Hamamatsu University School of Medicine between 2010 and 2017. The judgment of a positive opaque fetal membrane based on gross appearance correlated with histological chorioamnionitis (Cohort 1). Its sensitivity and specificity were 66.7 and 89.9%, respectively, while positive and negative predictive values were 86.8 and 73.0%, respectively. The judgment of a positive opaque fetal membrane based on gross appearance significantly correlated with chorioamnionitis-related complications in term newborns after adjustments for confounding factors (OR;1.82 [1.07–3.11], P<0.05) (Cohort 2). A correlation was observed even after adjustments for confounding factors. The present study is the first to demonstrate that the judgment of a positive opaque fetal membrane based on gross appearance correlated with histological chorioamnionitis as well as chorioamnionitis-related complications in newborns delivered at term. The present results provide support for the traditionally-described importance of gross inspections for an opaque fetal membrane soon after birth.

Small RNA (sRNA) expression in the chorioallantois, endometrium and serum of mares following experimental induction of placentitis

Intrauterine infection and inflammation remain a major cause of preterm labour in women and mares, with little known about small RNA (sRNA) expression in tissue or circulation. To better characterise placental inflammation (placentitis), we examined sRNA expression in the endometrium, chorioallantois and serum of mares with and without placentitis. Disease was induced in 10 mares via intracervical inoculation of Streptococcus equi ssp. zooepidemicus, either with moderate or high levels of inoculum; three uninoculated gestationally matched mares were used as controls. Matched chorioallantois and endometrium were sampled in two locations: Region 1, gross inflammation near cervical star with placental separation and Region 2, gross inflammation without placental separation. In Region 1, 26 sRNAs were altered in chorioallantois, while 20 were altered in endometrium. Within Region 2, changes were more subdued in both chorioallantois (10 sRNAs) and endometrium (two sRNAs). Within serum, we identified nine significantly altered sRNAs. In summary, we have characterised the expression of sRNA in the chorioallantois, the endometrium and the serum of mares with experimentally induced placentitis using next-generation sequencing, identifying significant changes within each tissue examined. These data should provide valuable information about the physiology of placental inflammation to clinicians and researchers alike.

Questionnaire survey on the management of pregnant women with preterm premature rupture of membranes

Objective

The aim of this survey was to study the status of the actual practice in the management of preterm premature rupture of membranes (PPROM) between 34.0 and 36.6 weeks of gestation.

Methods

This survey was designed for obstetricians who work in secondary or tertiary medical institutions and attended the Korean Society of Maternal Fetal Medicine conference held on July 1, 2017, in Korea, using a structured questionnaire consisting of 5 questions.

Results

The most commonly used antibiotic was cephalosporin monotherapy (34.5%). Antenatal corticosteroids were applied up to 34.0 weeks of gestation in half of the respondents. The frequency of expectant management was higher than that of immediate delivery in women with PPROM between 34.0 and 36.6 weeks of gestation (57.4%). The most important factor in determining immediate delivery was the symptoms of chorioamnionitis.

Conclusion

The present survey showed a considerable variation in the actual management of PPROM in women, especially the optimal timing of delivery. More evidenced-based studies with statistical power are required to decrease the heterogeneity of clinical practice.

Intrapartum beta-lactam antibiotics for preventing group B streptococcal early-onset disease: can we abandon the concept of 'inadequate' intrapartum antibiotic prophylaxis?

Introduction: Neonatal sepsis remains a serious and potentially fatal illness. Intrapartum antibiotic prophylaxis (IAP) prevents group B streptococcal (GBS) early-onset sepsis. The optimal duration of IAP (adequate IAP) to reduce vertical transmission of GBS has been debated. Understanding the mechanism of action of IAP may help in minimizing neonatal evaluation and unnecessary antibiotic use.Areas covered: In recent years, several studies on pharmacokinetics and clinical use of IAP have been published. Although penicillin and ampicillin are the most preferred antibiotics, the clinical efficacy of non-beta-lactam antibiotics, including clindamycin and vancomycin, used in cases of penicillin anaphylaxis-associated allergy, remains debatable. This is a narrative review of the literature regarding the impact of 'inadequate' IAP on the clinical management of women and newborns.Expert opinion: Recent evidence suggests that 'inadequate' IAP with beta-lactams is more effective in preventing vertical transmission of GBS than previously thought. Newborns exposed to intrapartum beta-lactams and who are asymptomatic at birth are likely uninfected, irrespective of IAP duration before delivery. Hence, we may abandon the concept of 'inadequate' IAP with beta-lactams in early-onset GBS sepsis, relying primarily on clinical signs observed at birth for managing IAP-exposed neonates.

