Histological chorioamnionitis and the risk of early intraventricular hemorrhage in infants born < or =28 weeks gestation

The influence of chorioamnionitis on respiratory drive and spontaneous breathing of premature infants at birth: a narrative review

Most very premature infants breathe at birth but require respiratory support in order to stimulate and support their breathing. A significant proportion of premature infants are affected by chorioamnionitis, defined as an umbrella term for antenatal inflammation of the foetal membranes and umbilical vessels. Chorioamnionitis produces inflammatory mediators that potentially depress the respiratory drive generated in the brainstem. Such respiratory depression could maintain itself by delaying lung aeration, hampering respiratory support at birth and putting infants at risk of hypoxic injury. This inflammatory-mediated respiratory depression may contribute to an association between chorioamnionitis and increased requirement of neonatal resuscitation in premature infants at birth. This narrative review summarises mechanisms on how respiratory drive and spontaneous breathing could be influenced by chorioamnionitis and provides possible interventions to stimulate spontaneous breathing.  Conclusion: Chorioamnionitis could possibly depress respiratory drive and spontaneous breathing in premature infants at birth. Interventions to stimulate spontaneous breathing could therefore be valuable. What is Known: • A large proportion of premature infants are affected by chorioamnionitis, antenatal inflammation of the foetal membranes and umbilical vessels. What is New: • Premature infants affected by chorioamnionitis might be exposed to higher concentrations of respiratory drive inhibitors which could depress breathing at birth. • Premature infants affected by chorioamnionitis seem to be associated with a higher and more extensive requirement of resuscitation at birth.

Establishment and evaluation of nomogram for predicting intraventricular hemorrhage in neonatal acute respiratory distress syndrome

BACKGROUND

Intraventricular hemorrhage (IVH) is the most common type of brain injury in newborns, especially in newborns with Neonatal acute respiratory distress syndrome (ARDS). IVH can cause brain parenchyma damage and long-term neurological sequelae in children. Early identification and prevention of sequelae are essential. This study aims to establish a predictive nomogram for the early prediction of IVH in newborns with ARDS.

METHODS

From 2019 to 2021, we collected data from 222 infants diagnosed with ARDS in the Department of Neonatology, First Affiliated Hospital of Xinjiang Medical University. Infants have been randomly assigned to the training set (n = 161) or the validation set (n = 61) at a ratio of 7:3. Variables were screened using the Least Absolute Contract and Selection Operator (LASSO) regression to create a risk model for IVH in infants with ARDS. The variables chosen in the LASSO regression model were used to establish the prediction model using multivariate logistic regression analysis.

RESULTS

We recognized 4 variables as independent risk factors for IVH in newborns with ARDS via LASSO analysis, consisting of premature rupture of membranes (PROM), pulmonary surfactant (PS) dosage, PH¹ and Arterial partial pressure of oxygen (PaO₂¹). The C-Index for this dataset is 0.868 (95% CI: 0.837-0.940) and the C index in bootstrap verification is 0.852 respectively. The analysis of the decision curve shows that the model can significantly improve clinical efficiency in predicting IVH. We also provide a website based on the model and open it to users for free, so that the model can be better applied to clinical practice.

CONCLUSION

In conclusion, the nomogram based on 4 factors shows good identification, calibration and clinical practicability. Our nomographs can help clinicians make clinical decisions, screen high-risk ARDS newborns, and facilitate early identification and management of IVH patients.

Placental pathology and intraventricular hemorrhage in preterm and small for gestational age infants

OBJECTIVE

The aim of this study was to examine the relationship between chorioamnionitis and vascular malperfusion on placental pathology and intraventricular hemorrhage (IVH) in premature and small for gestational age (SGA) infants.

STUDY DESIGN

A retrospective analysis of 263 infants ≤34 weeks gestation or ≤1800 g and their mothers was conducted by chart review for placental pathology and clinical data from 2014 to 2018. Unadjusted and adjusted odds ratios (OR) for the association of placental pathology with IVH were calculated.

RESULT

Unadjusted OR showed an association between acute chorioamnionitis and IVH, but logistic regression analysis showed a non-significant adjusted OR between acute or chronic chorioamnionitis with IVH. Maternal vascular malperfusion was significantly associated with increased IVH when controlling for confounders.

