Chorioamnionitis: a risk factor for fetal and neonatal morbidity

Mild/asymptomatic COVID-19 in unvaccinated pregnant mothers impairs neonatal immune responses

Maternal SARS-CoV-2 infection triggers placental inflammation and alters cord blood immune cell composition. However, most studies focus on outcomes of severe maternal infection. Therefore, we analyzed cord blood and chorionic villi from newborns of unvaccinated mothers who experienced mild/asymptomatic SARS-CoV-2 infection during pregnancy. We investigated immune cell rewiring using flow cytometry, single-cell RNA sequencing, and functional readouts using ex vivo stimulation with TLR agonists and pathogens. Maternal infection was associated with increased frequency of memory T and B cells and nonclassical monocytes in cord blood. Ex vivo T and B cell responses to stimulation were attenuated, suggesting a tolerogenic state. Maladaptive responses were also observed in cord blood monocytes, where antiviral responses were dampened but responses to bacterial TLRs were increased. Maternal infection was also associated with expansion and activation of placental Hofbauer cells, secreting elevated levels of myeloid cell-recruiting chemokines. Moreover, we reported increased activation of maternally derived monocytes/macrophages in the fetal placenta that were transcriptionally primed for antiviral responses. Our data indicate that even in the absence of vertical transmission or symptoms in the neonate, mild/asymptomatic maternal COVID-19 altered the transcriptional and functional state in fetal immune cells in circulation and in the placenta.

Prenatal exposure to nitrate from drinking water and the risk of preterm birth

Evidence is emerging that preterm birth (PTB, birth before 37 completed weeks of gestation), a risk factor for neonatal mortality and future morbidity, may be induced by maternal nitrate (NO3−) exposure from drinking water. The objective of this study is to assess the association between maternal exposure to nitrate and the risk of PTB in a nationwide study of liveborn singletons.

Outpatient Antibiotic Prescriptions in Pregnant Women in Małopolska Province

Background: excessive and incorrect use of antibiotics is a common event that contributes to increased bacterial resistance to antibiotics. Based on the European Centre for Disease Control and Prevention (ECDC) European Surveillance of Antimicrobial Consumption (ESAC)-Net reports, outpatient antibiotics prescribing in Poland, is higher than the European average rate. However, ECDC reports do not provide data on consumption in specific patient groups. Additional studies focused on selected patient groups are needed for a more detailed analysis. The use of antibiotics during pregnancy is inevitable due to the proven risk of complications in this period, perinatal infections, and infections in newborns, in the situation of frequent infections of the genital tract, urinary tract, and asymptomatic bacteriuria in pregnant women. The aim of this study was to analyze the use of antibiotics/the implementation of antibiotic prescriptions ordered by gynecologists during pregnancy in pregnant women in Małopolska Voivodeship, with particular emphasis on demographic data and drug groups. Material and methods: the analysis used data on the reimbursement of antibiotics from the Małopolska Health Fund for 2013–2014. The database contained information of a demographic nature: age, place of residence, date of birth, as well as information on the type of drug, and the number of packages purchased by the patients. Results: the study included 67,917 women. During pregnancy, 23.6% filled their prescriptions for antibiotics. In the first trimester, the percentage of women filling their prescriptions for antibiotics was the lowest and amounted to 7.8%, in the second and third trimesters, these were 9.0% and 11.2%, respectively. The inhabitants of rural areas bought antibiotics more often (23.5%). Most frequently, antibiotics were purchased by women under 18 years of age (32.1%), but the use of antibiotics in women aged 18–34 and over 35 was similar, amounting to 23.8% and 22.7%, respectively. Most often (94.78% of cases) monotherapy was used, including beta-lactams and beta-lactams with an inhibitor (67.3%), then second-generation cephalosporins (13.5%), macrolides (14.73%), and others. Prescription of two different preparations was found in 5.06% of cases, three (0.19%), and four or more (0.03%). Conclusions: due to the fact that studies on antibiotic therapy in pregnant women in Poland are rare, it is impossible to assess the situation thoroughly. Additionally, in Poland, the prevalence of gestational infections is unknown, and their diagnostics is important, especially in relation to microbiological diagnostics and targeted treatment. However, the present results indicate the need to implement broad health promotion programs, accessible to all women, also those living outside large cities, particularly promoting the prevention of urinary tract infections and reproductive health in general.

Amphiregulin Regulates Phagocytosis-Induced Cell Death in Monocytes via EGFR and the Bcl-2 Protein Family

Neonates are extremely susceptible to bacterial infections, and evidences suggest that phagocytosis-induced cell death (PICD) is less frequently triggered in neonatal monocytes than in monocytes from adult donors. An insufficient termination of the inflammatory response, leading to a prolonged survival of neonatal monocytes with ongoing proinflammatory cytokine release, could be associated with the progression of various inflammatory diseases in neonates. Our previous data indicate that amphiregulin (AREG) is increasingly expressed on the cell surface of neonatal monocytes, resulting in remarkably higher soluble AREG levels after proteolytic shedding. In this study, we found that E. coli-infected neonatal monocytes show an increased phosphorylation of ERK, increased expression of Bcl-2 and Bcl-X_L, and reduced levels of cleaved caspase-3 and caspase-9 compared to adult monocytes. In both cell types, additional stimulation with soluble AREG further increased ERK activation and expression of Bcl-2 and Bcl-X_L and reduced levels of cleaved caspase-3 and caspase-9 in an EGFR-dependent manner. These data suggest that reduced PICD of neonatal monocytes could be due to reduced intrinsic apoptosis and that AREG can promote protection against PICD. This reduction of the intrinsic apoptosis pathway in neonatal monocytes could be relevant for severely prolonged inflammatory responses of neonates.

The Elusive Role of Placental Macrophages: The Hofbauer Cell

In this review, we discuss the often overlooked tissue-resident fetal macrophages, Hofbauer cells, which are found within the chorionic villi of the human placenta. Hofbauer cells have been shown to have a phenotype associated with regulatory and anti-inflammatory functions. They are thought to play a crucial role in the regulation of pregnancy and in the maintenance of a homeostatic environment that is crucial for fetal development. Even though the numbers of these macrophages are some of the most abundant immune cells in the human placenta, which are sustained throughout pregnancy, there are very few studies that have identified their origin, their phenotype, and functions and why they are maintained throughout gestation. It is not yet understood how Hofbauer cells may change in function throughout normal pregnancy, and especially in those complicated by maternal gestational diabetes, preeclampsia, and viral infections, such as Zika, cytomegalovirus, and human immunodeficiency virus. We review what is known about the origin of these macrophages and explore how common complications of pregnancy dysregulate these cells leading to adverse birth outcomes in humans. Our synthesis sheds light on areas for human studies that can further define these innate regulatory cells.

Amphiregulin Regulates Phagocytosis-Induced Cell Death in Monocytes via EGFR and Matrix Metalloproteinases

Neonates are highly susceptible to microbial infections which is partially attributable to fundamental phenotypic and functional differences between effector cells of the adult and neonatal immune system. The resolution of the inflammation is essential to return to tissue homeostasis, but given that various neonatal diseases, such as periventricular leukomalacia, necrotizing enterocolitis, or bronchopulmonary dysplasia, are characterized by sustained inflammation, newborns seem predisposed to a dysregulation of the inflammatory response. Targeted apoptosis of effector cells is generally known to control the length and extent of the inflammation, and previous studies have demonstrated that phagocytosis-induced cell death (PICD), a special type of apoptosis in phagocytic immune cells, is less frequently triggered in neonatal monocytes than in adult monocytes. We concluded that a rescue of monocyte PICD could be a potential therapeutic approach to target sustained inflammation in neonates. The EGFR ligand amphiregulin (AREG) is shed in response to bacterial infection and was shown to mediate cellular apoptosis resistance. We hypothesized that AREG might contribute to the reduced PICD of neonatal monocytes by affecting apoptosis signaling. In this study, we have examined a cascade of signaling events involved in extrinsic apoptosis by using a well-established in vitro E. coli infection model in monocytes from human peripheral blood (PBMO) and cord blood (CBMO). We found that CBMO shows remarkably higher pro-AREG surface expression as well as soluble AREG levels in response to infection as compared to PBMO. AREG increases intracellular MMP-2 and MMP-9 levels and induces cleavage of membrane-bound FasL through engagement with the EGF receptor. Our results demonstrate that loss of AREG rescues PICD in CBMO to the level comparable to adult monocytes. These findings identify AREG as a potential target for the prevention of prolonged inflammation in neonates.

