Vaginal Fluid Inflammatory Biomarkers and the Risk of Adverse Neonatal Outcomes in Women with PPROM

Investigating the Association between Serum and Hematological Biomarkers and Neonatal Sepsis in Newborns with Premature Rupture of Membranes: A Retrospective Study

(1) Background: Neonatal early-onset sepsis (EOS) is associated with important mortality and morbidity. The aims of this study were to evaluate the association between serum and hematological biomarkers with early onset neonatal sepsis in a cohort of patients with prolonged rupture of membranes (PROM) and to calculate their diagnostic accuracy. (2) Methods: A retrospective cohort study was conducted on 1355 newborns with PROM admitted between January 2017 and March 2020, who were divided into two groups: group A, with PROM ≥ 18 h, and group B, with ROM < 18 h. Both groups were further split into subgroups: proven sepsis, presumed sepsis, and no sepsis. Descriptive statistics, analysis of variance (ANOVA) and a Random Effects Generalized Least Squares (GLS) regression were used to evaluate the data. (3) Results: The statistically significant predictors of neonatal sepsis were the high white blood cell count from the first (p = 0.005) and third day (p = 0.028), and high C-reactive protein (CRP) values from the first day (p = 0.004). Procalcitonin (area under the curve-AUC = 0.78) and CRP (AUC = 0.76) measured on the first day had the best predictive performance for early-onset neonatal sepsis. (4) Conclusions: Our results outline the feasibility of using procalcitonin and CRP measured on the first day taken individually in order to increase the detection rate of early-onset neonatal sepsis, in the absence of positive blood culture.

The significance of TNF-α and MMP-8 concentrations in non-invasively obtained amniotic fluid predicting fetal inflammatory response syndrome

OBJECTIVE

To determine the significance of tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-8 (MMP-8) in vaginally obtained amniotic fluid predicting fetal inflammatory response syndrome (FIRS) after preterm premature rupture of membranes (PPROM).

METHODS

In this prospective case-control study, TNF-α and MMP-8 concentrations were evaluated in vaginally obtained amniotic fluid from women with PPROM at 22-34 weeks of pregnancy. Biomarkers' concentrations were determined using an enzyme-linked immunosorbent assay. Patients were divided into two groups: the FIRS group (cord blood interleukin-6 > 11 pg/ml or histological funisitis) and the non-FIRS group (without these findings). The data were analyzed using R package (R-4.0.5).

RESULTS

The median TNF-α and MMP-8 concentrations in amniotic fluid from the 145 women included in the study were higher in the FIRS group than in the non-FIRS group. The area under the curve of TNF-α and MMP-8 was 0.77 and 0.75, respectively. The TNF-α concentration cut-off predicting FIRS was 89.20 pg/ml and was 170.76 pg/ml for MMP-8. In regression analysis, MMP-8 concentration was an independent predictor for FIRS. An MMP-8 concentration greater than 170 ng/ml and a TNF-α concentration greater than 89 pg/ml increased the odds of FIRS 7.62 and 14.92 times, respectively.

CONCLUSIONS

MMP-8 and TNF-α concentrations in vaginally obtained amniotic fluid may be good predictors for FIRS after PPROM before 34 weeks of pregnancy. The non-invasive amniotic fluid analysis could be an alternative method to invasive amniocentesis.

Pathophysiological Implication of Pattern Recognition Receptors in Fetal Membranes Rupture: RAGE and NLRP Inflammasome

Preterm prelabor ruptures of fetal membranes (pPROM) are a pregnancy complication responsible for 30% of all preterm births. This pathology currently appears more as a consequence of early and uncontrolled process runaway activation, which is usually implicated in the physiologic rupture at term: inflammation. This phenomenon can be septic but also sterile. In this latter case, the inflammation depends on some specific molecules called “alarmins” or “damage-associated molecular patterns” (DAMPs) that are recognized by pattern recognition receptors (PRRs), leading to a microbial-free inflammatory response. Recent data clarify how this activation works and which receptor translates this inflammatory signaling into fetal membranes (FM) to manage a successful rupture after 37 weeks of gestation. In this context, this review focused on two PRRs: the receptor for advanced glycation end-products (RAGE) and the NLRP7 inflammasome.

Biostatistics Health Assessment of Matrix Metalloproteinases in Vaginal Secretions in Late Pregnant Women

Objective: The health management of pregnant women in late pregnancy is difficult. Once vaginal infection occurs, adverse pregnancy outcomes will occur. The aim of this study was to explore the application value of biostatistics health assessment of matrix metalloproteinases (MMP) in vaginal secretions in late pregnant women with vaginal infection. Methods: A total of 120 late pregnant women with vaginal infection, including vulvovaginal candidiasis (WC) in 70 cases and bacterial vaginosis (BV) in 50 cases, were selected as the experimental group. Another 80 pregnant women with normal vaginal secretion in the same gestational week were randomly selected as the control group. Vaginal soft capsule of mycomycin was used in the treatment. The expression levels of MMP-8 and MMP-9 in vaginal secretions before and after treatment were detected by enzyme-linked immunosorbent assay (ELISA) and smear immunohistochemistry, Results: Both the ELISA and immunohistochemistry analysis showed that the levels of MMP-8 and MMP-9 in the vaginal secretion of experimental group were significantly increased than the data of control group (P < 0.05). After effective intervention, the levels of MMP-8 and MMP-9 were significantly lower than those before treatment (P < 0.05). Conclusion: The late pregnant women with vaginal infection was accompanied by the high level of MMP-8 and MMP-9 in vaginal secretions. Effective intervention will lead the reduction of MMP. Thus, the biostatistics health assessment of MMP is important for the late pregnant women with vaginal infection.