CONCLUSION

Placental maternal vascular malperfusion is associated with the development of IVH in premature and SGA infants when controlling for other confounders.

Pathological staging of chorioamnionitis contributes to complications in preterm infants

Objective

To investigate the effect of pathological staging of chorioamnionitis (CA) on complications in preterm infants;

Methods

A single-center, retrospective study was conducted to choose singleton preterm infants (gestational age < 37 weeks) from the Department of Obstetrics and Gynecology in our hospital from December 2016 to December 2017. The basic data and placental pathological results were retrospectively collected. According to the placental pathological results of whether inflammation infiltrating amnion, CA 0/I phase was classified into non-amnionitis group, CA II/III phase was classified into amnionitis group, the incidence of common complications in preterm infants was compared. Further, logistic regression was used to analyze the effects of amnionitis on complications after being adjusted to gestational age, birth weight and thrombocytopenia.

Results

A total of 221 preterm infants were enrolled, including 186 cases in non-amnionitis group and 35 cases in amnionitis group. The gestational age of amnionitis group (32.00 ± 2.71 weeks) was significantly lower than non-amnionitis group (34.14 ± 2.06 weeks), birth weight (1.93 ± 0.64 kg) was significantly lower than that of non-amnionitis group (2.26 ± 0.58 kg), and the hospital stay in amnionitis group was significantly longer (25.71 ± 19.23 days), all of the difference above was statistically significant(P < 0.05). The incidence of intraventricular hemorrhage (IVH) in amnionitis group (37.14%) was significantly higher than that in non-amnionitis group (13.98%) (P = 0.002), and the risk of IVH was significantly increased by amnionitis (OR = 3.636, 95%CI: 1.632–8.102); after correction of gestational age, birth weight and thrombocytopenia, the risk of IVH was still significantly increased (OR = 2.471, P = 0.046, 95% CI: 1.015–6.015). And the late-onset IVH was more common (P = 0.009).

Conclusion

Amnionitis leads to a significant reduction in gestational age and birth weight in preterm infants, and it is an independent risk factor for IVH.

Antenatal infection and intraventricular hemorrhage in preterm infants: A meta-analysis

BACKGROUND

The aim of this study was to summarize current evidence evaluating the association between antenatal infection and intraventricular hemorrhage (IVH) in preterm infants.

MATERIALS AND METHODS

We searched for published articles on antenatal infection and IVH in 3 English (PubMed, the Cochrane Library, and EBSCO) and 3 Chinese (VEIPU, CNKI, and WANFANG) databases on May 19, 2019. In addition, the references of these articles were screened. The included studies had to meet all of the following criteria: preterm infants (<37 weeks); comparing antenatal infection with no infection; the outcomes included IVH (all grades), mild IVH, or sereve IVH; the type of study was randomized controlled trial or cohort study.

RESULTS

A total of 23 cohort studies involving 13,605 preterm infants met our inclusion criteria. Antenatal infection increased the risk of IVH (odds ratios ([OR] 2.18, 95% confidence intervals [CI] 1.58-2.99), mild IVH (OR 1.95, 95% CI 1.09-3.49) and severe IVH (OR 2.65, 95% CI 1.52-4.61). For type of antenatal infection, the ORs and 95% CI were as follows: 2.21 (1.60-3.05) for chorioamnionitis, 2.26 (1.55-3.28) for histologic chorioamnionitis, 1.88 (1.22-2.92) for clinical chorioamnionitis, and 1.88 (1.14-3.10) for ureaplasma.

CONCLUSIONS

Antenatal infection may increase the risk of developing IVH in the preterm infant. The evidence base is however of low quality and well-designed studies are needed.

[Epidemiology, risk factors and child prognosis: CNGOF Preterm Premature Rupture of Membranes Guidelines]

OBJECTIVES

To synthetize the available evidence regarding the incidence and risk factors of preterm premature rupture of membranes (PPROM). To describe the evolution of pregnancy, neonatal outcomes and the prognosis of infants born in a context of PPROM, according to the existence of an associated intrauterine infection and to the latency duration.