Reduced internalization of TNF-ɑ/TNFR1 down-regulates caspase dependent phagocytosis induced cell death (PICD) in neonatal monocytes

Phagocytosis-induced cell death (PICD) is diminished in cord blood monocytes (CBMO) as compared to cells from adults (PBMO) due to differences in the CD95-pathway. This may support a prolonged pro-inflammatory response with sequels of sustained inflammation as seen in neonatal sepsis. Here we hypothesized that TNF-α mediated induction of apoptosis is impaired in CBMO due to differences in the TNFR1-dependent internalization. Monocytes were infected with Escherichia coli-GFP (E. coli-GFP). Monocyte phenotype, phagocytic activity, induction of apoptosis, and TNF-α/TNF-receptor (TNFR) -expression were analysed. In the course of infection TNF-α-secretion of CBMO was reduced to 40% as compared to PBMO (p<0.05). Neutralization of TNF-α by an αTNF-α antibody reduced apoptotic PICD in PBMO four-fold (p < 0.05 vs. infection with E. coli). PICD in CBMO was reduced 5-fold compared to PBMO and showed less responsiveness to αTNF-α antibody. CBMO expressed less pro-apoptotic TNFR1, which, after administration of TNF-α or infection with E. coli was internalized to a lesser extent. With similar phagocytic capacity, reduced TNFR1 internalization in CBMO was accompanied by lower activation of caspase-8 (p < 0.05 vs. PBMO). Stronger caspase-8 activation in PBMO caused more activation of effector caspase-3 and apoptosis (all p < 0.05 vs. PBMO). Our results demonstrate that TNFR1 internalization is critical in mediating PICD in monocytes after infection with E.coli and is reduced in CBMO.

The role of oxidative stress, inflammation and acetaminophen exposure from birth to early childhood in the induction of autism

The wide range of factors associated with the induction of autism is invariably linked with either inflammation or oxidative stress, and sometimes both. The use of acetaminophen in babies and young children may be much more strongly associated with autism than its use during pregnancy, perhaps because of well-known deficiencies in the metabolic breakdown of pharmaceuticals during early development. Thus, one explanation for the increased prevalence of autism is that increased exposure to acetaminophen, exacerbated by inflammation and oxidative stress, is neurotoxic in babies and small children. This view mandates extreme urgency in probing the long-term effects of acetaminophen use in babies and the possibility that many cases of infantile autism may actually be induced by acetaminophen exposure shortly after birth.

Antenatal Suppression of IL-1 Protects against Inflammation-Induced Fetal Injury and Improves Neonatal and Developmental Outcomes in Mice

Preterm birth (PTB) is commonly accompanied by in utero fetal inflammation, and existing tocolytic drugs do not target fetal inflammatory injury. Of the candidate proinflammatory mediators, IL-1 appears central and is sufficient to trigger fetal loss. Therefore, we elucidated the effects of antenatal IL-1 exposure on postnatal development and investigated two IL-1 receptor antagonists, the competitive inhibitor anakinra (Kineret) and a potent noncompetitive inhibitor 101.10, for efficacy in blocking IL-1 actions. Antenatal exposure to IL-1β induced Tnfa, Il6, Ccl2, Pghs2, and Mpges1 expression in placenta and fetal membranes, and it elevated amniotic fluid IL-1β, IL-6, IL-8, and PGF_2α, resulting in PTB and marked neonatal mortality. Surviving neonates had increased Il1b, Il6, Il8, Il10, Pghs2, Tnfa, and Crp expression in WBCs, elevated plasma levels of IL-1β, IL-6, and IL-8, increased IL-1β, IL-6, and IL-8 in fetal lung, intestine, and brain, and morphological abnormalities: e.g., disrupted lung alveolarization, atrophy of intestinal villus and colon-resident lymphoid follicle, and degeneration and atrophy of brain microvasculature with visual evoked potential anomalies. Late gestation treatment with 101.10 abolished these adverse outcomes, whereas Kineret exerted only modest effects and no benefit for gestation length, neonatal mortality, or placental inflammation. In a LPS-induced model of infection-associated PTB, 101.10 prevented PTB, neonatal mortality, and fetal brain inflammation. There was no substantive deviation in postnatal growth trajectory or adult body morphometry after antenatal 101.10 treatment. The results implicate IL-1 as an important driver of neonatal morbidity in PTB and identify 101.10 as a safe and effective candidate therapeutic.

Biomarkers for Bronchopulmonary Dysplasia in the Preterm Infant

Bronchopulmonary dysplasia (BPD) is a chronic inflammatory lung disease of very-low-birth-weight (VLBW) preterm infants, associated with arrested lung development and a need for supplemental oxygen. Over the past few decades, the incidence of BPD has significantly raised as a result of improved survival of VLBW infants requiring mechanical ventilation. While early disease detection is critical to prevent chronic lung remodeling and complications later in life, BPD is often difficult to diagnose and prevent due to the lack of good biomarkers for identification of infants at risk, and overlapping symptoms with other diseases, such as pulmonary hypertension (PH). Due to the current lack of effective treatment available for BPD and PH, research is currently focused on primary prevention strategies, and identification of biomarkers for early diagnosis, that could also represent potential therapeutic targets. In addition, novel histopathological, biochemical, and molecular factors have been identified in the lung tissue and in biological fluids of BPD and PH patients that could associate with the disease phenotype. In this review, we provide an overview of biomarkers for pediatric BPD and PH that have been identified in clinical studies using various biological fluids. We also present a brief summary of the information available on current strategies and guidelines to prevent and diagnose BPD and PH, as well as their pathophysiology, risk factors, and experimental therapies currently available.

LPS- and LTA-induced expression of IL-6 and TNF-α in neonatal and adult blood: role of MAPKs and NF-κB

As nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) seem to be critical mediators in the inflammatory response, we studied the effects of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) on (a) the activation of NF-κB and MAPKs and (b) the expression of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) with or without the specific inhibitors of these intracellular signal transduction pathways in neonatal cord and adult blood. TNF-α and IL-6 concentrations showed a sharp increase in the supernatants of cord and adult whole blood after stimulation. TNF-α concentrations were significantly higher, whereas IL-6 concentrations were tendentially lower in adult blood after stimulation. Stimulation with LPS or LTA resulted in a significantly decreased activation of p38 MAPK in neonatal compared with adult blood. Although LTA failed to induce additional ERK1/2 phosphorylation, LPS stimulation mediated the moderately increased levels of activated ERK1/2 in neonatal monocytes. The addition of the p38 MAPK inhibitor SB202190 significantly decreased IL-6 and TNF-α production upon LPS or LTA stimulation. Furthermore, the inhibition of ERK1/2 was able to reduce LPS-stimulated TNF-α production in neonatal blood. We conclude that p38 MAPK as well as ERK1/2 phosphorylation is crucially involved in LPS activation and could explain the differences in early cytokine response between neonatal and adult blood.

Morbidity and mortality among very-low-birth-weight infants born to mothers with clinical chorioamnionitis

BACKGROUND

Controversy exists about the relationship between maternal inflammation and the development of different morbidities and mortality in the newborn. We aimed to establish the incidence of clinical chorioamnionitis in our Neonatal Intensive Care Unit and its relation to morbidity and mortality among very-low-birth-weight infants.

METHODS

This was an observational study of a cohort of very-low-birth-weight neonates admitted to our Neonatal Intensive Care Unit, between January 2008 and December 2012. Demographic characteristics and outcomes were analyzed and a comparison between exposed and non-exposed infants was carried out.

RESULTS

During the study period, 451 very-low-birth-weight infants were admitted to our Neonatal Intensive Care Unit, and 31 (6.87%) were exposed to maternal clinical chorioamnionitis. The incidence was higher at lower gestational ages: 13.2% (23-26 weeks), 8.1% (27-30 weeks), and 2.6% (31-34 weeks) (p = 0.022). After correcting by gestational age and birth weight, early-onset neonatal sepsis (adjusted relative risk = 6.13; 95% confidence interval = 1.67-22.58; p = 0.006) and periventricular leukomalacia (adjusted relative risk = 24.62; 95% confidence interval = 1.87-324.28; p = 0.015) were significantly associated with maternal clinical chorioamnionitis. There were no differences in mortality or in survival without major morbidity.

