Association between funisitis and elevated interleukin-6 in cord blood

Funisitis as a Risk Factor for Adverse Neonatal Outcomes in Twin Neonates with Spontaneous Preterm Birth: A Retrospective Cohort Study

PURPOSE

Funisitis, inflammation of the umbilical cord, is considered a strong risk factor for adverse neonatal outcomes; however, a clinical definition of funisitis has not been established. In this study, we aimed to determine the clinical significance of funisitis in twin neonates with spontaneous preterm birth.

MATERIALS AND METHODS

The study included preterm twin neonates (<35 weeks) delivered after spontaneous preterm labor and/or preterm premature rupture of amniotic membranes. The presence of funisitis was examined in the umbilical cord of each twin. We analyzed the risk of adverse neonatal outcomes according to the presence and absence of funisitis. Adverse neonatal outcomes were defined as the occurrence of neonatal mortality, significant morbidity, or both.

RESULTS

Among 474 preterm neonates (237 twin pairs) included in this study, the frequency of funisitis was 6.5% (31 cases). Funisitis was significantly associated with neonatal mortality and adverse neonatal outcomes after adjustment for confounding variables [neonatal mortality, odds ratio (OR) 9.043, 95% confidence interval (CI) 2.620-31.204; adverse neonatal outcome, OR 2.445, 95% CI 1.017-5.875]. The concordance rate of funisitis between the twins was 10.7%, and in the absence of funisitis in one twin, the risk of neonatal mortality or adverse neonatal outcome was not influenced by the presence of funisitis in the other twin.

CONCLUSION

The presence of funisitis appears to be associated with an increased risk for adverse neonatal outcomes in twin neonates with spontaneous preterm birth.

Pulmonary Consequences of Prenatal Inflammatory Exposures: Clinical Perspective and Review of Basic Immunological Mechanisms

Chorioamnionitis, a potentially serious inflammatory complication of pregnancy, is associated with the development of an inflammatory milieu within the amniotic fluid surrounding the developing fetus. When chorioamnionitis occurs, the fetal lung finds itself in the unique position of being constantly exposed to the consequent inflammatory meditators and/or microbial products found in the amniotic fluid. This exposure results in significant changes to the fetal lung, such as increased leukocyte infiltration, altered cytokine, and surfactant production, and diminished alveolarization. These alterations can have potentially lasting impacts on lung development and function. However, studies to date have only begun to elucidate the association between such inflammatory exposures and lifelong consequences such as lung dysfunction. In this review, we discuss the pathogenesis of and fetal immune response to chorioamnionitis, detail the consequences of chorioamnionitis exposure on the developing fetal lung, highlighting the various animal models that have contributed to our current understanding and discuss the importance of fetal exposures in regard to the development of chronic respiratory disease. Finally, we focus on the clinical, basic, and therapeutic challenges in fetal inflammatory injury to the lung, and propose next steps and future directions to improve our therapeutic understanding of this important perinatal stress.

The relationship among the progression of inflammation in umbilical cord, fetal inflammatory response, early-onset neonatal sepsis, and chorioamnionitis

OBJECTIVES

No information exists about whether fetal inflammatory-response(FIR), early-onset neonatal sepsis(EONS) and chorioamnionitis(an advanced-stage of maternal inflammatory-response in extraplacental membranes) continuously increase according to the progression of inflammation in umbilical-cord(UC). The objective of current-study is to examine this-issue.

METHODS

Study-population included 239singleton pregnant-women(gestational-age[GA] at delivery: 21.6~36weeks) who had inflammation in extraplacental membranes or chorionic plate (CP) and either preterm-labor or preterm-PROM. We examined FIR, and the frequency of fetal inflammatory-responses syndrome(FIRS), proven-EONS, suspected-EONS and chorioamnionitis according to the progression of inflammation in UC. The progression of inflammation in UC was divided with a slight-modification from previously reported-criteria as follows: stage0, inflammation-free UC; stage-1: umbilical phlebitis only; stage-2: involvement of at least one UA and either the other UA or UV without extension into WJ; stage-3: the extension of inflammation into WJ. FIR was gauged by umbilical-cord-plasma(UCP) CRP concentration(ng/ml) at birth, and FIRS was defined as an elevated UCP CRP concentration at birth(≥200ng/ml).

