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

Correlation between intrapartum CTG findings and interleukin-6 levels in the umbilical cord arterial blood: A prospective cohort study

OBJECTIVE

to investigate the correlation between the intrapartum CardioTocoGraphic (CTG) findings "suggestive of fetal inflammation" ("SOFI") and the interleukin (IL)-6 level in the umbilical arterial blood.

STUDY DESIGN

prospective cohort study conducted at a tertiary maternity unit and including 447 neonates born at term.

METHODS

IL-6 levels were systematically measured at birth from a sample of blood taken from the umbilical artery. The intrapartum CTG traces were retrospectively reviewed by two experts who were blinded to the postnatal umbilical arterial IL-6 values as well as to the neonatal outcomes. The CTG traces were classified into "suggestive of fetal inflammation (SOFI)" and "no evidence of fetal inflammation (NEFI) according to the principles of physiologic interpretation the CTG traces. The CTG was classified as "SOFI" if there was a persistent fetal heart rate (FHR) increase > 10 % compared with the observed baseline FHR observed at the admission or at the onset of labor without any preceding repetitive decelerations. The occurrence of Composite Adverse Outcome (CAO) was defined as Neonatal Intensive Care Unit (NICU) or Special Care Baby Unit (SCBU) admission due to one or more of the following: metabolic acidaemia, Apgar score at 5 min ≤ 7, need of neonatal resuscitation, respiratory distress, tachypnoea/polypnea, jaundice requiring phototherapy, hypotension, body temperature instability, poor perinatal adaptation, suspected or confirmed early neonatal sepsis.

MAIN OUTCOME MEASURES

To compare the umbilical IL-6 values between the cases with intrapartum CTG traces classified as "SOFI" and those classified as "NEFI"; to assess the correlation of umbilical IL-6 values with the neonatal outcome.

RESULTS

43 (9.6 %) CTG traces were categorized as "SOFI"; IL-6 levels were significantly higher in this group compared with the "NEFI" group (82.0[43.4-325.0] pg/ml vs. 14.5[6.8-32.6] pg/mL; p <.001). The mean FHR baseline assessed 1 h before delivery and the total labor length showed an independent and direct association with the IL-6 levels in the umbilical arterial blood (p <.001 and p = 0.005, respectively). CAO occurred in 33(7.4 %) cases; IL-6 yielded a good prediction of the occurrence of the CAO with an AUC of 0.72 (95 % CI 0.61-0.81).

CONCLUSION

Intrapartum CTG findings classified as "SOFI" are associated with higher levels of IL-6 in the umbilical arterial blood.

Inflammatory Biomarker Profiles in Very Preterm Infants within the Context of Preeclampsia, Chorioamnionitis, and Clinically Diagnosed Postnatal Infection

Preterm delivery can be precipitated by preeclampsia or infection, and preterm infants are at heightened risk of postnatal infection. Little is known about the ontogeny of inflammatory biomarkers in extremely preterm infants. We hypothesized that suspected prenatal infection (clinical chorioamnionitis or spontaneous preterm labor) and clinically diagnosed postnatal infection would be associated with unique biomarker signatures, and those patterns would be influenced by the degree of prematurity. Venous blood was collected daily for the first week and weekly for up to 14 additional weeks from 142 neonates born at 22-32 weeks gestation. A custom array was utilized to measure monocyte chemoattractant protein-1 (MCP-1) and interleukin-6 (IL-6). C-reactive protein (CRP) levels were obtained from the electronic medical record. Independent of gestational age, MCP-1 was significantly increased (p < 0.001) in association with maternal preeclampsia, but MCP-1 was decreased (p < 0.01), and CRP was increased (p < 0.01) in the presence of chorioamnionitis with funisitis. IL-6 and CRP were both increased in infants diagnosed with postnatal infection, with peak levels observed on days 2 and 3, respectively. In conclusion, suspected prenatal and postnatal infections and non-infectious complications of pregnancy are associated with unique biomarker profiles, independent of gestational age, including over a 2-fold increase in MCP-1 among newborns of mothers with preeclampsia. Further, in those clinically diagnosed with a postnatal infection in the absence of antenatal infection concerns, IL-6 increases before CRP, emphasizing a potential role for expanded biomarker screening if antibiotics are initially avoided in infants delivered for maternal indications.

Placental clearance not synthesis tempers exaggerated pro-inflammatory cytokine response in neonates exposed to chorioamnionitis

BACKGROUND

The source and clearance of cytokines in the fetal circulation in term pregnancies complicated by chorioamnionitis remains unclear as are the contributions of placental transport, synthesis, and clearance. The objectives of the study were to determine (1) fetal and/or placental contributions to synthesis and/or clearance of inflammatory and anti-inflammatory cytokines in term pregnancies complicated by chorioamnionitis and (2) whether this differs in pregnancies further complicated by fetal hypoxia.

METHODS

Prospective cohort study of pregnancies >37 weeks gestational age that included: Group 1, uncomplicated cesarean delivery without labor (n = 20); Group 2, uncomplicated vaginal delivery (n = 30); Group 3, pregnancies complicated by chorioamnionitis (n = 10); Group 4, complicated by chorioamnionitis + fetal hypoxia (n = 10). Umbilical arterial (UmA) and venous (UmV) blood were assayed for IL-1β, IL-2, IL-6, IL-8, TNFα, and IL-10.

RESULTS

IL-6 and IL-8 were below assay detection in UmA and UmV blood in Group 1 and increased in Group 2 (P < 0.01), UmA»UmV (P < 0.01). Their concentrations increased further in Groups 3 and 4 (P = 0.003), UmA»UmV. Placental clearance was concentration dependent that approaches saturation in the presence of chorioamnionitis.

CONCLUSIONS

Marked increases in fetal synthesis of IL-6 and IL-8 occur in chorioamnionitis. Synthesis increase further when complicated by fetal hypoxia. Cytokine removal occurs via placental concentration-dependent mechanisms, potentially contributing to adverse fetal effects.

IMPACT

The source and role of the placenta in synthesis and/or clearance of inflammatory mediators in term pregnancies complicated by clinical chorioamnionitis are unclear; however, conventional wisdom suggests the placenta is their source. This is the first study demonstrating that circulating concentrations of fetal IL-6 and IL-8 in clinical chorioamnionitis ± birth asphyxia in term pregnancies are of fetal origin. Circulating fetal inflammatory cytokines are cleared by concentration-dependent placental mechanisms that are nearly saturated in chorioamnionitis ± fetal hypoxia. These observations provide additional insight into understanding the fetal immune response in term pregnancies complicated by clinical chorioamnionitis.