CONCLUSION

Clinical chorioamnionitis confers an increased risk of early-onset neonatal sepsis and periventricular leukomalacia to exposed very-low-birth-weight infants.

Oxidative stress and bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the major cause of pulmonary disease in infants. The pathophysiology and management of BPD changed with the improvement of neonatal intensive care unit (NICU) management and with the increase of survival rates. Despite the improvements made, BPD is still a public health concern, resulting in frequent hospitalizations with high rates of mortality, impaired weight and height growth, and neurodevelopmental disorders. Lung injury in the neonatal period has multiple etiologic factors - genetic, hemodynamic, metabolic, nutritional, mechanical, and infectious mechanisms - act in a cumulative and synergic way. Free radical (FR) generation is largely recognized as the major cause of lung damage. Oxidative stress (OS) is the final common endpoint for a complex convergence of events, some genetically determined and some triggered by in utero stressors. Inflammatory placental disorders and chorioamnionitis also play an important role due to the coexistence of inflammatory and oxidative lesions. In addition, the contribution of airway inflammation has been extensively studied. The link between inflammation and OS injury involves the direct activation of inflammatory cells, especially granulocytes, which potentiates the inflammatory reaction. Individualized interventions to support ventilation, minimize oxygen exposure, minimize apnea, and encourage growth should decrease both the frequency and severity of BPD. Future perspectives suggest supplementation with enzymatic and/or non-enzymatic antioxidants. The use of antioxidants in preterm newborns particularly exposed to OS and at risk for BPD represents a logical strategy to ameliorate FRs injury, but further studies are needed to support this hypothesis.

Infection-induced inflammation and cerebral injury in preterm infants

Preterm birth and infectious diseases are the most common causes of neonatal and early childhood deaths worldwide. The rates of preterm birth have increased over recent decades and account for 11% of all births worldwide. Preterm infants are at significant risk of severe infection in early life and throughout childhood. Bacteraemia, inflammation, or both during the neonatal period in preterm infants is associated with adverse outcomes, including death, chronic lung disease, and neurodevelopmental impairment. Recent studies suggest that bacteraemia could trigger cerebral injury even without penetration of viable bacteria into the CNS. Here we review available evidence that supports the concept of a strong association between bacteraemia, inflammation, and cerebral injury in preterm infants, with an emphasis on the underlying biological mechanisms, clinical correlates, and translational opportunities.

The diagnostic performance of the Mass Restricted (MR) score in the identification of microbial invasion of the amniotic cavity or intra-amniotic inflammation is not superior to amniotic fluid interleukin-6

OBJECTIVE

Intra-amniotic infection/inflammation are major causes of spontaneous preterm labor and delivery. However, diagnosis of intra-amniotic infection is challenging because most are subclinical and amniotic fluid (AF) cultures take several days before results are available. Several tests have been proposed for the rapid diagnosis of microbial invasion of the amniotic cavity (MIAC) or intra-amniotic inflammation. The aim of this study was to examine the diagnostic performance of the AF Mass Restricted (MR) score in comparison with interleukin-6 (IL-6) and matrix metalloproteinase-8 (MMP-8) for the identification of MIAC or inflammation.

METHODS

AF samples were collected from patients with singleton gestations and symptoms of preterm labor (n = 100). Intra-amniotic inflammation was defined as >100 white blood cells/mm(3) (WBCs) in AF; MIAC was defined as a positive AF culture. AF IL-6 and MMP-8 were determined using ELISA. The MR score was obtained using the Surface-Enhanced Laser Desorption Ionization Time of Flight (SELDI-TOF) mass spectrometry. Sensitivity and specificity were calculated and logistic regression models were fit to construct receiver-operating characteristic (ROC) curves for the identification of each outcome. The McNemar's test and paired sample non-parametric statistical techniques were used to test for differences in diagnostic performance metrics.

RESULTS

(1) The prevalence of MIAC and intra-amniotic inflammation was 34% (34/100) and 40% (40/100), respectively; (2) there were no significant differences in sensitivity of the three tests under study (MR score, IL-6 or MMP-8) in the identification of either MIAC or intra-amniotic inflammation (using the following cutoffs: MR score >2, IL-6 >11.4 ng/mL, and MMP-8 >23 ng/mL); (3) there was no significant difference in the sensitivity among the three tests for the same outcomes when the false positive rate was fixed at 15%; (4) the specificity for IL-6 was not significantly different from that of the MR score in identifying either MIAC or intra-amniotic inflammation when using previously reported thresholds; and (5) there were no significant differences in the area under the ROC curve when comparing the MR score, IL-6 or MMP-8 in the identification of these outcomes.

CONCLUSIONS

IL-6 and the MR score have equivalent diagnostic performance in the identification of MIAC or intra-amniotic inflammation. Selection from among these three tests (MR score, IL-6 and MMP-8) for diagnostic purposes should be based on factors such as availability, reproducibility, and cost. The MR score requires a protein chip and a SELDI-TOF instrument which are not widely available or considered "state of the art". In contrast, immunoassays for IL-6 can be performed in the majority of clinical laboratories.

Interleukin-1 receptor blockade in perinatal brain injury

Interleukin-1 (IL-1) is a potent inflammatory cytokine that can be produced by a variety of cell types throughout the body. While IL-1 is a central mediator of inflammation and response to infection, the role of IL-1 signaling in adult and pediatric brain injury is becoming increasingly clear. Although the mechanisms of IL-1 expression are largely understood, the downstream effects and contributions to excitotoxicity and oxidative stress are poorly defined. Here, we present a review of mechanisms of IL-1 signaling with a focus on the role of IL-1 in perinatal brain injury. We highlight research models of perinatal brain injury and the use of interleukin-1 receptor antagonist (IL-1RA) as an agent of therapeutic potential in preventing perinatal brain injury due to exposure to inflammation.

Outcomes of very-low-birth-weight infants exposed to maternal clinical chorioamnionitis: a multicentre study

BACKGROUND

Chorioamnionitis is a recognized risk factor of preterm delivery; however, controversy still persists concerning the relationship between maternal inflammation and neonatal morbidity and mortality.

OBJECTIVE

To determine the incidence of clinical chorioamnionitis and its relationship to morbidity and mortality among very-low-birth-weight (VLBW) infants.

METHODS

This was a retrospective analysis of prospectively collected data of VLBW neonates ≤ 32 weeks' gestational age (GA) admitted to collaborating units in the Spanish SEN1500 Network between January 2008 and December 2011. Clinical chorioamnionitis was defined by obstetricians based on clinical findings, and neonatal outcomes were compared between exposed and non-exposed infants by multivariate logistic regression analysis.

RESULTS

During the study period, 11,464 VLBW newborns were admitted to our units and 10,026 were ≤ 32 weeks' GA. Among them, 8,330 (83.1%) had complete data and were included. Of these, 1,480 (17.8%) were exposed to maternal clinical chorioamnionitis. The incidence was higher at lower GA and, after adjusting for confounding factors, exposed infants had higher risks of early-onset neonatal sepsis (EONS) (10.0 vs. 2.8%; aOR 3.102; 95% CI 2.306-4.173; p < 0.001) and necrotizing enterocolitis (NEC) (11.2 vs. 7.7%; aOR 1.300; 95% CI 1.021-1.655; p < 0.033), but lower risks of patent ductus arteriosus (PDA) (43.2 vs. 34.9%; aOR 0.831; 95% CI 0.711-0.971; p < 0.02) and late-onset bacterial sepsis (LONS) (36.6 vs. 32.5%; aOR 0.849; 95% CI 0.729-0.989; p < 0.035). There were no differences in mortality between the groups.

CONCLUSIONS

The incidence of maternal clinical chorioamnionitis is inversely related to GA at delivery, and in VLBW infants ≤ 32 weeks' GA it is associated with higher risks of EONS and NEC, but lower risks of PDA and LONS. We did not found differences in survival.

The association between histological chorioamnionitis, funisitis and neonatal outcome in women with preterm prelabor rupture of membranes

OBJECTIVE

To determine the impact of histological chorioamnionitis (HCA) and funisitis on neonatal outcome in preterm prelabor rupture of membranes (PPROM) pregnancies.