RESULTS

Stage-0, stage-1, stage-2 and stage-3 of inflammation in UC were present in 48.1%, 15.5%, 6.7%, and 29.7% of cases. FIR continuously increased according to the progression of inflammation in UC(Kruskal-Wallis test,P<0.001; Spearman-rank-correlation test,P<0.000001,r = 0.546). Moreover, there was a significant and stepwise increase in the frequency of FIRS, proven-EONS, suspected-EONS and chorioamnionitis according to the progression of inflammation in UC(each for P<0.000005 in both chi-square test and linear-by-linear-association). Multiple logistic-regression analysis demonstrated that the more advanced-stage in the progression of inflammation in UC(i.e., stage-1 vs. stage-2 vs. stage-3), the better predictor of suspected-EONS (Odds-ratio[OR]3.358, 95%confidence-interval[CI]:1.020-11.057 vs. OR5.147, 95%CI:1.189-22.275 vs. OR11.040, 95%CI:4.118-29.592) and chorioamnionitis(OR6.593, 95%CI:2.717-15.999 vs. OR16.508, 95%CI:3.916-69.596 vs. OR20.167, 95%CI:8.629-47.137).

CONCLUSION

FIR, EONS and chorioamnionitis continuously increase according to the progression of inflammation in UC among preterm-gestations with inflammation in extraplacental membranes or CP. This finding may suggest that funisitis(inflammation in UC) is both qualitatively and quantitatively histologic-counterpart of FIRS, and a surrogate-marker for chorioamnionitis.

Microorganisms in the Placenta: Links to Early-Life Inflammation and Neurodevelopment in Children

Prenatal exposure to various stressors can influence both early and later life childhood health. Microbial infection of the intrauterine environment, specifically within the placenta, has been associated with deleterious birth outcomes, such as preterm birth, as well as adverse neurological outcomes later in life. The relationships among microorganisms in the placenta, placental function, and fetal development are not well understood. Microorganisms have been associated with perinatal inflammatory responses that have the potential for disrupting fetal brain development. Microbial presence has also been associated with epigenetic modifications in the placenta, as well other tissues. Here we review research detailing the presence of microorganisms in the placenta and associations among such microorganisms, placental DNA methylation, perinatal inflammation, and neurodevelopmental outcomes.

Placental Lesions in Meconium Aspiration Syndrome

Background

Meconium aspiration syndrome (MAS) is defined by respiratory distress requiring supplemental oxygen in a meconium-stained neonate. MAS is clinically subclassified as mild, moderate, and severe according to the oxygen requirement. The aims of this study were to compare the histological findings in the placentas of MAS neonates with those of meconium-stained but non-MAS neonates and to analyze the correlation between the severity of MAS and the grade of its histological parameters.

Methods

We collected 160 singleton term placentas from neonates with meconium staining at birth from a tertiary medical center, Seoul, Republic of Korea. We reviewed hematoxylin and eosin sections of tissue samples (full-thickness placental disc, chorioamniotic membranes, and umbilical cord).

Results

Funisitis was present more frequently in MAS than in non-MAS (p < .01), of which the stage was correlated with the severity of MAS (p < .001). The histological findings consistent with maternal underperfusion and chronic deciduitis were more frequent in MAS than in non-MAS (p < .05). There was a correlation between the degree of chorionic vascular muscle necrosis and the severity of MAS (p < .05).

Conclusions

Our results suggest that fetal inflammatory response evidenced by funisitis occurs prenatally in MAS and that the stage of funisitis and of chorionic vascular muscle necrosis may be a predictive marker of the severity of MAS.

The relationship between the intensity of intra-amniotic inflammation and the presence and severity of acute histologic chorioamnionitis in preterm gestation

OBJECTIVE

Acute histologic chorioamnionitis (HCA) is associated with an increased risk of perinatal mortality and morbidity. The purpose of this study was to determine the relationship between the intensity of intra-amniotic inflammation (IAI) and the severity of acute HCA in preterm gestation.

METHODS

The relationship between the intensity of IAI and the presence and severity of acute HCA was examined in 412 patients with singleton gestations who delivered within 120 h of transabdominal amniocentesis. The concentration of amniotic fluid (AF) matrix metalloproteinase (MMP)-8 was assayed to determine the presence and intensity of IAI. Acute HCA was defined as the presence of inflammatory change in any tissue samples according to the criteria previously reported. The total grade of acute HCA was used to determine the severity of HCA.

RESULTS

(1) Patients with IAI had a significantly higher rate of acute HCA than those without IAI [76.9% (133/173)] versus 20.9% (50/239), p < 0.001]. The AF MMP-8 concentration was significantly higher in patients with acute HCA than in those without acute HCA (median [range]; 188.3 ng/ml [0.3-6142.6] versus 1.8 ng/ml [0.3-2845.5], p < 0.001); (2) Of 183 patients with acute HCA, the AF MMP-8 concentration was positively correlated with the severity of acute HCA (p < 0.001).