The value of amniotic fluid analysis in patients with suspected clinical chorioamnionitis

Objective To assess the value of incorporating amniotic fluid (AF) analysis in the management of patients with clinical chorioamnionitis. Methods This was a retrospective cohort study of all women carrying a singleton fetus and managed at our center between 2000 and 2009. We included only those women suspected of chorioamnionitis based on one or more of the following: (1) uterine tenderness, (2) maternal fever, (3) maternal and/or fetal tachycardia and (4) purulent discharge. The management was deemed to be justified if (1) pregnancy was terminated <24 weeks and histology confirmed chorioamnionitis; (2) delivery was performed expeditiously after initial assessment and histology confirmed chorioamnionitis; (3) delivery was delayed for 2-7 days and the patient completed a course of antenatal steroids before 34 weeks; and (4) delivery was delayed ≥7 days and histology was not indicative of chorioamnionitis, or delivery occurred after 37 weeks. Univariate and logistic regression analyses were used as appropriate. Results Of the 77 women with suspected chorioamnionitis, AF analysis was performed in 43 (55.8%) cases, and the management was justified in 63 (81.8%) cases based on the aforementioned criteria. Stepwise regression analysis confirmed AF analysis as a predictor of justified management. The rates of composite morbidity, neonatal sepsis, neonatal death and admissions to neonatal intensive care unit were lower in the justified management group. Conclusion Incorporation of AF analysis into clinical assessment does improve the management of suspected chorioamnionitis.

Risk factors for group B streptococcus early-onset disease: an Italian, area-based, case-control study

Purpose: Intrapartum antibiotic prophylaxis (IAP) prevents group B streptococcus (GBS) early-onset disease (EOD). No European study evaluates the relative impact of risk factors (RFs) for EOD after a screening-based strategy and widespread IAP use We aimed to evaluate the risks of EOD in an Italian region where a screening-based strategy for preventing EOD was implemented.Materials and methods: Cases of EOD born at or above 35 weeks' gestation were reviewed and matched with controls.Results: There were 109 cases of EOD among 532,154 live births. Most cases had negative GBS prenatal screening (56/91, 61.5%) and were unexposed to IAP (86/109, 78.9%). At multivariate analysis, GBS bacteriuria (OR = 6.99), positive prenatal screening (OR = 13.7) and maternal intrapartum fever (OR = 188.3) were associated with an increased risk of EOD, whereas intrapartum beta-lactam antibiotics were associated with a decreased risk of EOD (≥4 h: OR = 0.008; <4 h: OR = 0.04). Neonates born to nonfebrile, GBS positive pregnant women, receiving beta-lactam antibiotics had very low probability of EOD, particularly if IAP was adequate.Conclusions: GBS positive prenatal screening, GBS bacteriuria and intrapartum fever are associated with EOD. Intrapartum beta-lactam antibiotics reduce the probability of EOD in neonates born to nonfebrile mothers.

Early onset sepsis calculator-based management of newborns exposed to maternal intrapartum fever: a cost benefit analysis

OBJECTIVE

To determine potential net monetary benefit of an early onset sepsis calculator-based approach for management of neonates exposed to maternal intrapartum fever, compared to existing guidelines.

STUDY DESIGN

We performed a cost-benefit analysis comparing two management approaches for newborns >34 weeks gestational age exposed to maternal intrapartum fever. Probabilities of sepsis and meningitis, consequences of infection and antibiotic use, direct medical costs, and indirect costs for long-term disability and mortality were considered.

RESULTS

A calculator-based approach resulted in a net monetary benefit of $3998 per infant with a 60% likelihood of net benefit in probabilistic sensitivity analysis. Our model predicted a 67% decrease in antibiotic use in the calculator arm. The absolute difference for all adverse clinical outcomes between approaches was ≤0.6%.

CONCLUSIONS

Compared to existing guidelines, a calculator-based approach for newborns exposed to maternal intrapartum fever yields a robust net monetary benefit, largely by preventing unnecessary antibiotic treatment.