Daily monitoring of vaginal interleukin 6 as a predictor of intraamniotic inflammation after preterm premature rupture of membranes - a new method of sampling studied in a prospective multicenter trial

OBJECTIVES

(A) To introduce a new technique for vaginal fluid sampling (biocompatible synthetic fiber sponge) and (B) evaluate the collected vaginal fluid interleukine-6 (IL-6_vag)-concentration as a new diagnostic tool for daily monitoring of intrauterine inflammation after preterm premature rupture of membranes (PPROM). Secondary objectives were to compare the potential to predict an intrauterine inflammation with established inflammation parameters (e.g., maternal white blood cell count).

METHODS

This prospective clinical case-control diagnostic accuracy multicenter study was performed with women after PPROM (gestational age 24.0/7 - 34.0/7 weeks). Sampling of vaginal fluid was performed once daily. IL-6_vag was determined by electrochemiluminescence-immunoassay-kit. Neonatal outcome and placental histology results were used to retrospectively allocate the cohort into two subgroups: 1) inflammation and 2) no inflammation (controls).

RESULTS

A total of 37 cases were included in the final analysis. (A): Measurement of IL-6 was successful in 86% of 172 vaginal fluid samples. (B): Median concentration of IL-6_vag in the last vaginal fluid sample before delivery was significantly higher within the inflammation group (17,085 pg/mL) compared to the controls (1,888 pg/mL; p=0.01). By Youden's index an optimal cut-off for prediction an intrauterine inflammation was: 6,417 pg/mL. Two days before delivery, in contrast to all other parameters IL-6_vag remained the only parameter with a sufficient AUC of 0.877, p<0.001, 95%CI [0.670-1.000].

CONCLUSIONS

This study established a new technique for vaginal fluid sampling, which permits assessment of IL-6_vag concentration noninvasively in clinical daily routine monitoring.

The Potential of Metabolomic Analyses as Predictive Biomarkers of Preterm Delivery: A Systematic Review

SCOPE

as the leading cause of perinatal mortality and morbidity worldwide, the impact of premature delivery is undisputable. Thus far, non-invasive, cost-efficient and accurate biochemical markers to predict preterm delivery are scarce. The aim of this systematic review is to investigate the potential of non-invasive metabolomic biomarkers for the prediction of preterm delivery.

METHODS AND RESULTS

Databases were systematically searched from March 2019 up to May 2020 resulting in 4062 articles, of which 45 were retrieved for full-text assessment. The resulting metabolites used for further analyses, such as ferritin, prostaglandin and different vitamins were obtained from different human anatomical compartments or sources (vaginal fluid, serum, urine and umbilical cord) and compared between groups of women with preterm and term delivery. None of the reported metabolites showed uniform results, however, a combination of metabolomics biomarkers may have potential to predict preterm delivery and need to be evaluated in future studies.

[Diagnosis and management of intra-uterine infection: CNGOF Preterm Premature Rupture of Membranes Guidelines]

OBJECTIVE

To determine the diagnosis criteria and management of intra-uterine inflammation or infection (Triple I, III).

METHODS

PubMed and Cochrane Central databases search.

RESULTS

III is defined as an infection of the fetal membranes, and/or other components like the decidua, fetus, amniotic fluid or placenta. This word should be preferred to the word chorioamnionitis that is less precise (Professional consensus). III clinical signs exhibit poor limited sensibility and specificity (EL3). The diagnosis of III is retained in case of maternal fever (defined by a body temperature≥38°C) with no alternative cause identified and at least 2 signs among the following: fetal tachycardia>160 bpm for 10min or longer, uterine pain of labor, purulent fluid from the cervical canal (Professional consensus). Maternal hyperleukocytosis>20 giga/L in the absence of corticosteroids treatment or increased plasmatic C-reactive protein also argue for III, despite their limited sensibility and specificity (EL3). III requires prompt delivery (Grade A). III is not by itself an indication for cesarean delivery (Professional consensus). Antibiotic treatment should cover Streptococcus agalactiae and Escherichia coli. Antibiotics should be started immediately and maintained all over delivery, to reduce neonatal and maternal morbidity (Grade B). Treatment should rely on a combination of betalactamin and aminoglycoside (Grade B). After vaginal delivery, one single dose of antibiotic is required. Antibiotic duration should be longer in case of bacteremia. Longer duration could be considered in case of persistent fever or of cesarean delivery (Professional consensus).