CONCLUSIONS

AF MMP-8 concentration was not only a predictor of the presence of acute HCA, but its concentration also correlated with the severity of acute HCA. The higher the intensity of IAI, the worse the degree of acute HCA in preterm gestation.

Leukocytosis as a prognostic marker in the development of fetal inflammatory response syndrome

OBJECTIVE

To identify and evaluate the correlation between leukocyte count in maternal blood and the risk of developing fetal inflammatory response syndrome (FIRS).

PATIENTS AND METHODS

The study involved 158 infants born at 22 - 34 weeks of gestation and their mothers. Umbilical cord blood cytokines were evaluated in immunoassay tests and maternal blood was tested for the leukocyte formula.

RESULTS

The period of gestation was significantly shorter in the FIRS group compared to the control group (29.5±3.1 vs. 32.2±2.4 weeks, p<0.001). Gestational age was ≤30 weeks for 53.8% of the newborns in the FIRS group and 15.8% of the newborns in the control group (p<0.001). The number of leukocytes in maternal blood before and during labor was significantly higher in the FIRS group than in the control group (p=0.034 and 0.004, respectively). The study determined the correlation between the total leukocyte count in maternal blood and IL-6 concentration during labor (p=0.05) and tumor necrosis factor (TNF-α) concentration in umbilical cord blood before and during labor (p=0.02 and 0.007, respectively).

CONCLUSION

Leukocytosis in the FIRS group was significantly higher than in the control group before and during labor. According to our data, one of the possible indicators of intrauterine infection could be the number of leukocytes in maternal blood.

A clinical prediction rule for histological chorioamnionitis in preterm newborns

Background

Histological chorioamnionitis (HC) is an intrauterine inflammatory process highly associated with preterm birth and adverse neonatal outcome. HC is often clinically silent and diagnosed postnatally by placental histology. Earlier identification could facilitate treatment individualisation to improve outcome in preterm newborns.

Aim

Develop a clinical prediction rule at birth for HC and HC with fetal involvement (HCF) in preterm newborns.

Methods

Clinical data and placental pathology were obtained from singleton preterm newborns (gestational age ≤32.0 weeks) born at Erasmus UMC Rotterdam from 2001 to 2003 (derivation cohort; n = 216) or Máxima MC Veldhoven from 2009 to 2010 (validation cohort; n = 206). HC and HCF prediction rules were developed with preference for high sensitivity using clinical variables available at birth.

Results

HC and HCF were present in 39% and 24% in the derivation cohort and in 44% and 22% in the validation cohort, respectively. HC was predicted with 87% accuracy, yielding an area under ROC curve of 0.95 (95%CI = 0.92–0.98), a positive predictive value of 80% (95%CI = 74–84%), and a negative predictive value of 93% (95%CI = 88–96%). Corresponding figures for HCF were: accuracy 83%, area under ROC curve 0.92 (95%CI = 0.88–0.96), positive predictive value 59% (95%CI = 52–62%), and negative predictive value 97% (95%CI = 93–99%). External validation expectedly resulted in some loss of test performance, preferentially affecting positive predictive rather than negative predictive values.

Conclusion

Using a clinical prediction rule composed of clinical variables available at birth, HC and HCF could be predicted with good test characteristics in preterm newborns. Further studies should evaluate the clinical value of these rules to guide early treatment individualisation.

Maternal serum interleukin-6 levels predict impending funisitis in preterm premature rupture of membranes after completion of antibiotics

OBJECTIVE

To determine if maternal serum interleukin-6 (IL-6) levels remain predictive of funisitis after completion of antibiotic administration in preterm premature rupture of membranes (PPROM).

METHODS

A secondary analysis of a prospective cohort study. Daily blood samples obtained from PPROM subjects were analyzed for IL-6 by enzyme-linked immunosorbent assay. Subjects (N = 39) delivered >7 days post admission and were divided into those with and without funisitis. Data were analyzed using Mann-Whitney U test.

RESULTS

Maternal serum IL-6 levels obtained 24-48 hours and 48-72 hours before delivery are elevated in PPROM subjects with funisitis compared to those without funisitis (6.3 vs. 2.7 pg/ml, P < 0.03; 6.1 vs. 1.7 pg/ml, P < 0.02). Receiver operator characteristic curve revealed an IL-6 level of 1.98 pg/ml had sensitivity of 86.7%, specificity of 46.7%, positive predictive value of 61.9% and negative predictive value of 77.8%.