Association between interleukin-6 levels in amniotic fluid after rupture of membranes during labour at term pregnancy and successful vaginal delivery: a prospective cohort study

We compared the mean interleukin-6 (IL-6) level in the amniotic fluid after rupture of membranes during labour at term pregnancy according to the delivery methods through prospective cohort study. Cases with premature rupture of membranes, multifetal pregnancy, and major congenital anomalies were excluded. Amniotic fluid was obtained from vaginal canal immediately after spontaneous rupture of membranes. A total of 47 cases were analysed, and 72.3% (34/47) had successful vaginal delivery. The mean concentration of IL-6 in the amniotic fluid was significantly higher in the vaginal delivery group than in the caesarean section group (5,229 pg/mL vs. 1,702 pg/mL, p = .022). The concentration of IL-6 from the amniotic fluid tended to increase as the cervical dilatation increased. The association between high IL-6 level (>2,500 pg/mL) and successful vaginal delivery was not significant after adjusting the degree of cervical dilatation in multivariate logistic regression analysis. IMPACT STATEMENTWhat is already known on this subject? Multiparity, active and strong uterine contractions, dilated cervical os, and the position of foetal head are known clinical factors affecting the successful vaginal delivery. There are few studies on markers for successful vaginal delivery in patients with labour.What do the results of this study add? The mean value of IL-6 concentration from the amniotic fluid collected from vagina immediately after rupture of membranes was significantly higher in the patients who had resulted in successful vaginal delivery than those who had failed.What are the implications are of these findings for clinical practice and/or further research? Measurement of IL-6 concentration in the amniotic fluid from vaginal canal in patients with labour might help to predict the successful vaginal delivery and shorten the time before decision of caesarean section.

Interleukin 6 as a marker of severe bacterial infection in children with sickle cell disease and fever: a case-control study

Background

Etiological diagnosis of fever in children with sickle cell disease (SCD) is often challenging. The aim of this study was to analyze the pattern of inflammatory biomarkers in SCD febrile children and controls, in order to determine predictors of severe bacterial infection (SBI).

Methods

A prospective, case–control study was carried out during 3 years, including patients younger than 18 years with SCD and fever (cases) and asymptomatic steady-state SCD children (controls). Clinical characteristics and laboratory parameters, including 10 serum proinflammatory cytokines (IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-17a, IFN-γ and TNF-α) and comparisons among study subgroups were analyzed.

Results

A total of 137 patients (79 cases and 58 controls) were included in the study; 78.5% males, median age 4.1 (1.7–7.5) years. Four cases were diagnosed with SBI, 41 viral infection (VI), 33 no proven infection (NPI) and 1 bacterial-viral coinfection (the latter excluded from the subanalyses). IL-6 was significantly higher in patients with SBI than in patients with VI or NPI (163 vs 0.7 vs 0.7 pg/ml, p < 0.001), and undetectable in all controls. The rest of the cytokines analyzed did not show any significant difference. The optimal cut-off value of IL-6 for the diagnosis of SBI was 125 pg/mL, with high PPV and NPV (PPV of 100% for a prevalence rate of 5, 10 and 15% and NPV of 98.7%, 97.3% and 95.8% for those prevalences rates, respectively).

Conclusion

We found that IL-6 (with a cut-off value of 125 pg/ml) was an optimal marker for SBI in this cohort of febrile SCD children, with high PPV and NPV. Therefore, given its rapid elevation, IL-6 may be useful to early discriminate SCD children at risk of SBI, in order to guide their management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06470-4.

A perfect storm: fetal inflammation and the developing immune system

Histologic chorioamnionitis is an inflammatory disorder of the placenta that commonly precedes preterm delivery. Preterm birth related to chorioamnionitis and fetal inflammation has been associated with a risk for serious inflammatory complications in infancy. In addition, preterm infants exposed to chorioamnionitis may be more susceptible to infection in the neonatal intensive care unit and possibly later in life. A significant body of work has established an association between chorioamnionitis and inflammatory processes. However, the potential consequences of this inflammation on postnatal immunity are less understood. In this review, we will discuss current knowledge regarding the effects of fetal exposure to inflammation on postnatal immune responses.

HMGB1-RAGE signaling pathway in pPROM

OBJECTIVE

Increased inflammation of the placenta is considered as a risk factor and a promoter of preterm premature rupture of the membranes (pPROM). High-mobility group box 1 (HMGB1) is a recently identified inflammatory cytokine, and HMGB1-RAGE signaling pathway has been associated with many pathophysiological processes. This study aims to reveal the mechanisms of HMGB1-RAGE signaling pathway in pPROM.

MATERIALS AND METHODS

The mRNA levels of relative gene of HMGB1 pathway, HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2, were analyzed by real-time PCR in placentas collected from 60 normal term women, 60 women with PROM and 60 women with pPROM. Additionally, levels of HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 protein were detected in frozen placental specimens by western blot, and the locations of HMGB1, RAGE and NF-κBp65 were evaluated in the well-characterized tissue microarray (TMA) by immunohistochemistry. ELISA was further used to detect HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 level in maternal and cord serum.

RESULTS

Compared with normal term and PROM women, we found that (1) The mRNA expressions of HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 in HMGB1-RAGE pathway of pPROM placentas were higher. (2) The protein levels of HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 in pPROM placentas were higher. (3) HMGB1 and RAGE immunoreactivity in pPROM placenta TMA were increased in the cytoplasm of syncytiotrophoblast (STB), extravillous trophoblast (EVT) and mesenchymal cells, while NF-κBp65 was enhanced in the nucleus of STB and EVT. (4) Maternal serum concentrations of HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 in pPROM group were greater. (5) Cord serum concentrations of HMGB1, RAGE, NF-κBp65, MMP-9 and MMP-2 among the 3 groups had no significant differences.

CONCLUSION

HMGB1 nuclear-cytoplasmic translocation in pPROM placenta may lead to the binding of HMGB1 to its receptor RAGE, resulting in provoking NF-κBp65 activity, and then inducing the release of MMP-9 and MMP-2, which all above activities contributed to the process of pPROM. Consequently, HMGB1-RAGE signaling pathway may be involved in the pathogenesis of pPROM.