Group B Streptococcus early-onset disease and observation of well-appearing newborns

Background

International guidelines lack a substantial consensus regarding management of asymptomatic full-term and late preterm neonates at risk for early-onset disease (EOS). Large cohorts of newborns are suitable to increase the understanding of the safety and efficacy of a given strategy.

Methods

This is a prospective, area-based, cohort study involving regional birth facilities of Emilia-Romagna (Italy). We compared cases of EOS (at or above 35 weeks’ gestation) registered in 2003–2009 (baseline period: 266,646 LBs) and in 2010–2016, after introduction of a new strategy (serial physical examinations, SPEs) for managing asymptomatic neonates at risk for EOS (intervention period: 265,508 LBs).

Results

There were 108 cases of EOS (baseline period, n = 60; intervention period, n = 48). Twenty-two (20.4%) remained asymptomatic through the first 72 hours of life, whereas 86 (79.6%) developed symptoms, in most cases (52/86, 60.5%) at birth or within 6 hours. The median age at presentation was significantly earlier in the intrapartum antibiotic prophylaxis (IAP)-exposed than in the IAP-unexposed neonates (0 hours, IQR 0.0000–0.0000 vs 6 hours, IQR 0.0000–15.0000, p<0.001). High number of neonates (n = 531) asymptomatic at birth, exposed to intrapartum fever, should be treated empirically for each newborn who subsequently develops sepsis. IAP exposed neonates increased (12% vs 33%, p = 0.01), age at presentation decreased (median 6 vs 1 hours, p = 0.01), whereas meningitis, mechanical ventilation and mortality did not change in baseline vs intervention period. After implementing the SPEs, no cases had adverse outcomes due to the strategy, and no cases developed severe disease after 6 hours of life.

Conclusions

Infants with EOS exposed to IAP developed symptoms at birth in almost all cases, and those who appeared well at birth had a very low chance of having EOS. The risk of EOS in neonates (asymptomatic at birth) exposed to intrapartum fever was low. Although definite conclusions on causation are lacking, our data support SPEs of asymptomatic newborns at risk for EOS. SPEs seems a safe and effective alternative to laboratory screening and empirical antibiotic therapy.

Review article: Neonatal Sepsis in Thailand

Neonatal sepsis is a burden around the world and causes high mortality and morbidity as well. Long-term neurodevelopmental disability may occur in survivors. General physicians, pediatricians, and neonatologists need be attentive to the proper diagnosis, starting, de-escalating or stopping empirical antimicrobials therapy in neonatal sepsis. Furthermore, multidrug resistant organisms have emerged among adults, children, and neonates in developing countries. Local epidemiology studies and antimicrobial stewardship programs are important for application of the best and specific treatments. Knowledge, definitions, and clinical practice of neonatal sepsis are updated in this review.

Inflammation induced preterm labor and birth

Preterm birth which occurs before 37 weeks gestation is one of the most common obstetrical complication in humans. After many studies, it appears that "not one answer fits all" regarding the risk factors, causes and the treatments for this syndrome. However, it is becoming more evident that one of the major risk factors is inflammation and/or infection in the fetoplacental unit. In animal models (usually consisting of mice injected with lipopolysaccharide at 14 days of gestation), IL-22 and IL-6 have been identified as factors related to preterm birth. There are some clinical tests available to determine the risk for preterm labor and delivery, which can be identified before, during early, or at mid-gestation. However, treatment of preterm birth with antibiotics so far has not been "curable" and studies using anti-inflammatory treatments are not readily available. More studies regarding causes and treatments for preterm labor and delivery in humans are necessary to prevent neonatal deaths and/or developmental abnormalities associated with this common syndrome.

Sepsis and Oxidative Stress in the Newborn: From Pathogenesis to Novel Therapeutic Targets