CONCLUSION

This data suggests that maternal serum IL-6 levels continue to be predictive of PPROM subjects destined to develop funisitis after completion of antibiotics.

Biomarkers for diagnosis of neonatal infections: A systematic analysis of their potential as a point-of-care diagnostics

BACKGROUND

Neonatal infections annually claim lives of 1.4 million neonates worldwide. Until now, there is no ideal diagnostic test for detecting sepsis and thus management of possible sepsis cases often depends on clinical algorithm leading to empirical treatment. This often results in unnecessary antibiotic use, which may lead to emergence of antibiotic resistance. Biomarkers have shown great promise in diagnosis of sepsis and guiding appropriate treatment of neonates. In this study, we conducted a literature review of existing biomarkers to analyze their status for use as a point-of-care diagnostic in developing countries.

METHODS

PubMed and EMBASE database were searched with keywords, 'infections', 'neonates', and 'biomarkers' to retrieve potentially relevant papers from the period 1980 to 2010. Leading hospitals and manufacturers were communicated to inquire about the cost, laboratory requirements and current standing of biomarkers in clinical use.

RESULTS

The search returned 6407 papers on biomarkers; 65 were selected after applying inclusion and exclusion criteria. Among the studies, C-reactive protein (CRP), procalcitonin (PCT) and interleukin 6 (IL-6) were the most widely studied biomarkers and were considered to be most promising for diagnosing neonatal infections. About 90% of the studies were from developed countries; more than 50% were from Europe.

CONCLUSIONS

Extensive work is being performed to find the diagnostic and prognostic value of biomarkers. However, the methodologies and study design are highly variable. Despite numerous research papers on biomarkers, their use in clinical setting is limited to CRP. The methods for detection of biomarkers are far too advanced to be used at the community level where most of the babies are dying. It is important that a harmonized multi-site study is initiated to find a battery of biomarkers for diagnosis of neonatal infections.

Funisitis and chorionic vasculitis: relation to chorioamnionitis, timing and scoring

Five hundred consecutive cases with histologic chorioamnionitis and umbilical cord inflammation were analyzed to develop a staging system for funisitis and to correlate stage of funisitis with stage of chorioamnionitis in order to estimate the timing of various stages of funisitis. Funisitis progresses through venous involvement (with or without Wharton's jelly inflammation) to arterial involvement without Wharton's jelly and then full involvement of all three vessels and surrounding Wharton's jelly. Arterial involvement and full funisitis are strongly associated with stage III/IV chorioamnionitis, and imply a significant time interval following the onset of amniotic cavity inflammation.

Fetal inflammatory response and brain injury in the preterm newborn

Preterm birth can be caused by intrauterine infection and maternal/fetal inflammatory responses. Maternal inflammation (chorioamnionitis) is often followed by a systemic fetal inflammatory response characterized by elevated levels of proinflammatory cytokines in the fetal circulation. The inflammation signal is likely transmitted across the blood-brain barrier and initiates a neuroinflammatory response. Microglial activation has a central role in this process and triggers excitotoxic, inflammatory, and oxidative damage in the developing brain. Neuroinflammation can persist over a period of time and sensitize the brain to subinjurious insults in early and chronic phases but may offer relative tolerance in the intermediate period through activation of endogenous anti-inflammatory, protective, and repair mechanisms. Neuroinflammatory injury not only destroys what exists but also changes what develops.

Relationships between umbilical cord arterial blood pH levels at delivery and Bayley Psychomotor Development Index scores in early childhood

AIMS

To correlate data on umbilical cord arterial blood pH (pHa) levels obtained at delivery with subsequent Bayley Psychomotor Development (PDI) scores determined on the same cohort of children at age 18 months.

METHODS

At delivery, we obtained umbilical cord bloods for pHa levels along with other biological parameters. Following the birth cohort prospectively, at age 18 months we did a comprehensive, blinded neurodevelopmental examination to determine a PDI score for each child.

RESULTS

Over the broad range of umbilical cord arterial blood pH levels from 7.03 to 7.52, no statistically significant correlation (Pearson correlation coefficient, -0.016, P=0.88) was found between pHa at delivery and PDI scores at age 18 months. To study our finding in greater detail, we formed a subset of the data consisting only of lower pHa levels at delivery (defined as <or=7.20) and subsequent PDI scores. In this data subset, we again found that no significant relationship existed (Pearson correlation coefficient, +0.003, P=0.99).