Validation of diagnostic tests for histologic chorioamnionitis: Systematic review and meta-analysis

INTRODUCTION

The aim of this study was to determine the diagnostic performance of different diagnostic tests for histologic chorioamnionitis in patients at more than 20 weeks of gestation.

METHODS

A systematic search was carried out through MEDLINE, EMBASE, LILACS, CENTRAL and unpublished literature. Observational studies included with pregnant women (>20 weeks) with chorioamnionitis. The reference standard was the histopathological study of the placenta, umbilical cord and fetal membranes. Two independent researchers extracted data and performed a meta-analysis of diagnostic tests.

RESULTS

Twenty-nine articles were included. The studies provided evidence in the form of maternal clinical and serological tests; tests of vaginal fluid, amniotic fluid or the umbilical cord; fetal monitoring and ultrasound tests. To assess the performance of maternal serum CRP, 13 studies were included, showing a combined sensitivity of 68.7% (95%CI 58%-77%) and a combined specificity of 77.1% (95%CI 67%-84%). Maternal leukocytosis was evaluated in four publications, showing a combined sensitivity of 51% (95%CI 40%-62%) and a combined specificity of 65% (95%CI 50%-78%).

CONCLUSIONS

CRP and maternal leukocytosis, showed a low sensitivity and specificity. The sonographic evaluation of the fetal thymus is also more sensitive for the diagnosis of histologic chorioamnionitis than the fetal biophysical profile.

Clinical Significance of Interleukin-6 in the Diagnosis of Sepsis and Discriminating Sepsis Induced by Gram-negative Bacteria

BACKGROUND

To discuss the clinical significance of interleukin (IL)-6 in the differential diagnosis of sepsis and its capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria.

METHODS

A total of 379 children with sepsis were involved in this study to form the case group, and their C-reactive protein (CRP), procalcitonin (PCT) and IL-6 levels before antibiotics and after recovery were checked. Receiver operating characteristic curve was applied to evaluate the significance of CRP, PCT and IL-6 in the differential diagnosis of sepsis and their capability of differentiating the sepsis induced by Gram-negative bacteria from that induced by Gram-positive bacteria.

RESULTS

When these 3 indicators were applied to the differential diagnosis of sepsis, the area under the curve (AUC) of IL-6, PCT and CRP was 0.881, 0.877 and 0.754, respectively. The combination of IL-6 and PCT presented highest diagnostic efficiency. CRP, PCT and IL-6 levels in children with sepsis induced by Gram-negative bacteria were significantly higher than those in children with sepsis induced by Gram-positive bacteria.

CONCLUSIONS

CRP, IL-6 and PCT are applicable to the differential diagnosis of sepsis and differentiating the sepsis induced by Gram-negative bacteria from Gram-positive bacteria. Appropriate combinations of these indicators are capable of increasing differential diagnosis efficiency. These indicators can be used as markers of antibiotics usage, but whether they can be used as markers to withdraw antibiotics is still needed to be observed.

Utility of cytokines to predict neonatal sepsis

BACKGROUND

Sepsis is an important cause of neonatal morbidity and mortality worldwide. Diagnosis and treatment of neonatal sepsis relies on clinical judgment and interpretation of nonspecific laboratory tests. In a prospective cohort, we measured inflammatory cytokines as a potential biomarker for neonatal sepsis.

METHODS

Serum inflammatory cytokine levels were evaluated in the early stage of neonatal sepsis and after antimicrobial treatment. Receiver operating characteristic curves assessed the diagnostic value of cytokines. We performed multiple logistic regression analysis to characterize the role of each cytokine independently for infants with culture proven sepsis.

RESULTS

C-reactive protein, interleukin (IL)-6, IL-10 and IL-6/IL-10 levels were significantly elevated in neonatal sepsis when compared with the control group and there were 1.4 (95% confidence interval (CI): 1.2-1.5), 4.9 (95% CI: 4.6-5.1), 5.1 (95% CI: 4.5-5.6), and 10.2 (95% CI: 9.2-11.1) fold greater odds, respectively, to predict neonatal sepsis when increased. After effective treatment, median IL-6 (pretreatment value: 263.0 pg/ml and post-treatment value: 7.4 pg/ml) and IL-6/IL-10 levels (pretreatment value: 16.6 and post-treatment value: 1.4) significantly decreased. The areas under the curve for IL-6, IL-10, IL-6/IL-10 and C-reactive protein for differential diagnosis were 0.98, 0.82, 0.90, and 0.88, respectively.

CONCLUSION

IL-6 and IL-6/IL-10 outperformed C-reactive protein to diagnose neonatal sepsis. Of the cytokines studied, IL-6 was the most sensitive, whereas IL-6/IL-10 was the most specific predictor of neonatal sepsis.

Neutrophil extracellular traps in acute chorioamnionitis: A mechanism of host defense

PROBLEM

Neutrophil extracellular traps (NETs) were recently described as a mechanism for microbial killing in the amniotic cavity of women with intra-amniotic infection. Such a clinical condition can result in acute chorioamnionitis, a placental lesion characterized by the infiltration of maternal neutrophils in the chorioamniotic membranes. Herein, we investigated whether these infiltrating neutrophils form NETs in the chorioamniotic membranes from women who underwent spontaneous term or preterm labor with acute chorioamnionitis.

METHOD OF STUDY

Chorioamniotic membrane samples were collected from women who underwent spontaneous term or preterm labor with acute chorioamnionitis (n=10 each). Controls included chorioamniotic membrane samples from women who delivered at term or preterm with or without labor in the absence of acute chorioamnionitis (n=10 each). NETs were visualized and semiquantified in the chorioamniotic membranes by using antibodies against neutrophil elastase and histone H3 in combination with DAPI staining.

RESULTS

Neutrophil extracellular traps were abundant in the chorioamniotic membranes from women who underwent spontaneous term or preterm labor with acute chorioamnionitis. NETs were rarely found, or not visualized at all, in the chorioamniotic membranes from women who delivered at term or preterm with or without labor in the absence of acute chorioamnionitis.

CONCLUSION

Neutrophil extracellular traps are abundant in the chorioamniotic membranes from women who underwent spontaneous term or preterm labor with acute chorioamnionitis. These findings suggest that chorioamniotic neutrophils can form NETs as a mechanism of host defense against infection or danger signals.