METHODS

Women with PPROM between 24 + 0 to 36 + 6 weeks of gestation, admitted to the Department of Obstetrics and Gynecology at the University Hospital Hradec Kralove in the Czech Republic, between July 2008 and October 2010, were enrolled in the study (n = 231).

RESULTS

The incidence of early-onset sepsis (EOS) differed significantly in neonates born to women with and without HCA, after adjustment for gestational age (11% versus 1%, p = 0.011). The incidence of EOS in neonates was also significantly different, after adjustment for gestational age, in cases with and without funisitis (18% versus 4%, p = 0.002). The same was also found for retinopathy of prematurity (ROP) cases with and without funisitis (23% versus 4%, p = 0.014), after adjustment for gestational age.

CONCLUSIONS

HCA and funisitis increase the risk of adverse perinatal outcome in PPROM pregnancies.

Risk factors for acute respiratory morbidity in moderately preterm infants

BACKGROUND

Infants born preterm account for a substantial part of neonatal morbidity, with acute respiratory disorders being a dominating clinical problem. Whereas focus in recent studies has been on extremely and very preterm infants, less is known about contemporary rates and risk factors for acute respiratory morbidity in moderately and late preterm infants. The objective of this population-based Swedish study was to establish rates for different acute respiratory diseases in moderately preterm infants, and to identify maternal, obstetric and neonatal risk factors for the two most common diagnoses, transient tachypnoea of the newborn (TTN) and respiratory distress syndrome (RDS).

METHODS

The study included 4679 moderately preterm [gestational age (GA): 30 to 34 weeks], 15 036 late preterm infants (GA 35 to 36 weeks) and 451 479 term infants (GA: 37 to 41 weeks). All infants were born in 2004-2008.

RESULTS

In moderately preterm infants, risk factors for TTN in multivariable analyses were multiparity, caesarean section before and after onset of labour, male sex, Apgar score 4-6 at 5 min and lower GA. Risk factors for RDS were multiparity, caesarean section before and after onset of labour, male sex, Apgar score <7 at 5 min and lower GA. Preterm rupture of membranes, antenatal corticosteroid treatment and being small for gestational age reduced the risk of RDS.

CONCLUSION

We conclude that acute respiratory morbidity in moderately preterm infants is common and predicted by multiparity, caesarean section, low Apgar score and male sex.

Magnesium sulphate for women at term for neuroprotection of the fetus

BACKGROUND

Magnesium sulphate is extensively used in obstetrics for the treatment and prevention of eclampsia. A recent meta-analysis has shown that magnesium sulphate is an effective fetal neuroprotective agent when given antenatally to women at risk of very preterm birth. Term infants account for more than half of all cases of cerebral palsy, and the incidence has remained fairly constant. It is important to assess if antenatal administration of magnesium sulphate to women at term protects the fetus from brain injury, and associated neurosensory disabilities including cerebral palsy.

OBJECTIVES

To assess the effectiveness of magnesium sulphate given to women at term as a neuroprotective agent for the fetus.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trial Register (31 July 2012) and the reference lists of other Cochrane reviews assessing magnesium sulphate in pregnancy.

SELECTION CRITERIA

Randomised controlled trials comparing antenatally administered magnesium sulphate to women at term with placebo, no treatment or a different fetal neuroprotective agent. We also planned to include cluster-randomised trials, and exclude cross-over trials and quasi-randomised trials. We planned to exclude studies reported as abstracts only.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for eligibility and for risk of bias. Two authors independently extracted data. Data were checked for accuracy.

MAIN RESULTS

We included one trial (involving 135 women with mild pre-eclampsia at term). An additional six studies are awaiting further assessment.The included trial compared magnesium sulphate with a placebo and was at a low risk of bias. The trial did not report any of this review's prespecified primary outcomes. There was no significant difference between magnesium sulphate and placebo in Apgar score less than seven at five minutes (risk ratio (RR) 0.51; 95% confidence interval (CI) 0.05 to 5.46; 135 infants), nor gestational age at birth (mean difference (MD) -0.20 weeks; 95% CI -0.62 to 0.22; 135 infants).There were significantly more maternal side effects (feeling warm and flushed) in the magnesium sulphate group than in the placebo group (RR 3.81; 95% CI 2.22 to 6.53; 135 women). However, no significant difference in adverse effects severe enough to cease treatment was observed (RR 3.04; 95% CI 0.13 to 73.42; 135 women). There were no significant differences seen between groups in the rates of postpartum haemorrhage (RR 4.06; 95% CI 0.47 to 35.38; 135 women) and caesarean section (RR 0.80; 95% CI 0.39 to 1.63; 135 women).

AUTHORS' CONCLUSIONS

There is currently insufficient evidence to assess the efficacy and safety of magnesium sulphate when administered to women for neuroprotection of the term fetus. As there has been recent evidence for the use of magnesium sulphate for neuroprotection of the preterm fetus, high-quality randomised controlled trials are needed to determine the safety profile and neurological outcomes for the term fetus. Strategies to reduce maternal side effects during treatment also require evaluation.

The expression profile of microRNAs in wistar rats with lipopolysaccharide-induced periventricular leukomalacia

Over the recent decades, with numbers of premature infants being cured, clinical diseases on brain damage like periventricular leukomalacia (PVL) have become much more common. Meanwhile, since the discovery of first miRNA lin-4, an increasing number of important studies about this small RNA have been performed not only in the normal organ development but also in the pathogenic mechanism of diseases. However, throughout the past several years, there have been rare miRNA researches discussing the connection between the PVL and miRNA. In view of this situation, we constructed an animal model of PVL induced by lipopolysaccharide (LPS) and performed a miRNA microarray which was repeated three times to profile the expression of microRNAs (miRNAs) between two groups (PVL group versus control group). Then, miRNAs with notable fold changes (fold change >1.5) were found; some of them were further validated by real-time PCR. As a result, 104 differentially expressed miRNAs were identified using the microarray, including 64 upregulated and 40 downregulated miRNAs. Then, five miRNAs of them were selected, characterized by consistent trend in expression in all three microarrays. Among these five miRNAs (miRNA-451, miRNA-200b, miRNA-29a, miRNA-21, and miRNA-138), we subsequently selected miRNA-451 and miRNA-200b for real-time PCR because they possess the highest fold changes. Finally, the results of PCR are basically in accord with the microarray. We guess these new identified miRNAs may play an important role in the pathogenesis of PVL and may provide certain pathophysiological basis for the future research of related diseases in preterm infants.

TLR-4-dependent and -independent mechanisms of fetal brain injury in the setting of preterm birth

In this study, we sought to assess how essential activation of toll-like receptor 4 (TLR-4) is to fetal brain injury from intrauterine inflammation. Both wild-type and TLR-4 mutant fetal central nervous system cells were exposed to inflammation using lipopolysaccharide in vivo or in vitro. Inflammation could not induce neuronal injury in the absence of glial cells, in either wild-type or TLR-4 mutant neurons. However, injured neurons could induce injury in other neurons regardless of TLR-4 competency. Our results indicate that initiation of neuronal injury is a TLR-4-dependent event, while propagation is a TLR-4-independent event.

Postnatal administration of IL-1Ra exerts neuroprotective effects following perinatal inflammation and/or hypoxic-ischemic injuries

New therapeutic strategies are needed to protect neonates, especially premature newborns, against brain injury and associated neurobehavioral deficits. The role of pro-inflammatory cytokines, especially IL-1β, in the pathophysiological pathway leading to neonatal brain damage is increasingly recognized and represents an attractive therapeutic target. We investigated the therapeutic potential of postnatal systemic administration of the interleukin (IL)-1 receptor antagonist (IL-1Ra) in an animal model of perinatal brain injury using the insults most common to human neonates, i.e. prenatal exposure to inflammation and/or postnatal hypoxia-ischaemia (HI). We found that postnatal administration of IL-1Ra preserved motor function and exploratory behavior after either prenatal exposure to inflammatory agent lipopolysaccharide (LPS) or postnatal HI insult. The deleterious effect of combined prenatal LPS and postnatal HI on brain development was also alleviated by administration of IL-1Ra, as seen by the protected neural stem cell population, prevention of myelin loss in the internal capsule, decreased gliosis, and decreased neurobehavioral impairment. This study showed the distinct pattern of functional deficits induced by prenatal inflammation as compared to postnatal HI and the therapeutic potential of IL-1Ra administration against neonatal brain injury. Furthermore, our results highlight the potential for postnatal treatment of prenatal inflammatory stressors.