METHOD

Consultation of the Medline database, from 1980 to February 2018.

RESULTS

PPROM before 37 and before 34 weeks' gestation occur in 2-3% and <1% of pregnancies, respectively (LE2). Although many risk factors are identified, few are modifiable, and the vast majority of patients have no risk factors (LE2). Consequently, individual prediction of the risk of PPROM and primary prevention measures have not been shown to be effective and are not recommended in clinical practice (Grade B). Most women give birth within the week following PPROM (LE2). The main complications of PPROM are prematurity, intrauterine infection and obstetric and maternal complications (LE2). Latency duration and the frequency of complications decrease with increasing gestational age at PPROM (LE2). Neonatal prognosis is largely conditioned by gestational age at birth, with no apparent over-risk of poor outcomes linked to PPROM compared to other causes of preterm birth (LE2). In contrast, intrauterine infection is associated with an increased risk of in utero fetal death (LE3), necrotizing enterocolitis (LE1) and early-onset sepsis (LE2). The association of intrauterine infection with neurological morbidity remains controversial. Prolongation of latency, from gestational age at PPROM, is beneficial for the child (LE2).

CONCLUSION

PPROM is a major cause of prematurity and short- and long-term mortality and morbidity. Antenatal care is an important issue for obstetric and pediatric teams, aiming to reduce complications and adverse consequences for both mother and child.

Chorioamnionitis Is a Risk Factor for Intraventricular Hemorrhage in Preterm Infants: A Systematic Review and Meta-Analysis

Although chorioamnionitis (CA) is a well-known risk factor for white matter disease of prematurity, the association with intraventricular hemorrhage (IVH) is controversial and has not been yet systematically reviewed. We performed a systematic review and meta-analysis of studies exploring the association between CA and IVH. A comprehensive literature search was conducted using PubMed/MEDLINE and EMBASE, from their inception to 1 July 2017. Studies were included if they examined preterm infants and reported primary data that could be used to measure the association between exposure to CA and the presence of IVH. A random-effects model was used to calculate odds ratios (OR) and 95% confidence intervals (CI). We found 1,284 potentially relevant studies, of which 85 met the inclusion criteria (46,244 infants, 13,432 CA cases). Meta-analysis showed that CA exposure was significantly associated with all grades IVH (OR 1.88, 95% CI 1.61-2.19), with grades 1-2 IVH (OR 1.69, 95% CI 1.22-2.34), and with grades 3-4 IVH (OR 1.62, 95% CI 1.42-1.85). Both clinical and histological CA were associated with an increased risk for developing IVH in very preterm infants. In contrast, the presence of funisitis did not increase IVH risk when compared to CA in the absence of funisitis (OR 1.22, 95% CI 0.89-1.67). Further meta-analyses confirmed earlier findings that CA-exposed infants have significantly lower gestational age (GA; mean difference [MD] -1.20 weeks) and lower birth weight (BW; MD -55 g) than the infants not exposed to CA. However, meta-regression and subgroup analysis could not demonstrate an association between the lower GA and BW and the risk of IVH in the CA-exposed infants. In conclusion, our data show that CA is a risk factor for IVH, but also a risk factor for greater prematurity and more clinical instability. In contrast to other complications of prematurity, such as patent ductus arteriosus, retinopathy of prematurity, or bronchopulmonary dysplasia, the effect of CA on IVH appears to be independent of CA as causative factor for very preterm birth.

The combined exposure to intra-amniotic inflammation and neonatal respiratory distress syndrome increases the risk of intraventricular hemorrhage in preterm neonates

OBJECTIVE

To evaluate the impact of combined exposure to intra-amniotic inflammation and neonatal respiratory distress syndrome (RDS) on the development of intraventricular hemorrhage (IVH) in preterm neonates.

METHODS

This retrospective cohort study includes 207 consecutive preterm births (24.0-33.0 weeks of gestation). Intra-amniotic inflammation was defined as an amniotic fluid matrix metalloproteinase-8 concentration >23 ng/mL. According to McMenamin's classification, IVH was defined as grade II or higher when detected by neurosonography within the first weeks of life.