Utility of cytokine, adhesion molecule and acute phase proteins in early diagnosis of neonatal sepsis

Background and Aim:

Neonatal infection, including bacterial sepsis, is a major health care issue with an annual global mortality in excess of one million lives. Therefore, this study aimed to evaluate the potential diagnostic value of C-reactive protein (CRP), E-selectin, procalcitonin (PCT), interleukins-6 (IL-6), and tumor necrosis factor-α (TNF-α) both independently and in combination for the diagnosis of neonatal sepsis in its earliest stages.

Materials and Methods:

A total of 320 subjects were included in this study. A prospective cross-sectional study was conducted among neonates admitted to Neonatal Intensive Care Unit at King Abdulaziz Medical City, Riyadh, KSA during January 2013 to August 2015, the study based on three study groups categorized according to clinical symptoms and blood culture result. Study groups include healthy control neonates (n = 80), clinical sepsis (CS) group (n = 80) with clinical signs of sepsis but their blood culture was negative, and sepsis group with clinical signs of sepsis and their blood culture was positive.

Results:

The study observed significant difference in plasma levels of CRP, IL-6, TNF-α, E-selectin, and PCT in patients group when compared with control group (P < 0.001). Furthermore, the levels are significantly different between patient groups including CS and neonatal sepsis group. Moreover, result observed significant difference in CRP and IL-6 in early onset sepsis (EOS) when compared with late onset sepsis (LOS) neonates (P < 0.001 and 0.01), respectively, while there were no significant difference in TNF-α, E-selectin, and PCT between EOS and LOS (P = 0.44, 0.27 and 0.24), respectively. Regarding biomarkers accuracy, the result showed that CRP has the best diagnostic accuracy with cutoff value of 3.6 ng/ml (sensitivity 78% and specificity of 70%). The best combination is shown with CRP and IL-6 in which sensitivity increased to 89% and specificity to 79%.

Conclusion:

It was concluded that infected new-born babies have a higher E-selectin, PCT, IL-6, TNF-α, and CRP compared with the neonates with CS and control. IL-6, TNF-α, and CRP should be measured in combination for mare diagnostic accuracy in neonatal sepsis. Likewise, PCT should be investigated as a part of sepsis screening for all suspected neonates.

A Role for the Inflammasome in Spontaneous Labor at Term with Acute Histologic Chorioamnionitis

Inflammasomes are cytosolic signaling platforms that regulate the activation of caspase (CASP)-1, which induces the maturation of interleukin (IL)-1β and IL-18. Herein, we determined whether the chorioamniotic membranes from women in spontaneous labor at term with acute histologic chorioamnionitis express major inflammasome components and whether these changes are associated with the activation of CASP-1 and CASP-4 and the release of mature IL-1β and IL-18. When comparing the chorioamniotic membranes from women in spontaneous labor at term with acute histologic chorioamnionitis to those without this placental lesion, we found that (1) the messenger RNA (mRNA) abundance of NLR family pyrin domain containing 3 ( NLRP3), NLR family CARD domain containing 4 ( NLRC4), absent in melanoma 2 ( AIM2), and nucleotide binding oligomerization domain 2 ( NOD2) was higher; (2) the NLRP3 and NLRC4 protein quantities were increased; (3) the mRNA and protein expressions of CASP-1 and its active forms were greater; (4) CASP-4 was increased at the mRNA level only; (5) the mRNA and protein expressions of IL-1β and its mature form were higher; and (6) a modest increase in the total protein concentration and abundance of the mature form of IL-18 was observed. In vitro incubation of the chorioamniotic membranes with the CASP-1 inhibitor, VX765, decreased the release of endotoxin-induced IL-1β and IL-18 (2-fold) but not IL-6 or tumor necrosis factor α. In conclusion, spontaneous labor at term with acute histologic chorioamnionitis is characterized by an upregulation of inflammasome components which, in turn, may participate in the activation of CASP-1 and lead to the release of mature IL-1β by the chorioamniotic membranes. These results support a role for the inflammasome in the mechanisms responsible for spontaneous labor at term with acute histologic chorioamnionitis.

Accuracy of several maternal seric markers for predicting histological chorioamnionitis after preterm premature rupture of membranes: a prospective and multicentric study

OBJECTIVE

To assess and compare several maternal seric markers for the prediction of histological chorioamnionitis (HCA) after preterm premature rupture of membranes (PPROM). Study design A prospective and multicentric observational study was undertaken, including six French tertiary referral centres. Pregnant women over 18 years, with PPROM between 22+0 and 36+6 WG were enrolled. A blood sample was obtained before delivery and analysed for C-Reactive Protein (CRP), InterCellular Adhesion Molecule-1 (ICAM-1), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Matrix-Metalloproteinase 8 and 9 (MMP-8, MMP-9), Triggering receptor on myeloid cells (TREM-1), and Human Neutrophile Peptides (HNP). HCA was determined by histological examination distinguishing maternal from fetal inflammatory response. Placental analyses and biological assays were performed in duplicate. Comparison of maternal seric markers levels in women with or vs. without HCA was performed, using a non-parametric Receiver Operating Characteristic.

RESULTS

295 women were kept for analysis. The prevalence of HCA was 42.7% (126/295). The concentrations of MMP-8, MMP-9, HNP and CRP were higher in HCA vs. the non-HCA group (P<0.05) whereas the concentrations of ICAM- 1, IL-6, IL-8 were not different (P>0.05). The ROC curve with the largest AUC was for CRP (AUC; 0.70; 95% CI; 0.64-0.77) and it was significantly higher than those for MMP-8, MMP-9, or HNP (P<0.03).

CONCLUSION

CRP was the best maternal marker for predicting HCA in women with PPROM.

