Clinical utility of gastric fluid cytokine levels in preterm infants for predicting histological chorioamnionitis.

BACKGROUND: The risk of various complications, such as neonatal death, early onset sepsis, and chronic lung disease, is increased in infants born to mothers with chorioamnionitis (CAM). However, predicting the diagnosis of histological CAM (hCAM) in the early postnatal period is challenging for clinicians due to pathological considerations. Therefore, an early diagnostic tool for hCAM is needed. Gastric fluid at birth is considered a suitable biomarker for predicting the intrauterine environment because most of its components are from amniotic fluid, and the sampling technique is less invasive. This study aimed to evaluate the clinical utility of cytokines in the gastric fluid of preterm infants at birth as predictors of hCAM. METHODS: We retrieved gastric fluid and serum from 21 preterm infants with a gestational age of ≤ 32 weeks within 1 h after birth and used cytometric bead array to measure the concentrations of interleukin (IL)-2, IL-4, IL-6, IL-10, tumor necrosis factor-alpha, and interferon-gamma. We compared the cytokine concentrations in the gastric fluid and serum of the preterm infants born to mothers with or without hCAM. RESULTS: The gastric fluid, serum IL-6, and serum IL-10 concentrations were significantly higher in the hCAM group than that in the non-hCAM group. The best cutoff values for predicting hCAM was > 2,855 pg/mL and > 315 pg/mL for IL-6 in the gastric fluid and serum, respectively. Receiver operating characteristic curves showed that gastric fluid IL-6 concentrations correlated more strongly with the presence of hCAM than serum IL-6 concentrations. CONCLUSION: IL-6 in the gastric fluid at birth may be a more promising biomarker for predicting the presence of hCAM than that in serum. IL-6 concentration analysis in the gastric fluid at birth might help to diagnose hCAM immediately after birth and improve the prognosis of preterm infants.

Syndecan-1 Level, a Marker of Endothelial Glycocalyx Degradation, Is Associated With Fetal Exposure to Chorioamnionitis and Is a Potential Biomarker for Early-Onset Neonatal Sepsis.

The goal of this investigation was to identify the association between Syndecan-1 (S1) serum levels in preterm newborns exposed to chorioamnionitis (CA) in utero and the potential of S1 as a biomarker of early-onset neonatal sepsis. A cohort of preterm newborns born <33 weeks gestational age was recruited. Within 48 hours of birth, 0.5 mL of blood was drawn to obtain S1 levels, measured via ELISA. Placentas were examined and classified as having (1) no CA, (2) CA without umbilical cord involvement, or (3) CA with inflammation of the umbilical cord (funisitis). S1 levels were compared between preterm newborns without exposure to CA verus newborns with exposure to CA (including with and without funisitis). Preterm newborns exposed to CA were found to have significantly elevated S1 levels compared to those unexposed. Although S1 levels could not differentiate fetal exposure to CA from exposure to CA with funisitis, the combined CA groups had significantly higher S1 levels compared to those not exposed to CA. S1 level has the potential to become a clinically useful biomarker that could assist in the management of mothers and preterm newborns with CA and funisitis. Furthermore, S1 level could aid in the diagnosis and treatment of early-onset neonatal sepsis.

Angiogenic imbalance in pregnancies with preterm prelabor rupture of membranes between 34 and 37 weeks of gestation.

INTRODUCTION: This study aimed to identify whether microbial invasion of the amniotic cavity and/or intra-amniotic inflammation in women with late preterm prelabor rupture of membranes (PPROM) was associated with changes in concentrations of soluble fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF) and its ratio in maternal serum, and whether placental features consistent with maternal vascular malperfusion further affect their concentrations. MATERIAL AND METHODS: This historical study included 154 women with singleton pregnancies complicated by PPROM between gestational ages 34+0 and 36+6 weeks. Transabdominal amniocentesis was performed as part of standard clinical management to evaluate the intra-amniotic environment. Women were categorized into two subgroups based on the presence of microorganisms and/or their nucleic acids in amniotic fluid (determined by culturing and molecular biology method) and intra-amniotic inflammation (by amniotic fluid interleukin-6 concentration evaluation): (1) those with the presence of microorganisms and/or inflammation (at least one present) and (2) those with negative amniotic fluid for infection/inflammation (absence of both). Concentrations of sFlt-1 and PlGF were assessed using the Elecsys® sFlt-1 and Elecsys® PlGF immunoassays and converted into multiples of medians. RESULTS: Women with the presence of microorganisms and/or inflammation in amniotic fluid had lower serum concentrations of sFlt-1 and sFlt-1/PlGF ratios and higher concentrations of PlGF compared with those with negative amniotic fluid. (sFlt-1: presence: median 1.0 multiples of the median (MoM), vs negative: median: 1.5 MoM, P = 0.003; PlGF: presence: median 0.7 MoM, vs negative: median 0.4 MoM, P = 0.02; sFlt-1/PlGF: presence: median 8.9 vs negative 25.0, P = 0.001). Higher serum concentrations of sFlt-1 and sFlt-1/PlGF ratios as well as lower concentrations of PlGF were found in the subsets of women with maternal vascular malperfusion than in those without maternal vascular malperfusion. CONCLUSIONS: Among women experiencing late PPROM, angiogenic imbalance in maternal serum is primarily observed in those without both microbial invasion of the amniotic cavity and intra-amniotic inflammation. Additionally, there is an association between angiogenic imbalance and the presence of maternal vascular malperfusion.