RESULTS

(1) IVH was diagnosed in 6.8% (14/207) of neonates in the study population; (2) IVH was frequent among newborns exposed to intra-amniotic inflammation when followed by postnatal RDS [33% (6/18)]. The frequency of IVH was 7% (8/115) among neonates exposed to either of these conditions - intra-amniotic inflammation or RDS - and 0% (0/64) among those who were not exposed to these conditions; and (3) Neonates exposed to intra-amniotic inflammation and postnatal RDS had a significantly higher risk of IVH than those with only intra-amniotic inflammation [odds ratio (OR) 4.6, 95% confidence interval (CI) 1.1-19.3] and those with RDS alone (OR 5.6, 95% CI 1.0-30.9), after adjusting for gestational age.

CONCLUSION

The combined exposure to intra-amniotic inflammation and postnatal RDS markedly increased the risk of IVH in preterm neonates.

Ante-, peri- and postnatal factors associated with intraventricular hemorrhage in very premature infants

BACKGROUND

Intraventricular hemorrhage (IVH) is one of the most serious complications in preterm infants and is associated with neurological sequelae and mortality. Over the past few decades, the rate of IVH has decreased due to improved neonatal intensive care. However, up to 15-25% of very and extremely premature infants (<32 and <28weeks of pregnancy (WOP) respectively) still suffer from IVH.

STUDY PURPOSE

The aim of this study was to perform an updated, multicenter analysis to identify ante-, peri, and postnatal factors other than gestational age/birth weight associated with IVH of any grade in a large cohort of very and extremely premature infants.

METHODS

We performed a retrospective analysis in a prospectively conducted multicenter cohort study between 01/01/1998-31/12/2012 at 5 level 3 perinatal centers. All relevant ante-, peri- and neonatal data were collected and univariate as well as multivariate logistic regression analysis was performed.

RESULTS

765 inborn infants with a gestational age<32 WOP were enrolled into this study (369 (48.2%) female; 396 (51.8%) male). Birth weight ranged from 315g to 2200g (mean 1149.7g, SD 371.9g); 279 (36.5%) were born ≤27+6 WOP and 486 (63.5%)≥28+0 WOP. IVH was seen in 177 (23.1%) patients. Multivariate analysis revealed that in addition to higher gestational age (OR 0.7, CI [0.6-0.8]), antenatal steroid treatment (OR 0.3, CI [0.2-0.6]) and caesarian section without uterine contraction (OR 0.6, CI [0.4-0.9]) were associated with a lower rate of IVH while RDS (OR 5.6, CI [1.3-24.2]), pneumothorax (OR 2.8, CI [1.4-5.5]) and use of catecholamines (OR 2.7, CI [1.7-4.5]) were associated with an increased risk of IVH. After exclusion of gestational age and birth weight from multivariate analysis, early onset sepsis (OR 1.6, CI [1.01-2.7]) and patent ductus arteriosus (OR 1.9, CI [1.1-3.1]) were associated with a higher rate of IVH. In addition, univariate analysis revealed that Apgar scores at 5min (p<0.001), BDP/ROP/NEC (p<0.001), mechanical ventilation (p<0.001) and inhalative nitric oxide (p<0.001) were significantly associated with IVH.

CONCLUSIONS

Our comprehensive analysis demonstrated that the occurrence of IVH in very premature infants is significantly associated with ante-, peri- and postnatal factors being either related to the degree of immaturity or indicating a critical clinical course after birth. The analysis reiterates the necessity for a very close cooperation between obstetricians and neonatologists to reduce the incidence of IVH in this susceptible cohort.

Time-to-event analysis of surgically treated posthemorrhagic hydrocephalus in preterm infants: a single-institution retrospective study

PURPOSE

The purpose of this study is to report time points relevant to the neurosurgical management of posthemorrhagic hydrocephalus (PHH).

METHODS

Data were collected retrospectively on 104 preterm infants with intraventricular hemorrhage (IVH) who received neurosurgical intervention for PHH at St. Louis Children's Hospital from 1994 to 2016. Kaplan-Meier curves were constructed for various endpoints.