Maternal obesity, diabetes mellitus and cord blood biomarkers in large-for-gestational age infants

Infants born large-for-gestational age (LGA) are at risk for early childhood obesity. The aims of this study were to investigate factors associated with LGA status and their relationship to inflammatory biomarkers that have been implicated in the LGA infant at birth. Included were 364 mother-infant pairs enrolled as part of an ongoing longitudinal cohort study of infant birth weight being conducted at Boston Medical Center (BMC). LGA was defined as birth weight (BW) ≥90(th) percentile of the reference population at BMC (N=45). Appropriate-for-gestational age (AGA) was defined as BW<90(th) and >10(th) percentile (N=319). Cord blood IL-6, IL-8, TNF-alpha and RANTES levels were analyzed from a larger panel of immune biomarkers measured using multiplex immunoassay. Multivariate regression models were used to determine the associations between LGA status, maternal BMI and diabetes (DM), which included either gestational or type 2 diabetes (T2DM), and cord blood biomarkers, with adjustment for important demographic and clinical variables. Maternal pre-pregnancy BMI within the obesity range (≥30 kg/m(2)), as well as DM, were each associated with increased risk of LGA (OR=2.64, 95%CI 1.31-6.20; OR=5.58, 95%CI 2.06-15.13, respectively). Among the 4 biomarkers, only RANTES (regulated on activation, normal T cell express and secreted upon uptake), which is a chemokine secreted by white adipose tissue, was significantly increased in LGA infants (beta-coefficient=0.37; 95% CI: 0.09, 0.65; P<0.01). This association remained essentially unchanged after adjustment for maternal DM and BMI (beta-coefficient=0.37; 95% CI: 0.08, 0.65; P=0.01). Ponderal index (PI=BW×100/length(3)) was also positively correlated with RANTES. Cord blood RANTES is selectively elevated with fetal macrosomia, independent of maternal factors. Further investigation of RANTES as a marker of LGA and future childhood health is warranted.

Clinical chorioamnionitis at term VI: acute chorioamnionitis and funisitis according to the presence or absence of microorganisms and inflammation in the amniotic cavity

OBJECTIVE

Neonates born to mothers with clinical chorioamnionitis at term are at an increased risk of infection. Acute subchorionitis, chorioamnionitis, and funisitis are considered placental histologic features consistent with acute inflammation according to the Society for Pediatric Pathology. The objectives of this study were to examine the performance of placental histologic features in the identification of: 1) microbial-associated intra-amniotic inflammation (intra-amniotic infection); and 2) fetal inflammatory response syndrome (FIRS).

METHODS

This retrospective cohort study included women with the diagnosis of clinical chorioamnionitis at term (n=45), who underwent an amniocentesis to determine: 1) the presence of microorganisms using both cultivation and molecular biologic techniques [polymerase chain reaction (PCR) with broad range primers]; and 2) interleukin (IL)-6 concentrations by enzyme-linked immunosorbent assay (ELISA). The diagnostic performance (sensitivity, specificity, accuracy, and likelihood ratios) of placental histologic features consistent with acute inflammation was determined for the identification of microbial-associated intra-amniotic inflammation and FIRS.

RESULTS

1) The presence of acute histologic chorioamnionitis and funisitis was associated with the presence of proven intra-amniotic infection assessed by amniotic fluid analysis; 2) funisitis was also associated with the presence of FIRS; 3) the negative predictive value of acute funisitis ≥stage 2 for the identification of neonates born to mothers with intra-amniotic infection was <50%, and therefore, suboptimal to exclude fetal exposure to bacteria in the amniotic cavity; and 4) acute funisitis ≥stage 2 had a negative predictive value of 86.8% for the identification of FIRS in a population with a prevalence of 20%.

CONCLUSION

Acute histologic chorioamnionitis and funisitis are associated with intra-amniotic infection and the presence of FIRS. However, current pathologic methods have limitations in the identification of the fetus exposed to microorganisms present in the amniotic cavity. Further studies are thus required to determine whether molecular markers can enhance the performance of placental pathology in the identification of neonates at risk for neonatal sepsis.

Clinical chorioamnionitis at term V: umbilical cord plasma cytokine profile in the context of a systemic maternal inflammatory response

OBJECTIVE

Microbial invasion of the fetus due to intra-amniotic infection can lead to a systemic inflammatory response characterized by elevated concentrations of cytokines in the umbilical cord plasma/serum. Clinical chorioamnionitis represents the maternal syndrome often associated with intra-amniotic infection, although other causes of this syndrome have been recently described. The objective of this study was to characterize the umbilical cord plasma cytokine profile in neonates born to mothers with clinical chorioamnionitis at term, according to the presence or absence of bacteria and/or intra-amniotic inflammation.

MATERIALS AND METHODS

A cross-sectional study was conducted, including patients with clinical chorioamnionitis at term (n=38; cases) and those with spontaneous term labor without clinical chorioamnionitis (n=77; controls). Women with clinical chorioamnionitis were classified according to the results of amniotic fluid culture, broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) and amniotic fluid interleukin (IL)-6 concentration into three groups: 1) no intra-amniotic inflammation; 2) intra-amniotic inflammation without detectable microorganisms; or 3) microbial-associated intra-amniotic inflammation. A fetal inflammatory response syndrome (FIRS) was defined as an umbilical cord plasma IL-6 concentration >11 pg/mL. The umbilical cord plasma concentrations of 29 cytokines were determined with sensitive and specific V-PLEX immunoassays. Nonparametric statistical methods were used for analysis, adjusting for a false discovery rate of 5%.

RESULTS

1) Neonates born to mothers with clinical chorioamnionitis at term (considered in toto) had significantly higher median umbilical cord plasma concentrations of IL-6, IL-12p70, IL-16, IL-13, IL-4, IL-10 and IL-8, but significantly lower interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF)-α concentrations than neonates born to mothers with spontaneous term labor without clinical chorioamnionitis; 2) neonates born to mothers with clinical chorioamnionitis at term but without intra-amniotic inflammation had higher concentrations of IL-6, IL-12p70, IL-13, IL-4, IL-5, and IL-8, but lower IFN-γ, than neonates not exposed to clinical chorioamnionitis, suggesting that maternal fever in the absence of intra-amniotic inflammation leads to a change in the fetal cytokine network; 3) there were significant, positive correlations between maternal and umbilical cord plasma IL-6 and IL-8 concentrations (IL-6: Spearman correlation=0.53; P<0.001; IL-8: Spearman correlation=0.42; P<0.001), consistent with placental transfer of cytokines; 4) an elevated fetal plasma IL-6 (>11 pg/mL), the diagnostic criterion for FIRS, was present in 21% of cases (8/38), and all these neonates were born to mothers with proven intra-amniotic infection; and 5) FIRS was associated with a high concentration of umbilical cord plasma IL-8, IL-10 and monocyte chemoattractant protein (MCP)-1.

CONCLUSIONS

Neonates born to mothers with clinical chorioamnionitis at term had higher concentrations of umbilical cord plasma cytokines than those born to mothers without clinical chorioamnionitis. Even neonates exposed to clinical chorioamnionitis but not to intra-amniotic inflammation had elevated concentrations of multiple cytokines, suggesting that intrapartum fever alters the fetal immune response.