Early detection of placental inflammation by MRI enabling protection by clinically relevant IL-1Ra administration

OBJECTIVE

We studied whether magnetic resonance imaging (MRI) could be used to detect placental inflammation before the detection of irreversible tissue damage. Next, we tested whether this early detection would enable the administration of treatment (ie, interleukin-1 receptor antagonist [IL-1Ra]) in a realistic clinical time after diagnosis.

STUDY DESIGN

Pregnant rats were injected intraperitoneally with lipopolysaccharide with/without delayed IL-1Ra. MRI was performed at different time after the injection, and placentas were collected for comparison. Placental inflammation was assessed by determination of the levels of inflammatory cytokines.

RESULTS

Placental inflammation was detected by MRI as early as 3 hours after maternal administration of lipopolysaccharide, concomitantly to IL-1β up-regulation. This was observed before any tissue damage, which appeared only at 24 hours after the administration of lipopolysaccharide. Delayed IL-1Ra administration (after MRI diagnosis) protected the placenta, as seen by the preserved tissue integrity and limited macrophages infiltration in the placental parenchyma.

CONCLUSION

These findings established a noninvasive diagnostic method for early in utero detection of placental inflammation that would allow the administration of placentoprotective intervention within a clinically relevant delay after diagnosis.

Intrauterine inflammation, insufficient to induce parturition, still evokes fetal and neonatal brain injury

Exposure to prenatal inflammation is a known risk factor for long term neurobehavioral disorders including cerebral palsy, schizophrenia, and autism. Models of systemic inflammation during pregnancy have demonstrated an association with an immune response an adverse neurobehavioral outcomes for the exposed fetus. Yet, the most common route for an inflammatory exposure to a fetus is from intrauterine inflammation as occurs with chorioamnionitis. The aims of this study were to assess the effect of intrauterine inflammation on fetal and neonatal brain development and to determine if the gestational age of exposure altered the maternal or fetal response to inflammation. CD-1 timed pregnant mice on embryonic day 15 (E15) and E18.5 were utilized for this study. Dams were randomized to receive intrauterine infusion of lipopolysaccharide (LPS, 50 μg/dam) or normal saline. Different experimental groups were used to assess both acute and long-term outcomes. For each gestational age and each treatment group, fetal brains, amniotic fluid, maternal serum and placentas were collected 6h after intrauterine infusion. Rates of preterm birth, maternal morbidity and litter size were assessed. IL6 levels were assayed in maternal serum and amniotic fluid. An immune response was determined in the fetal brains and placentas by QPCR. Cortical cultures were performed to assess for fetal neuronal injury. Gene expression changes in postnatal day 7 brains from exposed and unexposed pups were determined. In the preterm period, low dose LPS resulted in a 30% preterm birth rate. Litter sizes were not different between the groups at either gestational age. IL6 levels were not significantly increased in maternal serum at either gestational time period. Low dose LPS increased IL6 levels in the amniotic fluid from exposed dams in the term but not preterm period. Regardless of gestational age of exposure, low dose intrauterine LPS activated an immune response in the placenta and fetal brain. Exposure to intrauterine LPS significantly decreased dendritic counts in cortical cultures from both the preterm and term period. Exposure to intrauterine inflammation altered gene expression patterns in the postnatal brain; this effect was dependent on gestational age of exposure. In conclusion, intrauterine inflammation, even in the absence of preterm parturition, can evoke fetal brain injury as evidence by alterations in cytokine expression and neuronal injury. Despite an absent or limited maternal immune response in low dose intrauterine inflammation, the immune system in the placenta is activated which is likely sufficient to induce a fetal immune response and subsequent brain injury. Changes in the fetal brain lead to changes in gene expression patterns into the neonatal period. Subclinical intrauterine inflammation can lead to fetal brain injury and is likely to be mechanistically associated with long term adverse outcomes for exposed offspring.

Homing of placenta-derived mesenchymal stem cells after perinatal intracerebral transplantation in a rat model

OBJECTIVE

The aim of this study is to assess early homing of placenta-derived stem cells after perinatal intracerebral transplantation in rats.

STUDY DESIGN

Neonatal Wistar rats (2-4 days old) were anesthetized, and 250,000 human placenta-derived mesenchymal stem cells (MSC) injected into the lateral ventricle or the paraventricular white matter using a stereotactic frame. Donor MSC were detected by immunohistochemistry using an antihuman HLA-ABC antibody.

RESULTS

In all, 84% of the animals survived the transplantation. Donor cells were detected in the brain ventricle 1-2 hours posttransplantation. After 4 hours, donor cells migrated throughout the ventricular system. At 1-4 weeks after transplantation, some cells had migrated into the periventricular white matter.

CONCLUSION

Human placenta-derived MSC were successfully transplanted into the lateral ventricles of neonatal rats. Donor cells survived, homed, and migrated in the recipient brains. Proliferation and differentiation analysis and functional tests will assess the therapeutic effects of stem cell transplantation.

The hospitalization assistance policy system in Japan

In Japan, the hospitalization assistance policy (HAP) system helps pregnant women who, for financial reasons, cannot give birth at medical institutions. The HAP system allows these women to deliver at specified midwifery institutions. We compared women with singleton pregnancies who gave birth with the HAP system (n=150) or without (control; n=2,869) . Although the percentage of women younger than 20 years was significantly greater in the HAP system group than in the control group, the parity number in the HAP system group was significantly greater than that in the control group. The percentage of non-Japanese was significantly higher in the HAP system group than in the control. The rates of preterm delivery and of low birth weight (<2,000 g) were significantly greater in the HAP system group than in the control group. From the perspective of perinatal medicine, social risks, such as poverty, present some perinatal problems, even in Japan.

Impact of chorioamnionitis on exhaled nitric oxide and endotracheal aspirate levels of nitrites-nitrates and interleukin-8 in mechanically ventilated preterm neonates

OBJECTIVES

To assess the influence of maternal chorioamnionitis on early exhaled nitric oxide (NO) and levels of nitrites-nitrates and interleukin (IL)-8 in endotracheal aspirate fluid in mechanically ventilated preterm neonates.

STUDY DESIGN

Cross-sectional study. PATIENT-SUBJECT SELECTION: Between September 2007 and August 2009, 54 mechanically ventilated preterm neonates were included. Patients were divided into two groups according to the presence or absence of maternal chorioamnionitis, and those without chorioamnionitis (controls) were further stratified into two subgroups by birth weight < or ≥ 2,000 g.

METHODOLOGY

The ventilator used was a Babylog 8000. The NO level assessed was the plateau value given by the software of the Sievers NOA apparatus. Collection of endotracheal aspirate fluid samples was performed coinciding with routine aspirations and using the dry technique.

RESULTS

The two groups of control neonates showed statistically significant differences in exhaled NO expressed as nl/min and normalized exhaled NO expressed as either nl/min or nl/min/kg, so they are not homogeneous and cannot be used in clinical practice. Serum C-reactive protein and endotracheal aspirate levels of nitrites-nitrates were significantly higher in the chorioamnionitis group than in controls (3.6 vs. 1.07 µmol/L; P = 0.035). Nitrites-nitrates levels were positively correlated with exhaled NO in ppb (ρ = 0.367; P = 0.006). Minute exhaled endogenous NO was significantly higher in the chorioamnionitis group (0.48 vs. 0.27 nl/min/kg; P = 0.021).

CONCLUSIONS

In mechanically ventilated preterm infants weighing <2,000 g, maternal chorioamnionitis was associated with an increase of early exhaled NO (nl/min/kg) and serum levels of C-reactive protein and levels of nitrites-nitrates in endotracheal aspirate fluid.

Developmental regulation of the neuroinflammatory responses to LPS and/or hypoxia-ischemia between preterm and term neonates: An experimental study

Background

Preterm and term newborns are at high risk of brain damage as well as subsequent cerebral palsy and learning disabilities. Indeed, hypoxia-ischemia (HI), pathogen exposures, and associated intracerebral increase of pro-inflammatory cytokines have all been linked to perinatal brain damage. However, the developmental effects of potential variations of pro- and anti-inflammatory cytokine ratios remain unknown.

Methods

Using rat models of perinatal brain damage induced by exposures to lipopolysaccharide (LPS) and/or HI at distinct levels of maturity, we compared cytokine expression at stages of cerebral development equivalent to either preterm (postnatal day 1, P1) or term (P12) newborns.