RESULTS

IVH grade on head ultrasound obtained through routine clinical care was II, III, and IV in 5 (4.8%), 33 (31.7%), and 66 (63.5%) of the patients, respectively. Neither IVH size nor location appeared to affect development of PHH. Days from birth to IVH, ventriculomegaly, temporizing neurosurgical procedure (TNP), and permanent neurosurgical intervention were 2.0 (95% CI 1.7-2.3), 3.0 (2.5-3.5), 24.0 (22.2-25.8), and 101.0 (90.4-111.6), respectively. Grades III and IV IVH did not differ in age at IVH diagnosis (Χ ² (1 d.f.) = 1.32, p = 0.25), ventriculomegaly (Χ ² = 0.73, p = 0.40), TNP (Χ ² = 0.61, p = 0.43), or permanent intervention (Χ ² = 2.48, p = 0.17). Ventricular reservoirs and ventriculosubgaleal shunts were used in 71 (68.3%) and 30 (28.8%), respectively. Eighty (76.9%) of the patients ultimately received a VPS. Five (4.8%) underwent a primary endoscopic third ventriculostomy (ETV), and two (1.9%) had ETV for a revision procedure. Four of the seven ETVs had choroid plexus cauterization.

CONCLUSIONS

Although most infants who develop IVH and ventriculomegaly will do so within a few days of birth, at-risk infants should be observed for at least 4 weeks with serial head ultrasounds to monitor for PHH requiring surgery.

Revisiting the diagnostic criteria of clinical chorioamnionitis in preterm birth

OBJECTIVE

To re-evaluate the utility of the conventional criteria for clinical chorioamnionitis in the prediction of early-onset neonatal sepsis (EONS) in preterm birth.

DESIGN

Retrospective cohort study.

SETTING

Seoul, Republic of Korea.

SAMPLE

A total of 1468 singleton births between 24 and 34 weeks due to preterm labour (n = 713) or preterm prelabour rupture of membranes (n = 755).

METHOD

We evaluated three diagnostic categories of clinical chorioamnionitis: Criteria 1, conventional criteria; Criteria 2, combination of any three conventional parameters without prerequisite fever; Criteria 3, Criteria 1 plus positive maternal C-reactive protein and neutrophil left-shift into minor criteria. EONS included proven or suspected sepsis within 7 days following birth. Neonatal morbidity and mortality of EONS were also reviewed.

MAIN OUTCOME MEASURES

Diagnostic performance of three combinations.

RESULTS

The prevalence of EONS was 13.8%. Among 203 cases of EONS, maternal manifestation of clinical chorioamnionitis by criteria 1 was evident in only one out of seven, indicating 15.3% sensitivity for EONS prediction. However, with application of criteria 2, sensitivity significantly increased to 34.0%, while compromising specificity from 92.3% to 78.7%. Criteria 3 showed similar diagnostic performance compared with criteria 1 (sensitivity 16.7%, specificity 91.6%). Overall, neonatal mortality and neonatal composite morbidity in EONS were 14.9% and 67.8%, respectively, and there was no difference in neonatal morbidity and mortality between neonates whose mothers showed fever as a sign of clinical chorioamnionitis and those whose mothers did not.

CONCLUSION

The renouncement of fever as a prerequisite for the criteria of clinical chorioamnionitis could increase sensitivity for the identification of EONS, a serious outcome of preterm birth.

TWEETABLE ABSTRACT

The renouncement of fever as an essential can increase sensitivity for prediction of neonatal sepsis.

Role of selected cytokines in the etiopathogenesis of intraventricular hemorrhage in preterm newborns

Proinflammatory cytokines are essential mediators and indicators of an inflammatory process occurring in the body. Their physiological role is to stimulate the immune response, yet their excessive propagation and interaction with cells outside the immune system may be linked to the risk of organ damage. This is specifically important in the case of immature tissues of fetuses and prematurely born infants. Analysis of the concentrations of specific cytokines in different compartments makes it possible to assess the risk of premature birth, preterm rupture of the membranes, and to determine an existing intrauterine infection. The purpose of this paper is to summarize the existing research concerning the relationships between the concentrations of specific proinflammatory cytokines in different compartments (maternal blood serum, amniotic fluid, umbilical cord blood, arterial and venous blood, and cerebrospinal fluid of the newborn) and the risk of intraventricular hemorrhage (IVH) and the degree of its severity. The paper takes also into account the assessment of the usefulness of cytokines as biomarkers for IVH and its complications (posthemorrhagic hydrocephalus, white matter injury).