Clinical and prognostic value of combined measurement of cytokines and vascular cell adhesion molecule-1 in premature rupture of membranes

OBJECTIVE

To evaluate whether levels of interleukin 6 (IL-6), interleukin 8 (IL-8), and vascular cell adhesion molecule-1 (VCAM-1) in women with premature rupture of membranes (PROM) differ from those in women without PROM.

METHODS

An observational study of full-term primiparous pregnant women with PROM (PROM group) and those undergoing elective cesarean delivery (control group) was performed at a center in Yangzhou, China, between January 2003 and July 2006. IL-6, IL-8, and VCAM-1 levels were measured in maternal blood, cord blood, and amniotic fluid. A pathologic examination of fetal membranes was conducted.

RESULTS

The IL-6, IL-8, and VCAM-1 levels in maternal serum, amniotic fluid, and cord blood were significantly higher in the PROM group (n=58) than in the control group (n=38; P<0.05 for all comparisons). In the PROM group, the levels increased with duration of membrane rupture (P<0.05 for all). Women with chorioamnionitis had significantly higher levels than women without chorioamnionitis (P<0.05 for all), and women with PROM whose newborns had low Apgar score (≤7) had higher levels than those whose newborns had a higher Apgar score (P<0.05 for all).

CONCLUSION

Combined measurements of IL-6, IL-8, and VCAM-1 might help to improve early diagnosis of PROM and chorioamnionitis, and to evaluate the prognosis of newborns.

Neonatal sepsis and inflammatory mediators

Neonatal sepsis is a major cause of morbidity and mortality and its signs and symptoms are nonspecific, which makes the diagnosis difficult. The routinely used laboratory tests are not effective methods of analysis, as they are extremely nonspecific and often cause inappropriate use of antibiotics. Sepsis is the result of an infection associated with a systemic inflammatory response with production and release of a wide range of inflammatory mediators. Cytokines are potent inflammatory mediators and their serum levels are increased during infections, so changes from other inflammatory effector molecules may occur. Although proinflammatory and anti-inflammatory cytokines have been identified as probable markers of neonatal infection, in order to characterize the inflammatory response during sepsis, it is necessary to analyze a panel of cytokines and not only the measurement of individual cytokines. Measurements of inflammatory mediators bring new options for diagnosing and following up neonatal sepsis, thus enabling early treatment and, as a result, increased neonatal survival. By taking into account the magnitude of neonatal sepsis, the aim of this review is to address the role of cytokines in the pathogenesis of neonatal sepsis and its value as a diagnostic criterion.

Reference values for interleukin-6 and interleukin-8 in cord blood of healthy term neonates and their association with stress-related perinatal factors

BACKGROUND

Automated interleukin assays are promising diagnostic aids for early-onset neonatal sepsis, however, reference values for healthy term neonates are incompletely known. The goal of this study is to determine reference values for interleukin-6 (IL-6) and interleukin-8 (IL-8) in cord blood of healthy term neonates.

METHODS AND FINDINGS

Women were recruited from April 2012 to August 2012. IL-6 and IL-8 levels were measured using an automated immunometric assay (Immulite) in cord blood of 93 healthy term newborns, 60 of them were born via vaginal delivery and 33 by elective caesarean section (ECS). A mean value for IL-8 of 8.1 ± 3.0 pg/mL was found in cord blood of healthy term neonates, which apply to both vaginal delivery and ECS. Regarding IL-6, two values apply. For vaginal delivery, a median value of 3.3 pg/mL (range, <2 to 9.53 pg/mL) was found, while for ECS, a median value of <2 pg/mL (range, <2 to 48 pg/mL) applies.

CONCLUSIONS

We propose a reference value of <14.1 pg/mL for IL-8 (mean + 2SD), applying to vaginally delivered and ECS-delivered healthy term newborns. From a clinical point of view, we also propose one reference value for IL-6 to be applied to vaginally delivered and ECS-delivered healthy term newborns, which is <10.2 pg/mL (97.5th percentile total group). These values have to be validated in larger cohorts of neonates, inclusive of those with and without early-onset neonatal sepsis.

Changes in maternal blood inflammatory markers as a predictor of chorioamnionitis: a prospective multicenter study

PROBLEM

To evaluate the inflammatory pattern in maternal circulation from women with preterm premature rupture of membranes (PPROM) considering the occurrence of histologically confirmed chorioamnionitis (HCA).

METHOD OF STUDY

A prospective study was conducted in 121 women with PPROM between 24 and 34 + 0 weeks of gestation. Association between white blood cells (WBC) count, plasma CRP, IL-6, MCP-1 and IP-10 levels, and HCA was assessed.

RESULTS

The rate of HCA was 44.7% (54/121). During the 5 days preceding delivery, median CRP, WBC, and IL-6 levels were significantly higher in the HCA than in no-HCA group (P < 0.001). Variations in IL-6, IP-10 levels, during the 24-72 hr before delivery, were predictors of the occurrence of HCA, but the diagnostic accuracy was low [Receiver Operating Characterictic (ROC) curve, area under the curve (AUC) = 0.56].

CONCLUSION

An increase in IL-6, CRP, IP-10 maternal plasma levels was confirmed in PPROM women with HCA. Longitudinal follow-up of these markers did not add valuable information regarding HCA.

Pentraxin 3 concentrations of the mothers with preterm premature rupture of membranes and their neonates, and early neonatal outcome

BACKGROUND

Pentraxin 3 (PTX3) is an acute phase reactant which has been used to detect intra-amniotic infections (IAI) in pregnancy, but the prognostic value of PTX3 concentrations on neonates has not been studied. We aimed to investigate the relationship between maternal PTX3-neonatal PTX3 concentrations and early neonatal outcome.

METHODS

The mothers diagnosed with preterm prelabor rupture of membranes (PPROM) (n = 28) and their preterm infants (n = 28) were included in the study. PTX3 concentrations were studied in plasma in the maternal peripheral blood and umbilical/peripheral vein in the neonates. The relationship between the mPTX3-nPTX3 concentrations and neonatal outcome were investigated using non-parametric tests and binary logistic regression analysis.