Sepsis is at present one of the leading causes of morbidity and mortality in the neonatal population. Together with inflammation, oxidative stress is involved in detrimental pathways activated during neonatal sepsis, eventually leading to organ dysfunction and death. The redox cascade during sepsis is mainly initiated by IL-6 and IL-8 stimulation in newborns and includes multiple noxious processes, as direct cell damage induced by reactive oxygen species, activation of gene expression leading to amplification of inflammation and oxidative stress, and impairment of mitochondrial function. Once proinflammatory and prooxidant pathways are established as stimulated by causing pathogens, self-maintaining unfavorable redox cycles ensue, leading to oxidative stress-related cellular damage, independently from the activating pathogens themselves. Despite antioxidant systems are induced during neonatal sepsis, as an adaptive response to an increased oxidative burden, a condition of redox imbalance favoring oxidative pathways occurs, resulting in increased markers of oxidative stress damage. Therefore, antioxidant treatment would exert beneficial effects during neonatal sepsis, potentially interrupting prooxidant pathways and preventing the maintenance of detrimental redox cycles that cannot be directly affected by antibiotic treatment. Among others, antioxidant agents investigated in clinical settings as adjunct treatment for neonatal sepsis include melatonin and pentoxifylline, both showing promising results, while novel antioxidant molecules, as edaravone and endothelin receptor antagonists, are at present under investigation in animal models. Finally, mitochondria-targeted antioxidant treatments could represent an interesting line of research in the treatment of neonatal sepsis.

Maternal Glucose Supplementation in a Murine Model of Chorioamnionitis Alleviates Dysregulation of Autophagy in Fetal Brain

Fetal brain injury induced by intrauterine inflammation is a major risk factor for adverse neurological outcomes, including cerebral palsy, cognitive dysfunction, and behavioral disabilities. There are no adequate therapies for neuronal protection to reduce fetal brain injury, especially new strategies that may apply promptly and conveniently. In this study, we explored the effect of maternal glucose administration in a mouse model of intrauterine inflammation at term. Our results demonstrated that maternal glucose supplementation significantly increased survival birth rate and improved the neurobehavioral performance of pups exposed to intrauterine inflammation. Furthermore, we demonstrated that maternal glucose administration improved myelination and oligodendrocyte development in offspring exposed to intrauterine inflammation. Though the maternal blood glucose concentration was temporally prevented from decrease induced by intrauterine inflammation, the glucose concentration in fetal brain was not recovered by maternal glucose supplementation. The adenosine triphosphate (ATP) level and autophagy in fetal brain were regulated by maternal glucose supplementation, which may prevent dysregulation of cellular metabolism. Our study is the first to provide evidence for the role of maternal glucose supplementation in the cell survival of fetal brain during intrauterine inflammation and further support the possible medication with maternal glucose treatment.

Strategies for preventing early-onset sepsis and for managing neonates at-risk: wide variability across six Western countries

Objective: Group B streptococcus (GBS) early-onset sepsis (EOS) has declined after widespread intrapartum antibiotic prophylaxis. However, strategies for preventing EOS may differ across countries. The analysis of their strategies allows to compare the effectiveness of prevention in different countries and suggests opportunities for improvement. Methods: We compared six western countries. Prevention strategies, incidence rates of EOS and approaches for managing neonates at-risk were analysed. Countries were selected because of availability of recommendations for prevention and sufficient epidemiological data for comparison. Results: Five of six countries recommend antenatal vagino-rectal screening. The decline of GBS cases is relevant in most countries, particularly in those with a screening-based strategy, which have reached incidence rates from 0.1 to 0.3/1000 live births and zero or close to zero mortality in full-term newborns. The recommendation for managing asymptomatic neonates at risk for EOS varies according to gestational age and ranges from observation only to laboratory testing plus empirical antibiotics. Chorioamnionitis (suspected or confirmed) is the main indication for carry out laboratory testing and for administering empirical antibiotics. Conclusions: Wide variations exists in preventing EOS. They depend on national epidemiology of GBS infections, compliance, cost, and feasibility of the strategy. The extreme variability of approaches for managing neonates at risk for EOS reflects the even greater uncertainty regarding this issue, and may explain the persisting, great use of resources to prevent a disease that has become very rare nowadays.

Antibiotic stewardship in perinatal and neonatal care

The spread of antibiotic resistance due to the use and misuse of antibiotics around the world is now a major health crisis. Neonates are exposed to antibiotics both before and after birth, often empirically because of risk factors for infection, or for non-specific signs which may or may not indicate sepsis. There is increasing evidence that, apart from antibiotic resistance, the use of antibiotics in pregnancy and in the neonatal period alters the microbiome in the fetus and neonate with an increased risk of immediate and long-term adverse effects. Antibiotic stewardship is a co-ordinated program that promotes the appropriate use of antibiotics, improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms. This review addresses some of the controversies in antibiotic use in the perinatal period, examines opportunities for reduction of unnecessary antibiotic exposure in neonates, and provides a framework for antibiotic stewardship in neonatal care.