Mid-trimester preterm premature rupture of membranes (PPROM): etiology, diagnosis, classification, international recommendations of treatment options and outcome

Mid-trimester preterm premature rupture of membranes (PPROM), defined as rupture of fetal membranes prior to 28 weeks of gestation, complicates approximately 0.4%-0.7% of all pregnancies. This condition is associated with a very high neonatal mortality rate as well as an increased risk of long- and short-term severe neonatal morbidity. The causes of the mid-trimester PPROM are multifactorial. Altered membrane morphology including marked swelling and disruption of the collagen network which is seen with PPROM can be triggered by bacterial products or/and pro-inflammatory cytokines. Activation of matrix metalloproteinases (MMP) have been implicated in the mechanism of PPROM. The propagation of bacteria is an important contributing factor not only in PPROM, but also in adverse neonatal and maternal outcomes after PPROM. Inflammatory mediators likely play a causative role in both disruption of fetal membrane integrity and activation of uterine contraction. The "classic PPROM" with oligo/an-hydramnion is associated with a short latency period and worse neonatal outcome compared to similar gestational aged neonates delivered without antecedent PPROM. The "high PPROM" syndrome is defined as a defect of the chorio-amniotic membranes, which is not located over the internal cervical os. It may be associated with either a normal or reduced amount of amniotic fluid. It may explain why sensitive biochemical tests such as the Amniosure (PAMG-1) or IGFBP-1/alpha fetoprotein test can have a positive result without other signs of overt ROM such as fluid leakage with Valsalva. The membrane defect following fetoscopy also fulfils the criteria for "high PPROM" syndrome. In some cases, the rupture of only one membrane - either the chorionic or amniotic membrane, resulting in "pre-PPROM" could precede "classic PPROM" or "high PPROM". The diagnosis of PPROM is classically established by identification of nitrazine positive, fern positive watery leakage from the cervical canal observed during in specula investigation. Other more recent diagnostic tests include the vaginal swab assay for placental alpha macroglobulin-1 test or AFP and IGFBP1. In some rare cases amniocentesis and infusion of indigo carmine has been used to confirm the diagnosis of PPROM. The management of the PPROM requires balancing the potential neonatal benefits from prolongation of the pregnancy with the risk of intra-amniotic infection and its consequences for the mother and infant. Close monitoring for signs of chorioamnionitis (e.g. body temperature, CTG, CRP, leucocytes, IL-6, procalcitonine, amniotic fluid examinations) is necessary to minimize the risk of neonatal and maternal complications. In addition to delayed delivery, broad spectrum antibiotics of penicillin or cephalosporin group and/or macrolide and corticosteroids have been show to improve neonatal outcome [reducing risk of chorioamnionitis (average risk ratio (RR)=0.66), neonatal infections (RR=0.67) and abnormal ultrasound scan of neonatal brain (RR=0.67)]. The positive effect of continuous amnioinfusion through the subcutaneously implanted perinatal port system with amniotic fluid like hypo-osmotic solution in "classic PPROM" less than 28/0 weeks' gestation shows promise but must be proved in future prospective randomized studies. Systemic antibiotics administration in "pre-PPROM" without infection and hospitalization are also of questionable benefit and needs to be further evaluated in well-designed randomized prospective studies to evaluate if it is associated with any neonatal benefit as well as the relationship to possible adverse effect of antibiotics on to fetal development and neurological outcome.

Predictive value of vaginal IL-6 and TNFα bedside tests repeated until delivery for the prediction of maternal-fetal infection in cases of premature rupture of membranes

OBJECTIVE

Examine the predictive value for maternal-fetal infection of routine bedside tests detecting the proinflammatory cytokines, TNFα and IL-6, in the vaginal secretions of women with premature rupture of the membranes (PROM).

STUDY DESIGN

This prospective two-center cohort study included all women hospitalized for PROM over a 2-year period. A bedside test assessed IL-6 and TNFα in vaginal secretions. Both centers routinely tested CRP and leukocytes, assaying both in maternal serum, and analyzed vaginal bacterial flora; all samples were repeated twice weekly until delivery.

RESULTS

The study included 689 women. In cases of preterm PROM (PPROM) before 37 weeks (n=184), a vaginal sample positive for one or more bacteria was the only marker associated with early neonatal infection (OR 5.6, 95%CI; 2.0-15.7). Its sensitivity was 82% (95%CI; 62-94) and its specificity 56% (95%CI; 47-65). All positive markers of infection were associated with the occurrence of chorioamnionitis. In cases of PROM from 37 weeks onward (n=505), only CRP >5mg/dL was associated with early neonatal infection (OR=8.3, 95%CI; 1.1-65.4) or clinical chorioamnionitis (OR=6.8, 95%CI; 1.5-30.0). The sensitivity of CRP >5mg/dL was 91% (95%CI; 59-100) and its specificity 45% (95%CI; 40-51) for predicting early neonatal infection, and 89% (95%CI; 65-99) and 46% (95%CI; 41-51), respectively, for predicting clinical chorioamnionitis.

CONCLUSION

The association of vaginal cytokines with maternal-fetal infection is weak and thus prevents their use as a good predictor of maternal-fetal infection. CRP and vaginal samples may be useful for identifying a group of women at low risk of infection.