CONCLUSIONS

Our findings are consistent with the evolving hypothesis that adverse neurological outcomes in children often have etiologies other than intrapartum fetal acidemia.

Impact of clinical and histologic correlates of maternal and fetal inflammatory response on gestational age in preterm births

OBJECTIVE

To evaluate the impact of clinical and histopathologic correlates related to maternal and fetal inflammatory responses (MIR and FIR) on degree of preterm birth.

METHODS

Pathology reports and clinical data from 577 singleton preterm births (<37 weeks of gestation) that took place between 1998 and 2004 were analyzed according to decreasing gestational age (>or=33 weeks, 29-32 weeks, and <29 weeks). MIR was defined by presence of subchorionitis, chorioamnionitis, deciduitis, or free membranitis; FIR was defined by presence of funisitis or chorionic plate vasculitis. The associations between MIR alone and MIR with FIR and gestational age subgroups were assessed using logistic regression.

RESULTS

The presence of FIR in addition to MIR was more strongly associated with degree of prematurity than the presence of MIR alone, especially for those born at <29 weeks (OR=10.1 (95% CI 4.3-23.7) and OR=5.3 (95% CI 2.3-12.5), respectively). These associations remained significant after adjusting for maternal race, clinical signs of chorioamnionitis, medically indicated birth, and intrapartum corticosteroid, tocolysis and antibiotic use, and after stratification by clinical signs of chorioamnionitis and medically indicated birth.

CONCLUSIONS

The combined presence of MIR and FIR is associated with a higher risk of extreme preterm birth (<29 weeks) than MIR alone, suggesting a contributory role of FIR in the pathophysiology of preterm birth.

The value of cord blood interleukin-6 levels for predicting chorioamnionitis, funisitis and neonatal infection in term premature rupture of membranes

OBJECTIVE

The objective was to determine whether the interleukin-6 (IL-6) level in umbilical cord blood can be used for the prediction of histologic chorioamnionitis, funisitis, fetal membrane cultures and neonatal infection.

STUDY DESIGN

A case-control study was conducted on 30 controls (control group) and on 40 women with term premature rupture of the membranes (PROM group). The interleukin-6 concentration of cord blood was measured. Fetal membranes and newborn blood were cultured. Placentas were examined for histologic chorioamnionitis and funisitis. Receiver operator curve analysis was used to obtain a cut-off value of interleukin-6 concentration for predicting histological and clinical infection.

RESULTS

The mean interleukin-6 level in cord blood was significantly higher in the PROM group (p=0.01). Histological chorioamnionitis and positive placental cultures were significantly higher in the PROM group (p=0.006 and 0.02, respectively). The PROM group had seven (17.5%) cases of funisitis and positive newborn blood cultures while neither was observed in the control group. A cord blood interleukin-6 level >29 pg/ml was found to have 84% sensitivity and 72.5% specificity for predicting positive placental cultures and 74.1% sensitivity and 76.7% specificity for identifying cases of histologic chorioamnionitis. For predicting funisitis and positive newborn cord blood cultures a cord blood interleukin-6 level >39 pg/ml has 100% sensitivity and 81% specificity.

CONCLUSION

Cord blood interleukin-6 level can be a tool for the evaluation of the extent of maternal-fetal infection and guides proper planning of the treatment.

Preterm labor, preterm premature rupture of membranes, and chorioamnionitis

In this article, the author reviews the etiology and biochemical links between infection and preterm birth, the problem of preterm birth, and the management of infection-related risks of preterm birth. The management section reviews current opinions regarding prophylactic antibiotic therapy in the prevention of preterm birth, adjunctive antibiotic therapy in the treatment of preterm labor with and without rupture of membranes, and antibiotic therapy of intra-amniotic infection (clinical chorioamnionitis, IAI). Finally, the article reviews the risk of neurodevelopmental handicap potentially associated with IAI.

Antenatal steroids may reduce adverse neurological outcome following chorioamnionitis: neurodevelopmental outcome and chorioamnionitis in premature infants

OBJECTIVE

To examine the effect of antenatal steroid exposure and in utero inflammation on the development of severe intraventricular haemorrhage, periventricular leukomalacia and long-term neurological outcome in infants less than 30 completed weeks gestation.