RESULTS

The mean mPTX3 concentration was 10.35 ± 7.82 μg/L. Ten (35.7%) of all mothers were within the normal range and 18 (64.3%) in high percentile (≥ 97.5 percentile). There was no relation between mPTX3 concentrations and clinical or histologic chorioamnionitis, latency of PPROM, and early neonatal outcome. Mean nPTX3 concentrations was 9.18 ± 7.83 μg/L and high nPTX3 concentrations were detected in five (17.8%) neonates. nPTX3 concentrations were inversely correlated with gestational age and correlated with rate of intraventricular hemorrhage (IVH) and mortality. Neonates with high nPTX3 concentrations also have lowered APGAR scores, increased rate of respiratory distress syndrome, clinical sepsis, IVH, necrotizing enterocolitis and prolonged NICU stay.

CONCLUSION

High PTX3 concentrations of the newborns are associated with some worsened early neonatal outcome including lower gestational age at delivery, increased rate of IVH and mortality. Maternal PTX3 concentrations are not an adequate marker in defining clinical or histologic chorioamnionitis and early neonatal outcome.

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.

Comparative assessment of cytokines and other inflammatory markers for the early diagnosis of neonatal sepsis-a case control study

OBJECTIVE

Cytokines (IL-6, IL-8 and TNF-α), sCD163, and C-reactive protein were serially measured in an attempt to identify a set of tests which can reliably confirm or refute the diagnosis of neonatal sepsis at an early stage.

METHODS

One hundred neonates suspected to have sepsis on clinical grounds and who met the inclusion criteria were enrolled for the study. Based on the positive or negative blood culture reports they were classified as infected (n=50) and non-infected (n=50) neonates respectively. Fifty healthy neonates without any signs of sepsis were also included in the study as control group. The initial blood sample was taken on day 0 (at the time of sepsis evaluation) and two further samples were taken on days 1 and 2 for monitoring the clinical progress and response to treatment. In the control group the cord blood and 48 hours venous sample was collected. Plasma CRP (ng/ml), IL-6 (pg/ml), IL-8 (pg/ml), TNF-α (ng/ml) and sCD163 (ng/ml) were determined by double antibody method Enzyme Linked Immunosorbent Assay in all the three blood samples.

RESULTS

The cut of levels for CRP at >19,689 ng/ml had a sensitivity of 68%, specificity of 92%, for IL-6 at >95.32 pg/ml had a sensitivity of 54%, specificity of 96%, for IL-8 at >70.86 pg/ml had a sensitivity of 78%, specificity of 70%, for sCD163 at >896.78 ng/ml had a sensitivity of 100%, specificity of 88% for the diagnosis of infection before antibiotics. TNF-α levels of >12.6 ng/ml showed 100% sensitivity and 72% specificity for the diagnosis of inflammation.

CONCLUSION

The most powerful predictor to differentiate between the non-infected and infected neonates before antibiotics was sCD163. The most powerful indicator for evaluation of prognosis is IL-6. sCD163 can be used alone to screen for sepsis in neonates before the results of blood culture are received.

Temporal trends in chorioamnionitis by maternal race/ethnicity and gestational age (1995-2010)

Objective. To characterize trends in chorioamnionitis (CAM) by maternal race/ethnicity and gestational age. Study Design. We examined trends in CAM from 1995–2010 among singleton births in all Kaiser Permanente Southern California hospitals (n = 471,821). Data were extracted from Perinatal Service System and clinical utilization records. Gestational age- and race/ethnicity-specific biannual diagnosis rates were estimated using the Poisson regression after adjusting for potential confounding factors. Results. Overall diagnosis rates of CAM increased from 2.7% in 1995-1996 to 6.0% in 2009-2010 with a relative increase of 126% (95% confidence intervals [CI] 113%–149%). From 1995-1996 to 2009-2010, CAM increased among the Whites (1.8% to 4.3%, P-value for trend <.001), Blacks (2.2% to 3.7%, P-value for trend <.001), Hispanics (2.4% to 5.8%, P-value for trend <.001), and Asian/Pacific Islanders (3.6% to 9.0%, P-value for trend <.001). The adjusted relative percentage change in CAM from 1995-1996 to 2009-2010 was for Whites [preterm 21% (9%–78%), term 138% (108%–173%)], for Blacks [preterm 24% (−9%–81%), term 62% (30%–101%)], for Hispanics [preterm 31% (3%–66%), term 135% (114%–159%)], and for Asian/Pacific Islanders [preterm 44% (9%–127%), term 145% (109%–188%)]. Conclusion. The findings suggest that CAM diagnosis rate has increased for all race/ethnic groups. This increase is primarily due to increased diagnosis at term gestation.

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.

Umbilical blood biomarkers for predicting early-onset neonatal sepsis

BACKGROUND

Since the 1990s, finding the most efficient markers or combinations as predictors of early-onset neonatal sepsis has been the hot topic of studies. But there is no review of such biomarkers detected in umbilical blood at birth. By comparing clinical values of common inflammatory markers detected in cord blood shortly after birth, in this study we tried to find the most performing one or the most efficient combination that might be potentially used in birth room, as the earliest predictor of early-onset neonatal sepsis.

DATA SOURCES

We searched PubMed and Elsevier's Web of Science for studies evaluating cord blood inflammatory markers in relation to early-onset neonatal sepsis.

RESULTS

Among C-reactive protein (CRP), procalcitonin (PCT), IL-6, IL-8, TNF-α and IL-1β, none of them could be used individually to establish or exclude the diagnosis of early-onset neonatal sepsis, but PCT, IL-6 and IL-8 have great superiority to CRP, TNF-α and IL-1β. When combined with other hematological markers and clinical observation, the clinical reliability of PCT, IL-6 and IL-8 could be improved. Prolonging the sample collection time window seems to have a positive effect on the clinical utility of IL-6 and IL-8.

CONCLUSIONS

More researches focusing on the combination of different umbilical cord biomarkers in different clinical settings are needed to achieve clearer conclusions. Multi-center, large-sized analysis, especially examining groups of cytokines, is also expected.

Color of meconium and interleukin-6

OBJECTIVE

To test the hypothesis that the color of meconial fluid is associated with inflammatory biomarkers, by determining C-reactive protein (CRP) and Interleukin-6 (IL-6) in serum from the umbilical cord.

METHODS

In this prospective study, the authors selected 30 newborns with meconium-stained amniotic fluid (MSAF): 14 with green/brown 656 R color and 16 with brown/cinnamon 654 R color, and 20 newborns which showed clear amniotic fluid without MSAF (non-MSAF); all newborns were from mothers without risk factors for neonatal sepsis.