Results

At P1, expression of anti-inflammatory cytokine within the brain was either not modulated (IL-6, IL-10) or down-regulated (IL-1ra, TGF-β1) by HI, LPS or LPS+HI. In contrast, there was at P12 an up-regulation of all anti-inflammatory cytokines studied in HI or LPS+HI condition, but not after LPS exposure. Interestingly, IL-1β was the main pro-inflammatory cytokine up-regulated moderately at P1, and strongly at P12, with a weak co-expression of TNF-α observed mainly at P12. These age-dependant inflammatory reactions were also accompanied, under HI and LPS+HI conditions, at P12 only, by combined: (i) expression of chemokines CINC-1 and MCP-1, (ii) blood-brain barrier (BBB) leakage, and (iii) intracerebral recruitment of systemic immune cells such as neutrophils. In contrast, sole LPS induced IL-1β responses mainly within white matter at P1 and mainly within gray matter at P12, that were only associated with early MCP-1 (but no CINC-1) induction at both ages, without any recruitment of neutrophils and CD68+ cells.

Conclusion

HI and LPS+HI induce pro-inflammatory oriented immune responses in both preterm and term like brains, with a maximal inflammatory response triggered by the combination of LPS+HI. The profile of these neuroinflammatory responses presented striking variations according to age: no or down-regulated anti-inflammatory responses associated with mainly IL-1β release in preterm-like brains (P1), in sharp contrast to term-like brains (P12) presenting stronger anti-and pro-inflammatory responses, including both IL-1β and TNF-α releases, and BBB leakage. These developmental-dependant variations of neuroinflammatory response could contribute to the differential pattern of brain lesions observed across gestational ages in humans. This also highlights the necessity to take into consideration the maturation stage, of both brain and immune systems, in order to develop new anti-inflammatory neuroprotective strategies.

Umbilical cord blood cell transplantation after brain ischemia--from recovery of function to cellular mechanisms

Cell transplantation has been proposed as a potential approach to the treatment of neurological disorders. One cell population of interest consists of human umbilical cord blood (hUCB) cells, which have previously been shown to be useful for reparative medicine in haematological diseases. However, hUCB cells are also capable of differentiating into various non-haematopoietic cells, including those of the neural lineage. Moreover, hUCB cells can secrete numerous neurotrophic factors and modulate immune function and inflammatory reaction. Several studies on animal models of ischemic brain injury have demonstrated the potential of hUCB cells to minimize damage and promote recovery after ischemic brain injury.This review focuses on the treatment of both stroke and perinatal hypoxic-ischemic brain injury using hUCB cells. We discuss the therapeutic effects demonstrated after hUCB cell transplantation and emphasize possible mechanisms counteracting pathophysiological events of ischemia, thus leading to the generation of a regenerative environment that allows neural plasticity and functional recovery. The therapeutic functional effects of hUCB cells observed in animal models make the transplantation of hUCB cells a promising experimental approach in the treatment of ischemic brain injury. Together with its availability, low risk of transplantation, immaturity of cells, and simple route of application, hUCB transplantation may stand a good chance of being translated into a clinical setting for the therapy of ischemic brain injury.

The impact of clinical maternal chorioamnionitis on neurological and psychological sequelae in very-low-birth weight infants: a case-control study

AIMS

To assess the relationship between clinically maternal chorioamnionitis and outcome in preterm very-low-birth weight (VLBW) infants.

METHODS

An observational case-control study was conducted in the neonatology departments of 12 acute care teaching hospitals in Spain. Between January 2004 and December 2006, all consecutive VLBW (≤1500 g) infants who were born to a mother with clinical chorioamnionitis were enrolled. The controls included infants who were born to mothers without chorioamnionitis, matched by gestational age, and immediately born after each index case. At a corrected age of 24 months, a neurological examination and a psychological assessment of the surviving children were performed.

RESULTS

Sixty-six of the newborn infants died; therefore, 262 infants from the original sample were available for the study. Follow-up data were obtained at a corrected age of 24 months from a total of 209 children (106 cases and 103 controls, 80% of the original sample size). Seventy children (33.5%) were diagnosed with some type of sequelae. The following conditions were all more prevalent in infants born to mothers with chorioamnionitis in comparison to controls: low development quotient (98.3±12.15 vs. 95.9±15.64; P=0.497), cerebral palsy (4.9% vs. 10.4%; P=0.138), seizures (1.0% vs. 3.8%; P=0.369), and other neurological or sensorial sequelae (32.0% vs. 34.9%; P=0.611).

CONCLUSIONS

After controlling for gestational age, the study population demonstrated that the neurological outcomes in infants at a corrected age of 24 months was not worsened by chorioamnionitis.

Oxidative stress and antioxidant strategies in newborns

Oxidative stress (OS) is defined as an unbalance between prooxidant and antioxidant factors that can lead to cellular and tissue damage.The newborn, especially if preterm, is highly prone to OS and to the toxic effect of free radicals (FR). At birth, the newborn is exposed to a relatively hyperoxic environment caused by an increased oxygen bioavailability with greatly enhanced generation of FR. Additional sources (inflammation, hypoxia, ischemia, glutamate, and free iron release) occur magnifying OS. In the preterm baby, the perinatal transition is accompanied by the immaturity of the antioxidant systems and the reduced ability to induce efficient homeostatic mechanisms designed to control overproduction of cell-damaging FR. Improved understanding of the pathophysiological mechanism involved in perinatal brain lesions helps to identify potential targets for neuroprotective interventions, and the knowledge of these mechanisms has enabled scientists to develop new therapeutic strategies that have confirmed their neuroprotective effects in animal studies. Considering the growing role of OS in preterm newborn morbidity in respect to the higher risk of FR damage in these babies, a strict control of oxygen administration, lutein, melatonin, and hypothermia show great promise as potential neuroprotectants. This review provides an overview of the pathogenesis of free radical-mediated diseases of the newborn and the antioxidant strategies for now tested to reduce the OS and its damaging effects.

Proinflammatory orientation of the interleukin 1 system and downstream induction of matrix metalloproteinase 9 in the pathophysiology of human perinatal white matter damage

A preclinical model showed a direct role of the interleukin 1 (IL-1) system in the pathogenesis of perinatal brain damage, but evidence linking these findings to human white matter damage (WMD) requires confirmation in human cases. We analyzed the IL-1β system using immunohistochemistry to characterize the expression of IL-1 receptors (IL-1R1 and IL-1R2), IL-1R antagonist (IL-1Ra), and induction of downstream effectors in 9 human brains with WMD. Interleukin 1β overexpression was associated with IL-1R1 and IL-1R2 immunoreactivity in areas with WMD; immunolabeling for both was detected on astrocytes and microglia/macrophages. There was no immunoreactivity for these receptors in nondamaged white matter in the same brains. Interleukin-1Ra expression was significantly less upregulated than that of IL-1β. This IL-1β/IL-1Ra imbalance was particularly pronounced in the brains of very preterm versus near-term infants. We additionally found overexpression of matrix metalloproteinase 9 (MMP-9) in WMD areas. The MMP-9 colocalized with IL-1β in microglia/macrophages in affected cerebral areas. These data indicate that there is activation and proinflammatory orientation of the IL-1 system with downstream induction of MMP-9 in perinatal WMD. Because both of these mediators are known to be involved in neural cell injury, we infer that IL-1 pathway activation has a deleterious role in the pathophysiology of WMD in human neonates.

Clinical significance of singleton pregnancies complicated by placental abruption associated with histological chorioamnionitis

The aim of this study was to determine the perinatal outcomes of placental abruption associated with the presence of histological chorioamnionitis. We reviewed the obstetric records of 96 singleton deliveries complicated by placental abruption after 22 weeks' gestation. Of these 96 cases, 37 cases (39%) were diagnosed as having histological chorioamnionitis in the placenta. The incidence of premature delivery, preterm rupture of the membranes and low birth weight in the cases of placental abruption with chorioamnionitis were higher than in cases without chorioamnionitis. However, there were no significant differences in the incidence of other outcomes, such as fetal demise, low Apgar score, or low umbilical artery pH, between the cases of placental abruption with and without histological chorioamnionitis. Although the incidence of prematurity in the cases of placental abruption with chorioamnionitis was higher than that in cases without chorioamnionitis, there were no significant differences in fetal and neonatal conditions between the abruption cases with and without chorioamnionitis.