METHOD

Infants less than 30 completed weeks gestation from January 1996 to July 2001 were identified from a prospectively managed database. Placental pathology was reviewed for the presence or absence of chorioamnionitis and funisitis. Infants were divided into three groups depending on the degree of exposure to fetal inflammation (no inflammation, chorioamnionitis only and chorioamnionitis and funisitis). Data relating to gestational age, birthweight, sex, antenatal steroid exposure, surfactant treatment, days of positive pressure ventilation and days of oxygen requirement were collected. Cerebral ultrasound studies were examined for evidence of intraventricular or intraparenchymal echodensity and periventricular leukomalacia. Long-term neurological outcome was assessed by neurological examination for cerebral palsy and by Griffiths Mental Developmental Assessment for general developmental quotient.

RESULTS

Two hundred and twenty infants were identified. The mean gestational age was 27.7 weeks and the mean birthweight 1092 g. Seventy-two per cent of mothers had received a complete course of antenatal steroids. The risk of Grade III intraventricular haemorrhage or intraparenchymal echodensity was associated with exposure to in utero inflammation if a complete course of antenatal steroids had not been received (P = 0.002). This association did not exist if a complete course of antenatal steroids was given (P = 0.62). Fourteen infants had cerebral palsy (7%). The presence of cerebral palsy was also associated with in utero inflammation in the absence of complete antenatal steroid cover (P = 0.03) and not in the presence of complete cover (P = 0.59). The mean general developmental quotient on Griffiths Mental Developmental Assessment at 12 months or 3 years was not affected by exposure to in utero inflammation regardless of antenatal steroid exposure.

CONCLUSION

Risk of intraventricular haemorrhage or intraparenchymal echodensity and cerebral palsy was associated with in utero inflammation in the absence of a complete course of antenatal steroids. A complete course of antenatal steroids appeared to extinguish any association between in utero inflammation and adverse neurological outcome.

Activation of umbilical cord endothelial cells and fetal inflammatory response in preterm infants with chorioamnionitis and funisitis

Chorioamnionitis and funisitis are associated with preterm labor and postnatal morbidity. Activation of endothelium resulting in up-regulation of adhesion molecules seems to be a key mechanism in development of organ damage. We investigated whether chorioamnionitis with or without funisitis in preterm infants induced expression and shedding of adhesion molecules in the umbilical cord and resulted in increased concentrations of E-selectin, intercellular adhesion molecule (ICAM)-1, IL-1beta, IL-6, and IL-8 in the cord blood. Data were obtained by using immunohistochemistry and ELISA. Thirty-two preterm infants were divided into three groups according to histology: chorioamnionitis with funisitis, chorioamnionitis without funisitis, and controls without signs of inflammation. ICAM-1 expression on arterial endothelium was higher with funisitis compared with chorioamnionitis alone or with the control group. Similar results for ICAM-1 expression were found in venous endothelium, vascular walls, Wharton's jelly, and amnion epithelium. Endothelial E-selectin and vascular cell adhesion molecule (VCAM)-1 expression was only induced significantly with funisitis. Serum-concentrations of soluble ICAM-1 were higher with funisitis compared with chorioamnionitis alone or control group. Similarly, concentrations of soluble E-selectin, IL-1beta, IL-6, and IL-8 were increased exclusively with funisitis. In conclusion, only chorioamnionitis with funisitis was associated with systemic inflammation and endothelial activation with up-regulation and shedding of umbilical cord adhesion molecules. We speculate that this activation of endothelium may not be limited to the umbilical cord but may also involve other organs resulting in neonatal morbidity. This underlines the importance of funisitis as a risk factor for adverse outcome.

Second overview of relationships between antenatal pharmacologic magnesium sulfate and neurologic outcomes in children

In the last ten years, the body of scientific knowledge concerning the use of antenatal pharmacologic magnesium sulfate (MgSO4) has become substantially larger. Several randomized controlled trials have provided compelling evidence that MgSO4 is the drug of choice for maternal seizure prophylaxis in toxemia. In contrast, the recent Cochrane Systematic Review, as well as other studies, have shown there is no evidence basis for the use of MgSO4 for tocolysis. Furthermore, when tocolytic-strength doses of MgSO4 are employed, there is an excess risk for total pediatric mortality (Cochrane Systematic Review and our own previous work). It is conceivable, nonetheless, that low doses of MgSO4, when used as prophylaxis in some selected cases of preterm labor, may ultimately be shown to be neuroprotective for a relatively small number of children. Unfortunately, the indiscriminate use of high-dosage MgSO4 for attempted tocolysis in preterm labor is much more likely to cause harm than do good.