RESULTS

IL-6 concentration from umbilical cord blood, [median of 12.9 pg/mL (interquartile range {IQR} 8.7-31.0)] of MSAF-green/brown 656 R increased significantly (p < 0.05) when compared with IL-6 concentration, [median of 9.2 pg/mL (IQR 7.2-12.2)] of newborns with clear amniotic fluid and without meconium. CRP from MSAF-green/brown 656 R was median of 0.5 mg/mL (IQR 0.0-2.7), and median of 1.0 mg/mL (IQR 0.0-5.5) from clear amniotic fluid, without meconium.

CONCLUSIONS

Significant association was found between MSAF-green/brown 656 R and increase in IL-6, with normal CRP values.

[The role of infection in preterm birth]

Intrauterine infection could be responsible for 25% up to 40% of preterm births. This relationship was initially demonstrated using animal models, inducing their abortion by injecting bacteria or endotoxins. In human research, examination of amniocentesis fluid showed the anteriority of infection over labor induction, and the existence of a subclinical latency phase between these two phenomena. The ascending route is preponderant, and four stages can be distinguished: cervical and vaginal infection, chorio-decidual infection, intra-amniotic infection, fetal infection. The intrauterine infection is very frequent in case of early preterm birth (<30 WG). It is associated with an increase of neurological and pulmonary morbidity. Most commonly found bacterial species are mycoplasma species, but also Escherichia coli, Gardnerella vaginalis and streptococcus B. Several markers of the infection have been studied: a maternal leukocytosis>15,000/mm(3) or a C-Reactive Protein (CRP)>20mg/l, an increase of fibronectin and/or IL-6 cervical, a short cervical length especially before 32 WG, a leukocytosis of the amniotic fluid, and/or high interleukin concentrations. The main marker used for the newborn is the CRP, but other markers can also be used for an early diagnosis of an infection, especially interleukin 6.

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.

Chorioamnionitis--a complex pathophysiologic syndrome

Chorioamnionitis, inflammation of the amniochorionic membrane (fetal membranes) is a very common disease but a complex syndrome associated with pregnancy. It presents a clinical impasse due to lack of knowledge of specific etiologies associated with this condition making confident clinical interventions difficult. Recent reports provide insight into genetic, epigenetic, behavioral, psychosocial, molecular and pathophysiological factors that are associated with chorioamnionitis. However, a coordinated approach in understanding causality and lack of early indicators (clinical and biomarkers) has hampered gaining knowledge about the disease status preventing proper intervention. Several reviews have provided in-depth analysis of the histologic and clinical evidence associated with chorioamnionitis. In this review, we provide a novel perspective on chorioamnionitis based on recent evidences from scientific literature on inflammation, apoptosis and genetics.

Cord blood biomarkers of the fetal inflammatory response

OBJECTIVE

In current, neonatal practice, clinical signs of intrauterine infection (IUI) are often non-specific. From a large panel of immune biomarkers, we seek to identify cord blood markers that are most strongly associated with the fetal inflammatory response (FIR), a specific placental lesion associated with serious neonatal complications.

METHODS

We used multiplex immunoassay to measure 27 biomarkers, selected as part of an NIH-funded study of preterm birth, according to gestational age (GA) and extent of placental inflammation: involvement of chorion, amnion, decidua (maternal inflammatory response, MIR); extension to umbilical cord or chorionic plate (FIR). We used false-discovery rate (FDR < 5%, P < 0.001) to account for multiple comparisons.

RESULTS

Among 506 births (GA 23-42 weeks), IL-1 beta increased with FIR among preterm subgroups (P = 0.0001 for <32 weeks; P = 0.0009 for 33-36 weeks). IL-6 and IL-8 increased with FIR among preterm and full-term infants (P < 0.0001). P-trend for IL-6 and IL-8 with MIR versus FIR was <0.0001. Comparison with respect to clinical IUI yielded persistent elevation with FIR even when clinical signs were absent. The remaining 24 markers were not significantly associated.

CONCLUSION

We conclude that among 27 cord blood biomarkers, IL-1 beta, IL-6 and IL-8 are selectively associated with FIR. These markers may be clinically useful indicators of extensive IUI associated with poor neonatal outcome.

Interleukin-6 polymorphism is associated with chorioamnionitis and neonatal infections in preterm infants

OBJECTIVES

To evaluate whether genotypes of interleukin (IL)-6 gene promoter positions -174 and -572 are associated with histologic chorioamnionitis and neonatal inflammatory disease in preterm infants.

STUDY DESIGN

DNA from very low birth weight or very preterm infants (n = 107) was genotyped for IL-6-174 and -572 polymorphisms (GG/GC/CC). The placentas were analyzed for histological inflammatory findings. Data on neonatal inflammatory diseases, including chronic lung disease (CLD), necrotizing enterocolitis (NEC), and septicemia, were collected using the definitions of the Vermont Oxford Network database.

RESULTS

In univariate analyses, the IL-6-174 GG genotype was associated with a higher incidence of histologic chorioamnionitis. In multivariate analyses, the -174 GG and -572 GC genotypes were correlated with histologic chorioamnionitis (P = .039 and .009, respectively). Gestational age was not associated with genotype polymorphisms. IL-6-174 genotypes were not associated with CLD and/or NEC, but the CC genotype was correlated with septicemia in both univariate and multivariate analyses (P = .027). IL-6-572 genotypes were not associated with neonatal inflammatory disease.

CONCLUSIONS

The IL-6-174 GG and -572 GC genotypes were associated with a higher incidence of histologic chorioamnionitis, and the IL-6-174 CC genotype was associated with septicemia in preterm infants. These findings suggest that the genetic composition of the IL-6 promoter area plays a significant role in the pathogenesis of chorioamnionitis and neonatal infections.

MATERNAL TEMPERATURE IN LABOUR

In this review, we are concerned primarily with pyrexia (hyperthermia; increased maternal temperature in labour) as hypothermia is rare and usually iatrogenic (as in hypothermia for cardiac bypass surgery). We start by reviewing the factors determining maternal temperature, and how it can be measured. We move on to the effects of the commonest cause of maternal pyrexia in labour in modern obstetric practice in developed countries, epidural anaesthesia. We then discuss the most feared cause of maternal pyrexia in labour, chorioamnionitis.