Progress toward improved understanding of infection-related preterm birth

Current strategies to prevent infection-related preterm birth and its associated neonatal morbidities have had limited success. Improved understanding of the pathogen-host interactions underlying altered colonization of the lower genital tract is necessary before significant progress can be made. The application of novel diagnostic techniques such as broad range PCR and proteomic analysis contribute to our knowledge of the diversity and abundance of microbial species invading the amniotic cavity as well as the resultant inflammatory response. Preterm infants delivered following intrauterine infection may respond differently to subsequent infectious challenges in the neonatal intensive care unit.

Interpretation of amniotic fluid white blood cell count in "bloody tap" amniocenteses in women with symptoms of preterm labor

OBJECTIVE

To estimate whether blood-contaminated amniotic fluid affects the performance of white blood cell (WBC) count in diagnosing intraamniotic inflammation and infection.

METHODS

Three hundred fifty-seven consecutive women pregnant with singletons undergoing amniocentesis to rule out infection were enrolled prospectively. A "bloody tap" was defined as a red blood cell (RBC) count of 1,000 cells/mm or more. Proteomics analysis of amniotic fluid was used in this study as the standard for diagnosing inflammation. Infection was confirmed by positive amniotic fluid culture. An amniotic fluid WBC count correction formula was computed using maternal WBC count, hematocrit, and mean corpuscular volume.

RESULTS

The prevalence of a bloody tap amniocentesis was 22% (77 of 357). In the absence of inflammation, the amniotic fluid WBC count was significantly higher in bloody tap (median [interquartile range] 18 [9-58] cells/mm) compared with non-bloody tap specimens (4 [1-10] cells/mm; P<.001). The correction formula reversed this difference to a nonsignificant level (bloody tap 0 [0-17] compared with non-bloody tap 3 [1-10] cells/mm; P=.273). In the setting of inflammation, the observed WBC count of bloody tap samples (778 [197-2,062 cells/mm]) was significantly elevated compared with that of the non-bloody tap specimens (616 [105-1,730] cells/mm; P=.023). Correction of the WBC count in bloody tap amniocenteses improved the test accuracy and positive likelihood ratios for inflammation and infection. A correction algorithm was not useful in amniotic fluid specimens with less than 1,000/RBCs/mm or WBC counts more than 1,100 cells/mm. Given the nonlinear relationship between amniotic fluid WBC and RBC, for a rapid correction of WBC count, the number of neutrophils that need to be subtracted from the observed WBC count is variable.

CONCLUSION

In the setting of an amniotic fluid sample contaminated with 1,000 RBCs/mm or more, WBC count is a less accurate indicator of inflammation and infection. In such samples, correction of WBC count enhances diagnostic performance for inflammation and infection.

LEVEL OF EVIDENCE

II.

The number of CD68(+) (Hofbauer) cells is decreased in placentas with chorioamnionitis and with advancing gestational age

Hofbauer cells are placental macrophages found in chorionic villous stroma; they express classic monocyte/macrophage markers, such as CD68. Little is known about their participation in placental disease and immunologic interactions at the placental interface. The aim of this study was to quantify the amount of Hofbauer cells in placentas complicated, or not, by chorioamnionitis and in placentas from different gestational ages. Fifty-eight 2nd- and 3rd-trimester placentas with the histologic diagnosis of acute chorioamnionitis were compared with 42 control placentas matched according to gestational age. Immunohistochemistry evaluation was performed with a monoclonal anti-CD68 antibody. Five areas of each placenta were photographed and 5 investigators, with the help of a computerized image analysis program, independently evaluated the number of CD68(+) cells. Our results showed that there are significantly fewer CD68(+) cells per villous area in placentas diagnosed with chorioamnionitis than in those of controls (P < 0.001). Moreover, there was a significant overall decrease in the number of these cells in 3rd as compared with 2nd trimester placentas (P  =  0.02), as well as in placentas from term as compared to preterm pregnancies (P  =  0.004). Our data indicate that CD68(+) Hofbauer cells may be involved in placental infection and possibly associated with the developmental maturation of the fetoplacental unit.

Tei index to assess fetal cardiac performance in fetuses at risk for fetal inflammatory response syndrome

OBJECTIVES

To examine, in patients with premature rupture of the amniotic membranes (PROM) at < 34 weeks of gestation, the relationship between fetal myocardial performance measured by the Tei index and fetal inflammatory response syndrome (FIRS).

METHODS

A case-control study was conducted including 15 preterm PROM patients with gestational age between 24 and 33 weeks admitted to Hospital de Clínicas de Porto Alegre, and 15 controls with the same gestational age range. Fetal echocardiography with Doppler was performed at admission for the preterm PROM group, with serial examinations every 7-10 days thereafter until delivery, and at the time of inclusion in the control group. Flow velocity waveforms were obtained for the left ventricle, from which the Tei index was calculated. Placental histopathology and perinatal outcome were compared between the groups.

RESULTS

The left ventricular Tei index was significantly greater in fetuses with preterm PROM compared with controls (0.63 +/- 0.13 vs. 0.51 +/- 0.10, P = 0.007). While there was no difference in isovolumetric times, the left ventricular ejection time was significantly shorter in the preterm PROM group (164 +/- 17 ms vs. 184 +/- 16 ms, P = 0.003). In the preterm PROM group, neonatal sepsis was diagnosed in 73.3%, and funisitis and chorionic vasculitis confirmed FIRS in 53.3%, compared with 6.7% for these three diagnoses in controls (P = 0.001).

CONCLUSIONS

These data provide further evidence that cardiac dysfunction is present in the setting of preterm PROM. The study of myocardial performance with the Tei index is a novel non-invasive approach to assess cardiac function and monitor the fetus affected with FIRS.

Loss of cation-chloride cotransporter expression in preterm infants with white matter lesions: implications for the pathogenesis of epilepsy

Epilepsy associated with preterm birth is often refractory to anticonvulsants. Children who are born preterm are also prone to cognitive delay and behavioral problems. Brains from these children often show diffuse abnormalities in cerebral circuitry that is likely caused by disrupted development during critical stages of cortical formation. To test the hypothesis that prenatal injury impairs the developmental switch of gamma-amino butyric acid (GABA)ergic synapses from excitatory to inhibitory, thereby disrupting cortical circuit formation and predisposing to epilepsy, we used immunohistochemistry to compare the expression of cation-chloride transporters that developmentally regulate postsynaptic GABAergic discharges in postmortem cerebral samples from infants born preterm with known white matter injury (n = 11) with that of controls with minimal white matter gliosis (n = 7). Controls showed the expected developmental expression of cation-chloride transporters NKCC1 and KCC2 and ofcalretinin, a marker of a GABAergic neuronal subpopulation. Samples from infants with white matter damage showed a significant loss of expression of both NKCC1 and KCC2 in subplate and white matter. By contrast, there were no significant differences in total cell number or glutamate transporter VGLUT1 expression. Together, these novel findings suggest a molecular mechanism involved in the disruption of a critical stage of cerebral circuit development after brain injury from preterm birth that may predispose to epilepsy.

Effect of maternal clinical chorioamnionitis on neonatal morbidity in very-low birthweight infants: a case-control study

AIMS

To assess the relationship between maternal clinical chorioamnionitis and neonatal outcome in preterm very-low birthweight (VLBW) infants.

METHODS

An observational case-control study was conducted in the Neonatology Services of 12 acute-care teaching hospitals in Spain. Between January 2004 and December 2006, all consecutive VLBW (< or =1500 g) infants born to a mother with clinical chorioamnionitis were enrolled. Controls were infants without chorioamnionitis matched by gestational age who were born immediately after each index case.

RESULTS

There were 165 cases and 163 controls. A significantly higher percentage of cases than controls required intubation (53% vs. 35.8%), had normal intrauterine growth (98.1% vs. 84.7%), were born in a tertiary center (inborn) (95.1% vs. 89.1%), from single gestations (76.4% vs. 65.6%) and vaginal delivery (47.3% vs. 33.3%), showed a lower Apgar score at 5 min, and presented a higher rate of early-onset sepsis (10.4% vs. 1.2%). Older maternal age (32.5 vs. 30.8 years), premature labor (67.3% vs. 25.8%), premature rupture of membranes (61.3% vs. 25.8%), and antibiotic treatment (88.5% vs. 52.3%) were significantly more frequent among cases than controls.