Interferon-gamma expression in periventricular leukomalacia in the human brain

Periventricular leukomalacia (PVL), the major lesion underlying cerebral palsy in survivors of prematurity, is characterized by focal periventricular necrosis and diffuse gliosis of immature cerebral white matter. Causal roles have been ascribed to hypoxiaischemia and maternal-fetal infection, leading to cytokine responses, inflammation, and oligodendrocyte cell death. Because interferon-gamma (IFN-gamma) is directly toxic to immature oligodendrocytes, we tested the hypothesis that it is expressed in PVL (N = 13) compared to age-adjusted controls (N = 31) using immunocytochemistry. In PVL, IFN-gamma immunopositive macrophages were clustered in necrotic foci, and IFN-gamma immunopositive reactive astrocytes were present throughout the surrounding white matter (WM). The difference in the number of IFN-gamma immunopositive glial cells/high power field (IFN-gamma score, Grades 0-3) between PVL cases (age-adjusted mean 2.59+/-0.25) and controls (age-adjusted mean 1.39+/-0.16) was significant (p<0.001). In the gliotic WM, the IFN-gamma score correlated with markers for lipid peroxidation, but not nitrative stress. A subset of premyelinating (04+) oligodendrocytes expressed IFN-gamma receptors in PVL and control cases, indicating that these cells are vulnerable to IFN-gamma toxicity via receptor-mediated interactions. In PVL, IFN-gamma produced by macrophages and reactive astrocytes may play a role in cytokine-induced toxicity to premyelinating oligodendrocytes as part of a cytokine response stimulated by ischemia and/or infection.

C-reactive protein in umbilical cord blood: a simple and widely available clinical method to assess the risk of amniotic fluid infection and funisitis

OBJECTIVE

The purpose of this study was to determine whether concentrations of C-reactive protein (CRP) in umbilical cord plasma at birth were elevated in neonates with sepsis, an inflammatory lesion of the umbilical cord (funisitis) or who were born to mothers with microbial invasion of the amniotic cavity.

METHODS

Umbilical cord plasma was collected at birth from 313 singleton preterm neonates (20-35 weeks of gestation). The results of amniotic fluid culture performed within 5 days of birth, the occurrence of congenital neonatal sepsis and the presence of funisitis were assessed. Amniocentesis was performed in 152 patients within 5 days of birth. Amniotic fluid was cultured for aerobic and anaerobic bacteria and for mycoplasmas. The CRP concentration was measured with a highly sensitive immunoassay.

RESULTS

The median cord plasma CRP concentration was significantly higher in neonates with a positive amniotic fluid culture than in those with negative culture (median 245.9 (range 11.6-4885.5) ng/ml vs. median 44.3 (range 2.3-7401.8) ng/ml; p < 0.001), in those with congenital proven sepsis than in those without this complication (median 789.5 (range 20.4-2584.3) ng/ml vs. median 41.5 (range 1.3-7401.8) ng/ml; p < 0.005) and in neonates with funisitis than in those without funisitis (median 403.8 (range 4.9-10897.4) ng/ml vs. median 31.0 (range 1.3-7401.8) ng/ml; p < 0.001). The sensitivity of CRP in the identification of amniotic fluid infection, neonatal sepsis and funisitis was similar to that of interleukin-6 (> 17.5 pg/ml). However, the specificity of CRP in the identification of neonatal sepsis and funisitis was significantly higher than that of interleukin-6 (74% vs. 69%, p < 0.05; 83% vs. 76%, p < 0.01).

CONCLUSION

Umbilical cord plasma CRP concentrations were elevated in patients with amniotic fluid infection, congenital neonatal sepsis and funisitis.

Pulmonary fluorodeoxyglucose uptake in infants of very low birth weight with and without intrauterine inflammation

OBJECTIVE

We compared early pulmonary (18)fluorodeoxyglucose ((18)FDG) uptake in infants who had very low birth weight with and without exposure to intrauterine inflammation by using positron emission tomography (PET). A secondary goal was to correlate (18)FDG uptake with later death or bronchopulmonary dysplasia.

METHODS

Within 72 hours of birth, 22 singleton infants between 25 and 30 weeks of gestation had a thoracic PET scan after intravenous (18)FDG. Influx constants (K(i)) for (18)FDG were determined. Placental histology assessed exposure to intrauterine inflammation.