Predictive potential of various plasma inflammation-, angiogenesis-, and extracellular matrix remodeling-associated mediators for intra-amniotic inflammation and/or microbial invasion of the amniotic cavity in preterm labor.

PURPOSE: To determine whether various inflammatory-, angiogenic/anti-angiogenic-, and extracellular matrix remodeling-associated proteins in plasma, alone or in combination with conventional blood-based markers, can predict intra-amniotic inflammation and/or microbial invasion of the amniotic cavity (IAI/MIAC) in women with spontaneous preterm labor (PTL). METHODS: A total of 193 singleton pregnant women with PTL (23-33 weeks) were included in this retrospective cohort study. Plasma samples were obtained at the time of amniocentesis. Amniotic fluid (AF) was cultured for microorganism detection and consequent MIAC diagnosis. IL-6 levels were determined in AF and used to identify IAI (AF IL-6 ≥ 2.6 ng/mL). Endostatin, haptoglobin, IGFBP-2/3, LBP, M-CSF, MMP-2/8, pentraxin 3, PlGF, S100A8/A9, and VEGFR-1 levels were assayed in plasma samples by ELISA. CRP levels and neutrophil-to-lymphocyte ratio (NLR) were measured. RESULTS: Plasma LBP, MMP-8, and S100A8/A9 levels, CRP levels, and NLR were significantly higher, and plasma IGFBP-2 and MMP-2 levels were significantly lower in women with IAI/MIAC than in those without this condition, whereas no baseline variables differed significantly between the two groups. Using a stepwise regression analysis, a noninvasive prediction model for IAI/MIAC was developed, which included plasma LBP, MMP-2, and MMP-8 levels (area under the curve [AUC], 0.785). The AUC for this prediction model was significantly or borderline greater than that of any single factor included in the model. CONCLUSIONS: IGFBP-2, LBP, MMP-2, MMP-8, and S100A8/A9 may represent valuable plasma biomarkers for predicting IAI/MIAC in women with PTL. Combination of LBP, MMP-2, and MMP-8 expression data can significantly improve the predictive potential for IAI/MIAC.

Absolute counts of leukocyte subsets in peripheral blood in pregnancies complicated by preterm prelabour rupture of membranes.

BACKGROUND: This study aimed to assess variations in the absolute counts of various leukocyte subsets in the peripheral blood of women with pregnancies affected by preterm prelabour rupture of membranes (PPROM), in relation to the presence of intra-amniotic inflammation (IAI). METHODS: The study included fifty-two women with singleton pregnancies experiencing PPROM. Absolute counts of different leukocyte subpopulations, such as granulocytes, monocytes, lymphocytes, T cells and their subsets, B cells and their subsets, and NK cells and their subsets, were measured in maternal peripheral blood samples using multicolour flow cytometry. IAI was identified by elevated concentrations of interleukin 6 (IL-6) in the amniotic fluid, which was collected through transabdominal amniocentesis. RESULTS: Women with IAI exhibited higher absolute counts of leukocytes (p = 0.003), granulocytes (p = 0.008), and monocytes (p = 0.009). However, the presence of IAI did not significantly affect the absolute counts of lymphocytes or their subpopulations. CONCLUSIONS: The study found that IAI is associated with changes in the absolute counts of leukocytes from the innate immunity compartment in the peripheral blood of women with pregnancies complicated by PPROM. Conversely, it does not significantly alter the counts of cells from the adaptive immune system. The changes observed may reflect the natural, temporal, and localised characteristics of IAI.

Preterm birth is the most serious complication in contemporary perinatal medicine. Preterm birth, which is defined as a labour before the completion of 37 weeks of pregnancy, is often accompanied by premature rupture of the amniotic membranes and drainage of amniotic fluid. Such a situation is often complicated by inflammation, which adversely affects the health of the foetus. A number of procedures and markers have been developed for the diagnosis of inflammation, but they are determined from hard-to-reach amniotic fluid. It is therefore appropriate to try to find reliable markers of inflammation in the much more accessible maternal peripheral blood. Such a marker can be increased numbers of leukocytes, which have been repeatedly investigated in this context. However, little attention is directed to other leukocyte populations and especially to various lymphocyte subpopulations. This study aimed to test changes in absolute counts of different types of leukocytes and lymphocyte subpopulations in women with premature rupture of membranes with respect to ongoing inflammation. The results of the study showed that inflammation is accompanied by increased numbers of leukocytes, granulocytes and monocytes, however, the results did not show significant changes in the number of lymphocytes and their subpopulations.