Elevated plasma and cerebrospinal fluid interleukin-1 beta and tumor necrosis factor-alpha concentration and combined outcome of death or abnormal neuroimaging in preterm neonates with early-onset clinical sepsis

OBJECTIVE

Prematurity and sepsis are the major contributors of neonatal mortality and neurodevelopmental sequelae. The present study was conducted to measure the plasma and cerebrospinal fluid (CSF) concentration of interleukin (IL)-1β and tumor necrotic factor (TNF)-α in preterm neonates with early-onset clinical sepsis (EOCS), and to find out their association with combined outcome of death or abnormal neuroimaging.

STUDY DESIGN

Thirty-two preterm (⩽34 weeks) neonates with EOCS and 32 gestational age-matched, healthy neonates served as cases and controls, respectively. Samples were collected soon after birth. Neonates were followed up clinically and by serial cranial ultrasonography (CUS) until discharge and subsequently by magnetic resonance imaging (MRI) of brain until 1 year. Developmental screening was done by Denver Developmental Screening test-II.

RESULT

In EOCS group, no neonate had any clinical/microbiological evidence of meningitis. Blood culture was positive in 17 (53%). CUS was abnormal in 12 (37%) (intracranial hemorrhage-11, periventricular leukomalacia-1). Ten (31%) neonates expired. Significant elevation of plasma and CSF IL-1β and TNF-α was observed in the EOCS group. On follow-up, seven (22%) neonates showed evidence of white matter damage in MRI, two of them had developmental delay and microcephaly. Plasma and CSF IL-1β and TNF-α concentration were significantly elevated in deceased neonates and those with abnormal neuroimaging. Both biomarkers demonstrated high predictive accuracy for poor outcome in receiver-operating curve analysis.

CONCLUSION

Elevation of plasma and CSF IL-1β and TNF-α is associated with an increase in the combined outcome of death or abnormal neuroimaging in preterm neonates with EOCS in the absence of clinical/microbiological evidence of meningitis with high predictive accuracy.

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.

A Systematic Review and Meta-analysis of the Timing of Early Intraventricular Hemorrhage in Preterm Neonates: Clinical and Research Implications

A considerable number of intraventricular hemorrhages (IVH) occur within the first hours of life (HOL). Temporality between IVH and its antecedents as well as a consistent definition of "early IVH" is lacking in a large and growing body of literature. We performed a systematic review of prospective studies that reported onset of IVH in preterm neonates within the first HOL and afterwards. The English literature was searched using three databases up to March 2013. Four timing periods of IVH can be compared in 16 identified studies: 0-6; 7-12; 13-24; after 24 HOL. The 0-6 and after 24 HOL were the major modes of IVH timing. Pooled IVH proportions were estimated through a meta-analysis of studies that were conducted after antenatal steroid and surfactant era. In neonates weighing ≤1500 g at birth: 48% of IVH (95% CI: 42-58%, 5 studies, 279 IVH cases) occurred during 0-6 HOL and 38% (95% CI: 19-57%, 4 studies, 241 IVH cases) after 24 HOL. The 0-6 HOL is the shortest, most vulnerable period for IVH, thus, an early IVH is an IVH occurs in it. Such early IVH had prognostic, etiological/preventive and medicolegal implications. Accordingly, preterm neonates at risk of IVH should have their first routine screening head ultrasound at about 6 HOL. Future research exploring the antecedents of IVH should guaranty the temporality between these antecedents and IVH. Additional research will be required to determine whether the long term neurological outcomes of early and late IVH are the same.