RESULTS

Chorioamnionitis was found in 13 infants. Seven of these infants also had evidence of funisitis. No inflammation was detected in the remaining nine infants. Median (minimum, maximum) thoracic K(I) was 0.008 (0.006, 0.011) mL/min/mL in infants with funisitis, 0.006 (0.002, 0.008) in infants with chorioamnionitis only, and 0.006 (0.001, 0.015) in infants with no evidence of intrauterine inflammation (P=.16). No relation was found between K(i) and later death or bronchopulmonary dysplasia. Cord blood interleukin-6 was elevated in newborns with placental inflammation (P=.014).

CONCLUSION

Early thoracic PET scanning for metabolically active inflammatory cells does not differ between infants with and without exposure to intrauterine inflammation. Evidence of early intrapulmonary sequestration of inflammatory cells in some infants without chorioamnionitis points to the complex etiology of postnatal inflammation.

Components of the systemic fetal inflammatory response syndrome as predictors of impaired neurologic outcomes in children

OBJECTIVE

The purpose of this study was to compare interleukin-6 and funisitis as predictors of impaired neurologic outcomes in children by performing a secondary analysis on data that were collected prospectively for another purpose.

STUDY DESIGN

We examined umbilical cords for funisitis and obtained cord blood for interleukin-6 levels. A psychomotor developmental index score was determined for each child at age 18 months.

RESULTS

The prevalence (46%) of elevated interleukin-6 levels (> or = 10 pg/mL) among children with low psychomotor developmental index scores (<100) was not significantly different from that of children with normal scores (47%). Among children with funisitis (n = 21), the median psychomotor developmental index score was 94; for children without funisitis (n = 92), it was 99 (P <.02). When the data were regressed for confounding, funisitis remained significant (adjusted odds ratio, 1.3; 95% CI, 1.1-1.9). Furthermore, funisitis was a more specific predictor of low psychomotor developmental index scores (P <.001), although elevated interleukin-6 levels were more sensitive.

CONCLUSION

When used for the prediction of impaired neurologic outcomes in children, funisitis has better specificity and thus a better positive predictive value than does interleukin-6.

Association between the use of antenatal magnesium sulfate in preterm labor and adverse health outcomes in infants

OBJECTIVE

The purpose of this study was to determine whether the use of antenatal magnesium sulfate prevents adverse outcomes (neonatal intraventricular hemorrhage, periventricular leucomalacia, death, and cerebral palsy).

STUDY DESIGN

In a controlled trial, we randomized mothers in preterm labor to magnesium sulfate, "other" tocolytic, or placebo. At delivery, umbilical cord blood was collected for the later determination of serum ionized magnesium levels. Neonatal cranial ultrasound scans were obtained periodically for the diagnosis of intraventricular hemorrhage and periventricular leucomalacia. Among survivors, the diagnosis of cerebral palsy was made at age 18 months.

RESULTS

Children with adverse outcomes had higher umbilical cord magnesium levels at delivery. In regression models that controlled for confounders, which included very low birth weight, magnesium remained a significant risk factor (adjusted odds ratio, 3.7; 95% CI, 1.1-11.9; P =.03).

CONCLUSION

Contrary to original hypotheses, this randomized trial found that the use of antenatal magnesium sulfate was associated with worse, not better, perinatal outcome in a dose-response fashion.

Association between maternal serum ionized magnesium levels at delivery and neonatal intraventricular hemorrhage

OBJECTIVES

To determine whether magnesium sulfate (MgSO(4)) exposure is associated with a reduced risk for neonatal intraventricular hemorrhage (IVH).

STUDY DESIGN

In a randomized, controlled trial, women in preterm labor were randomly assigned to receive MgSO(4), "other" tocolytic, or saline control. At delivery, we collected maternal antecubital and umbilical cord blood for determination of serum ionized magnesium levels. Neonatal IVH was diagnosed by cranial ultrasonogram.

RESULTS

Among 144 infants, 24 were diagnosed with IVH. Using crude intention-to-treat analysis, we found that 18% (13/74) of survivors exposed after birth to MgSO(4) had IVH compared with 16% (11/70) of babies who were not exposed. Infants who had IVH were more likely to have been delivered by mothers with higher serum ionized magnesium (Mg) levels (0.75 vs 0.56 mmol/L) (P =.01). Using multivariable logistic regression, we confirmed that higher Mg levels are a significant predictor of neonatal IVH (adjusted odds ratio, 15.8; 95% CI, 1.4-175.0) even when adjusted for birth weight, gestational age, antenatal hemorrhage, and neonatal glucocorticoid exposure.

CONCLUSIONS

In mothers with preterm labor, our data indicate that antenatal MgSO(4) exposure may be associated with an increased risk for IVH among their newborns.