Identification and characterization of plasma proteins associated with intra-amniotic inflammation and/or infection in women with preterm labor.

This study aimed to identify plasma proteins that could serve as potential biomarkers for microbial invasion of the amniotic cavity (MIAC) or intra-amniotic inflammation (IAI) in women with preterm labor (PTL). A retrospective cohort comprised singleton pregnant women with PTL (24-34 weeks) who underwent amniocentesis. Pooled plasma samples were analyzed by label-free liquid chromatography-tandem mass spectrometry for proteome profiling in a nested case-control study (concomitant MIAC/IAI cases vs. non-MIAC/IAI controls [n = 10 per group]). Eight target proteins associated with MIAC/IAI were further verified by immunoassays in a large cohort (n = 230). Shotgun proteomic analysis revealed 133 differentially expressed proteins (fold change > 1.5, P < 0.05) in the plasma of MIAC/IAI cases. Further quantification confirmed that the levels of AFP were higher and those of kallistatin and TGFBI were lower in the plasma of women with MIAC and that the levels of kallistatin and TGFBI were lower in the plasma of women with IAI than in those without these conditions. The area under the curves of plasma AFP, kallistatin, and TGFBI ranged within 0.67-0.81 with respect to each endpoint. In summary, plasma AFP, kallistatin, and TGFBI may represent valuable non-invasive biomarkers for predicting MIAC or IAI in women with PTL.

Plasma Kallistatin and Progranulin as Predictive Biomarkers of Intraamniotic Inflammation, Microbial Invasion of the Amniotic Cavity, and Composite Neonatal Morbidity/Mortality in Women With Preterm Premature Rupture of Membranes.

PROBLEM: To explore the clinical utility of nine inflammatory immune-, adhesion-, and extracellular matrix-related mediators in the plasma for predicting intraamniotic inflammation and/or microbial invasion of the amniotic cavity (IAI/MIAC) and composite neonatal morbidity and/or mortality (CNMM) in women with preterm premature rupture of membranes (PPROM) when used alone or in combination with conventional blood-, ultrasound-, and clinical-based factors. METHODS OF STUDY: This retrospective cohort comprised 173 singleton pregnant women with PPROM (24 + 0 - 33 + 6 weeks), who underwent amniocentesis. Amniotic fluid was cultured for microorganisms and assayed for IL-6 levels. Plasma levels of AFP, CXCL14, E-selectin, Gal-3BP, kallistatin, progranulin, P-selectin, TGFBI, and VDBP were determined by ELISA. Ultrasonographic cervical length (CL) and neutrophil-to-lymphocyte ratio (NLR) were measured. RESULTS: Multivariate logistic regression analyses revealed significant associations between (i) decreased plasma kallistatin levels and IAI/MIAC and (ii) decreased plasma progranulin levels and increased CNMM risk after adjusting for baseline variables (e.g., gestational age at sampling [or delivery] and parity). Using stepwise regression analysis, noninvasive prediction models for IAI/MIAC and CNMM risks were developed, which included plasma progranulin levels, NLR, CL, and gestational age at sampling, and provided a good prediction of the corresponding endpoints (area under the curve: 0.79 and 0.87, respectively). CONCLUSIONS: Kallistatin and progranulin are potentially valuable plasma biomarkers for predicting IAI/MIAC and CNMM in women with PPROM. Particularly, the combination of these plasma biomarkers with conventional blood-, ultrasound-, and clinical-based factors can significantly support the diagnosis of IAI/MIAC and CNMM.

Changes in serum inflammatory factors in group B streptococcal infection and their predictive value for premature rupture of membranes complicated by chorioamnionitis.

Objective: The aim of this study as to unveil changes in serum inflammatory factors in pregnant women with genital tract group B Streptococcus (GBS) infection and their predictive value for premature rupture of membranes (PROM) complicated by chorioamnionitis (CS) and adverse pregnancy outcomes. Methods: The value of serum inflammatory factor levels in predicting PROM complicating CS and adverse pregnancy outcomes in GBS-infected pregnant women was evaluated by ELISA. Results: Serum IL-6, TNF-α, PCT and hs-CRP levels were higher in pregnant women with GBS infection. The combined diagnosis of these factors had excellent diagnostic value in PROM complicating CS and adverse pregnancy outcomes. Conclusion: Joint prediction of IL-6, TNF-α, PCT and hs-CRP has the best predictive value for PROM complicating CS and adverse pregnancy outcomes.

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