Chorioamnionitis in the pathogenesis of brain injury in preterm infants

Chorioamnionitis (or placental infection) is suspected to be a risk factor for brain injury in premature infants. The suggested association between chorioamnionitis and cystic periventricular leukomalacia and cerebral palsy is uncertain because of the variability of study designs and definitions of chorioamnionitis. Improvements in neonatal intensive care may have attenuated the impact of chorioamnionitis on brain health outcomes. Large multicenter studies using rigorous definitions of chorioamnionitis on placental pathologies and quantitative magnetic resonance techniques may offer the optimal way to clarify the complex role of chorioamnionitis in modifying brain health and long-term outcomes.

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.

Hypernatremia and grade III/IV intraventricular hemorrhage among extremely low birth weight infants

OBJECTIVE

To identify the risk factors contributing to intraventricular hemorrhage (IVH) in extremely low birth weight infants during early postnatal life, after appropriate matching for gestational age (GA) and birth body weight (BBW).

STUDY DESIGN

A case-control retrospective study was designed to evaluate preterm infants with a GA ≤ 26 weeks and a BBW ≤ 1000 g admitted to our hospital during a 7.5-year period. From a cohort of 347 preterm infants, 36 infants (10.7%) had severe IVH (grades III and/or IV). We selected a control group of 36 preterm infants without IVH who were closely matched for GA (± 1 week) and body weight (± 100 g). Univariate and multivariate logistic regression analyses were performed to identify risk factors for severe IVH.

RESULT

The GA and BBW of the IVH and control groups were 24.6 ± 1 weeks and 764.4 ± 118.5 g, and 24.8 ± 0.9 weeks and 771.5 ± 125.9 g, respectively. Vaginal delivery, male sex, resuscitation in the delivery room, high sodium serum levels (meq l(-1)) (162.6 vs 148.8), fluctuation of serum sodium (meq l(-1)) (17.3 vs 6.2), pH, PaCO(2), hemoglobin and platelet counts were associated with an increased risk of severe IVH. Multivariate logistic regression indicated that sodium fluctuations >13 meq l(-1), vaginal delivery, male sex and hemoglobin fluctuations are strongly associated with the development of severe IVH.

CONCLUSION

Hypernatremia and fluctuations of sodium seem to be related to early severe IVH among preterm infants; however, further studies are required to clarify the causal relationship.

Cord blood erythropoietin and interleukin-6 for prediction of intraventricular hemorrhage in the preterm neonate

OBJECTIVE

To evaluate cord blood erythropoietin (EPO) and interleukin-6 (IL-6) levels to predict preterm infants at risk of developing intraventricular hemorrhage (IVH).

METHODS

Levels of umbilical cord EPO, acid-base status and IL-6 were analyzed in 116 consecutive, preterm newborns (GA at delivery: 29 [23-34 ] weeks) born to mothers who had a clinically indicated amniocentesis to rule out infection. Early-onset neonatal sepsis (EONS) was diagnosed using symptoms, hematological criteria and blood cultures.

RESULTS

IVH was diagnosed by cranial ultrasounds. The prevalence of IVH in our population was 25% (29/116). There was a direct relationship between cord blood EPO and cord blood IL-6 concentration (r = 0.225, p = 0.014), independent of GA at birth. Elevated cord blood EPO levels (r = 0.182, p = 0.016) and GA at birth (r =  -0.236, p = 0.004) remained significant independent factors associated with the risk of IVH, when evaluated with stepwise logistic regression analyses. Cord blood IL-6, pH, and EONS were not associated with IVH. These relationships remained following correction for GA at birth (p = 0.027).

CONCLUSIONS

Our results suggest that elevation in cord blood EPO may predict newborns at risk for IVH, independent of fetal inflammatory status. Further studies are warranted to confirm this association.

Chorioamnionitis: a multiorgan disease of the fetus?

The bacterial infection of chorion and amnion is a common finding in premature delivery and is referred to as chorioamnionitis. As the mother rarely shows symptoms of a systemic inflammation, the course of chorioamnionitis is frequently asymptomatic and chronic. In contrast, the fetal inflammatory response syndrome represents a separate phenomenon, including umbilical inflammation and increased serum levels of proinflammatory cytokines in the fetus. Ascending maternal infections frequently lead to systemic fetal inflammatory reaction. Clinical studies have shown that antenatal exposure to inflammation puts the extremely immature neonates at a high risk for worsening pulmonary, neurological and other organ development. Interestingly, the presence of chorioamnionitis is associated with a lower rate of neonatal mortality in extremely immature newborns. In the following review, the pathogeneses of inflammation-associated perinatal morbidity are outlined. The concept of fetal multiorganic disease during intrauterine infection is introduced and discussed.