CONCLUSIONS

After controlling by gestational age, maternal chorioamnionitis was associated with neonatal depression and early sepsis but not with other prematurity-related complications.

The role of fetal autopsy and placental examination in the causes of fetal death: a retrospective study of 132 cases of stillbirths

PURPOSE

To investigate the most plausible cause of stillbirth by evaluating clinical records and postmortem examination findings including placental analysis.

METHODS

A retrospective cohort study concerning 132 stillbirths from 124 pregnancies occurred in the Mother-Infant Department of the University Hospital of Modena, Italy, from January 2000 to December 2004. Collected data were reviewed and classified according to the Gardosi ReCoDe system.

RESULTS

A reasonable cause of fetal death was identified in 99/124 pregnancies (79.84%). No associated relevant factors were disclosed in 25 fetuses (20.16%) classified as unexplained stillbirths. A succeeding scrupulous analysis of the placenta and an accurate clinical record review were useful to detect other conditions in 82 cases, including 5 cases of unexplained stillbirth. The major relevant conditions associated to stillbirths were feto-placental infection especially in the early fetal gestation age, under the 24th week of gestation, and placental insufficiency occurred both in early and late gestation age fetuses and mainly associated with a IUGR (<10th customized percentile). The main frequent secondary conditions were represented by placental anomalies including cluster of avascular villi with stromal fibrosis associated to thrombosis in minor and/or major vessel(s). Through the further analysis of the placenta, we were able to reduce the unexplained stillbirth rate from 20.16 to 15%.

CONCLUSION

Accurate fetal autopsy and placental examination related to meticulous clinical collecting data are requisites in the valuation of stillbirth and could play an important role in reduction of unexplained stillbirth rate.

Clearance of apoptotic neutrophils is diminished in cord blood monocytes and does not lead to reduced IL-8 production

Phagocytosis of apoptotic cells, e.g., neutrophils, by monocytes is essential for resolution of inflammation. Delayed removal leads to secondary necrosis, perpetuating inflammation, and tissue destruction. Common histologic features in neonatal chronic inflammatory disorders are an accumulation of apoptotic cells in inflamed tissues. We hypothesized that apoptotic cell removal by monocytes is compromised in newborns. PKH-26 labeled autologous or allogeneic apoptotic neutrophils were fed to monocytes of adult donors (PBMO) and cord blood (CBMO), and phagocytic activity was analyzed by flow cytometry and confocal microscopy. Relative mRNA-expression levels of 21 surface receptors and bridging molecules relevant for apoptotic cell removal were measured, as was postphagocytic IL-8 production upon LPS-stimulation. Compared with PBMO, CBMO exhibited a significantly diminished phagocytotic competence for autologous and allogeneic apoptotic neutrophils. mRNA-expression levels of milk fat globule-EGF factor 8 and T cell immunoglobulin- and mucin-domain-containing molecule, two crucial members of the phagocytic synapse of apoptotic cell removal, were reduced in CBMO. In PBMO, interaction with autologous apoptotic neutrophils reduced LPS-induced IL-8 production whereas it was enhanced in CBMO. Our data suggest a specific defect in CBMO during clearance of apoptotic neutrophils resulting in impaired anti-inflammatory capacity.

Subclinical histologic chorioamnionitis and related clinical and laboratory parameters in preterm deliveries

BACKGROUND

Histologic chorioamnionitis (HCA) is associated with preterm delivery and with neonatal morbidity and mortality. Because HCA is usually subclinical, histologic examination of the placenta is essential for confirmatory diagnosis. In the present study, the correlations between subclinical HCA and relevant clinical and laboratory parameters were analyzed.

METHODS

This was a retrospective study. We reviewed the placental histopathologic findings and the charts of patients who were admitted to our neonatal intensive care unit after delivery and their mothers between January 2007 and March 2008. A total of 77 preterm infants [gastational age (GA): 32.2 3.4 weeks, birth weight (BW): 1718 +/- 554 g] were categorized as group A with histologic evidence of placental inflammation (n=27) or group B without histologic evidence of placental inflammation (n=50). Placental histology was studied to identify the presence of inflammatory states such as chorioamnionitis, funisitis and deciduitis. Laboratory parameters including complete blood count, differential count, and C-reactive protein (CRP) level of mothers and initial arterial blood gas, glucose Level and mean blood pressure of the infants were documented. Gestational age, Apgar score, history of prolonged premature rupture of membrane (prolonged PROM), gestational diabetes mellitus, meconium-stained amniotic fluid, pregnancy-induced hypertension and signs of pre-eclampsia were also collected as clinical parameters. All data were analyzed using independent t tests and Fisher's exact test, as appropriate.

RESULTS

Group A newborns had a significantly lower gestational age (30.8 +/- 4.1 weeks vs. 33.0 +/- 2.6 weeks, p < 0.05) and higher CRP level (0.56 +/- 0.92 mg/dL vs. 0.12 +/- 0.14 mg/dL, p < 0.05), together with higher maternal WBC count (13,002 +/- 4344/microL vs. 10,850 +/- 3722/microL, p < 0.05) and higher rate of prolonged PROM [14/27 (51.85%) vs. 8/37 (21.62%), p < 0.05] compared with group B newborns.

CONCLUSION

We found that HCA was significantly correlated with lower gestational age, higher CRP level of preterm infants, higher maternal WBC count, and a higher rate of prolonged PROM. Our results demonstrate a significant association between HCA with an elevated CRP level in preterm infants. These findings further confirmed the association between maternal inflammation and preterm deliveries.

Phagocytosis and postphagocytic reaction of cord blood and adult blood monocyte after infection with green fluorescent protein-labeled Escherichia coli and group B Streptococci

BACKGROUND

Neonatal sepsis is characterized by an excessive inflammatory response induced by immune cells (monocytes). We investigated the initial stage of monocyte-pathogen interaction, i.e. bacterial ingestion and degradation at the single-cell level, by comparing a new flow cytometric procedure with culture methods. We also examined the hypothesis that, in terms of phagocytosis-induced cell death (PICD), phenotype, or cytokine production, cord blood monocytes (CBMO) differ from monocytes derived from adults (peripheral blood monocytes, PBMO).

METHODS

Phagocytosis and intracellular degradation were assessed by means of flow cytometry and bacterial cultures of green fluorescent protein-labeled group B Streptococci (GBS) and Escherichia coli. The production of reactive oxygen species (ROS) was measured through luminol-enhanced chemiluminescence. Apoptosis, phenotype, and cytokine production were assessed through flow cytometry.

RESULTS

Flow cytometry and bacterial cultures showed no difference between phagocytosis and degradation of GBS and E. coli by PBMO and CBMO. A high correlation between both methods was observed. No difference in ROS production was evident. In comparison with PBMO, CBMO apoptosis was lower after exposure to GBS and E. coli. Similarities were found between nonapoptotic monocytes and pro-inflammatory monocytes.

CONCLUSIONS

PICD is lower in CBMO during the early stages of monocyte-pathogen interaction. Our results emphasize that monocyte apoptosis has a potential role in tailoring the immune response in neonatal sepsis.

Adenosine deaminase activity, lipid peroxidation and astrocyte responses in the cerebral cortex of rats after neonatal hypoxia ischemia

Hypoxia ischemia (HI) is a common cause of damage in the fetal and neonatal brain. Lifelong disabilities such as cerebral palsy, epilepsy, behavioral and learning disorders are some of the consequences of brain injury acquired in the perinatal periods. Inflammation and formation of free radicals appear to play key roles in neonatal HI. The aim of this study was to describe the chronological sequence of adenosine deaminase (ADA) activity, the oxidative damage changes and astrocyte response using the classic model of neonatal HI. We observed an increase in the activity of ADA and lipid peroxidation in the cerebral cortex 8 days after neonatal HI. This was accompanied by a GFAP-positive, and the degree of brain damage was determined histochemically by hematoxylin-eosin (HE). Taking into account the important anti-inflammatory role of adenosine, ADA may provide an efficient means for scavenging cell-surrounding adenosine and play an important part in subsequent events of neonatal HI in association with GFAP reactive gliosis. The present investigation showed that neonatal HI causes the increase of free radicals and significant damage in the cerebral cortex. The increase in ADA activity may reflect the activation of the immune system caused by HI because the morphological analysis exhibited a lymphocytic infiltration.