Chemokine CCL18 predicts intraventricular hemorrhage in very preterm infants

BACKGROUND

Intraventricular hemorrhage (IVH) in very preterm infants is a common disease associated with long-term consequences. Risk factors of IVH remain to be further defined.

AIMS

To determine whether specific immunoproteins at birth predict the risk of IVH and whether their receptors are localized at the bleeding site.

METHODS

A prospective cohort consisted of 163 infants born before 32 weeks of gestation. Altogether 107 cord blood immunoproteins and 12 cytokines from peripheral blood obtained 1 and 7 days after birth were analyzed. Serial brain ultrasounds were assessed. Immunohistochemistry of a chemokine receptor from 14 autopsies was studied.

RESULTS

Low levels of cord chemokine CCL18 (chemokine (C-C motif) ligand 18) robustly predicted the risk of IVH grade II-IV when ante- and neonatal risk factors were considered. Cord CCL18 increased from 32 weeks to term. During the first week after very preterm birth CCL18 increased as the risk of new IVH cases decreased. CCL18 receptor, CCR3, was detectable in choroid plexus, periventricular capillary endothelium, ependymal cells, and in germinal matrix.

CONCLUSION

Low cord blood CCL18 is an independent risk factor of IVH. CCL18 may inhibit signal transduction of its receptor in periventricular cells. Defining the function and regulation of CCL18 may help to decrease the risk of IVH.

Intracranial hemorrhage in the preterm infant: understanding it, preventing it

New discoveries in neonatal imaging, cerebral monitoring, and hemodynamics, and greater understanding of inflammatory and genetic mechanisms involved in intracranial hemorrhage (ICH) in the preterm infant are creating opportunities for innovative early detection and prevention approaches. This article covers the spectrum of ICH in the preterm infant, including germinal matrix intraventricular hemorrhage, its complications, and associated phenomena, such as the emerging role of cerebellar hemorrhage. The overall aim of this article is to review the current knowledge of the mechanisms, diagnosis, outcome, and management of preterm ICH; to revisit the origins from which they develop; and to discuss future expectations.

The role of systemic hemodynamic disturbances in prematurity-related brain injury

Premature infants who experience cerebrovascular injury frequently have acute and long-term neurologic complications. In this article, we explore the relationship between systemic hemodynamic insults and brain injury in this patient population and the mechanisms that might be at play.

A multicenter study on the clinical outcome of chorioamnionitis in preterm infants

OBJECTIVE

The purpose of this study was to examine the effects of clinical maternal chorioamnionitis on morbidity and mortality rates among infants who are at < 33 weeks of gestation, adjusted for patient characteristics that included admission neonatal illness severity (Score for Neonatal Acute Physiology, version II; SNAP-II).

STUDY DESIGN

With multivariate logistic regression analysis, prospectively collected hospital outcomes from the Canadian Neonatal Network of singleton infants with birth gestational age of < 33 weeks and clinical chorioamnionitis were compared retrospectively with nonexposed infants.

RESULTS

Of 3094 infants, 477 infants (15.4%) who were exposed to clinical chorioamnionitis had significantly higher admission SNAP-II scores. Bivariate analysis revealed that the neonatal mortality rate was increased significantly in the chorioamnionitis group (10.6% vs 6.1%). Multivariate regression analysis with adjustment for illness severity indicated that chorioamnionitis was associated with an increased risk of early sepsis (odds ratio, 5.54; 95% confidence interval, 2.87-10.69) and severe intraventricular hemorrhage (odds ratio, 1.62; 95% confidence interval, 1.17-2.24) but not neonatal death.

CONCLUSION

Preterm infants who are exposed to clinical chorioamnionitis have an increased risk of early-onset sepsis and severe intraventricular hemorrhage.