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

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.

Contribution of vaginal culture to predict early onset neonatal infection in preterm prelabor rupture of membranes

BACKGROUND

Preterm prelabor rupture of membranes (PPROM) is a major cause of morbidity and mortality for both the mother and the newborn. The vaginal germ profile in PPROM is poorly known, particularly regarding the risk of early-onset neonatal infection (EONI).

OBJECTIVE

To determine microbiological risk factors for EONI in case of PPROM before 34 weeks of gestation (WG).

STUDY DESIGN

A retrospective single-center cohort of patients with PPROM before 34 W G from 2008 to 2016. Vaginal swabs were obtained at admission and at delivery as per usual care and were analyzed by Gram stain and culture for vaginal dysbiosisi.e lactobacilli depletion and/or presence of potential pathogens.

RESULTS

Among 268 cases of PPROM, 39 neonates had EONI 14.55 %; (95 %CI 0.11 - 0.19) Overall, vaginal samples culture was positive in 16.67 % (95 %CI 11.95 %-22.32 %) at the time of rupture and 24.76 % (95 %CI 19.02 %-31.23 %) at delivery, with no significant differences between EONI and no-EONI groups (p = 0.797 and 0.486, respectively), including for Group B Streptococci (GBS) and Escherichia coli. EONI was significantly associated with dysbiosis at the time of rupture (23.94 % versus 10.35 % in the absence of dysbiosis, p = 0.009) and at delivery (19.70 % versus 3.90 % if no dysbiosis, p < 0.001). Clinical intra-uterine infection was present in 78.5 % (n = 31) of the EONI group versus 37.2 % (n = 85) in the non-EONI group (p < 0.001) and chorioamnionitis and/or funisitis were found in 97.3 % and 91.9 %, respectively in the EONI group, versus 56.11 % and 53.96 %, respectively, in the non-EONI group (p < 0.001).

CONCLUSION

Dysbiosis following rupture and at delivery, but not the presence of pathogens in the VS culture, was associated with the risk of EONI in case of PPROM.

Hyperechoic amniotic membranes in patients with preterm premature rupture of membranes (p-PROM) and pregnancy outcome

OBJECTIVES

The early identification of women with preterm premature rupture of membranes (p-PROM) who are at higher risk of imminent delivery remains challenging. The aim of our study was to evaluate if an increased echogenicity of the amniotic membranes may represent a sonographic marker of impending delivery in women with p-PROM.

METHODS

This was a prospective study including women with singleton pregnancies and diagnosis of p-PROM between 22 and 37 gestational weeks. A sonographic examination was performed within 24 h from the hospital admission and the appearance of the amniotic membranes close to the internal os was specifically evaluated. The membranes were defined as hyperechoic when their echogenicity was similar to that of the fetal bones or normoechoic in the other cases. The primary aim of the study was to compare the admission to spontaneous onset of labor interval and the pregnancy outcome between the cases of p-PROM with and without hyperechoic membranes.

RESULTS

Overall, 45 women fulfilled the inclusion criteria with similar characteristics at admission. In women with hyperechoic membranes, the admission to spontaneous onset of labor interval was significantly shorter (11.5 [5.3-25.0] vs. 3.0 [1.5-9.0] p=0.04) compared to women with normo-echoic membranes. At binomial logistic regression after adjustment for GA at hospital admission, the presence of hyperechoic membranes was found as the only independent predictor of spontaneous onset of labor ≤72 h (aOR: 6.1; 95% CI: 1.0-36.9).

CONCLUSIONS

The presence of hyperechoic membranes is associated with a 6-fold higher incidence of spontaneous onset of labor within 72 h independently from the gestational age at p-PROM.

Prognostic Markers for Chorioamnionitis: IL-6, TNF-α, and MMP-8 in Vaginally Obtained Amniotic Fluid

Background. Earlier chorioamnionitis diagnosis is crucial to improve maternal and neonatal health outcomes. This study was conducted to evaluate the inlerleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and matrix metalloproteinase 8 (MMP-8) levels in vaginally obtained amniotic fluid to investigate their prognostic value and to determine the most appropriate cut-off values for the prediction of chorioamnionitis. Methods. This case control study included women who were diagnosed with preterm premature rupture of the membranes before 34 weeks of gestation and were admitted to Vilnius University Hospital Santaros Klinikos. Free-leaking amniotic fluid was obtained vaginally with a sterile speculum less than 48h before delivery. Amniotic fluid IL-6, TNF-α, and MMP-8 levels were determined by the Enzyme Linked Immunosorbent Assay. Diagnosis of chorioamnionitis was confirmed by histological examination of the placenta and membranes after delivery. Results. The study included 156 women, 65 patients in the histological chorioamnionitis group (Group I) and 91 in a group without diagnosed histological chorioamnionitis (Group II). The median concentrations of IL-6, MMP-8, and TNF-α in amniotic fluid were statistically significantly higher in Group I than in Group II (p-value < 0.001). The area under the curve of TNF-α and MMP-8 were higher than the area under the curve of IL-6 (0.91, 0.89, and 0.81, respectively). No statistically significant difference was found when comparing the receiver operating characteristic (ROC) curves of TNF-α and MMP-8. The optimum cut-off values for the prediction of chorioamnionitis were found to be 1389.82 pg/mL for IL-6, 21.17 pg/mL for TNF-α, and 172.53 ng/mL for MMP-8. The sensitivity, specificity, positive prognostic value (PPV), and negative prognostic value (NPV) of the IL-6 cut-off for chorioamnionitis were 88%, 70%, 67%, and 89%, respectively. The sensitivity, specificity, PPV, and NPV of the TNF-α cut-off were 88%, 84%, 79%, and 90%, respectively. The sensitivity, specificity, PPV, and NPV of the MMP-8 cut-off were 80%, 87%, 81%, and 86%, respectively. Conclusions. The vaginally obtained amniotic fluid IL-6, MMP-8, and TNF-α seem to be good predictors for chorioamnionitis of patients with preterm premature rupture of membranes before 34 weeks of gestation. The noninvasive technique of sampling amniotic fluid could be alternative method to invasive amniocentesis.

Maternal inflammatory markers for chorioamnionitis in preterm prelabour rupture of membranes: a systematic review and meta-analysis of diagnostic test accuracy studies

BACKGROUND

There is no consensus on the role of inflammatory markers in identifying chorioamnionitis in preterm prelabour rupture of membranes (PPROM). We set out to evaluate the accuracy of maternal blood C-reactive protein (CRP), procalcitonin and interleukin 6 (IL6) in diagnosis of histological chorioamnionitis and/or funisitis (HCA/Funisitis) in PPROM.

METHODS

We searched MEDLINE, EMBASE and The Cochrane Library from inception to January 2020 for studies where maternal blood CRP, procalcitonin or IL6 was assessed against a reference standard of HCA/Funisitis in PPROM. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool was used to assess methodological quality. Hierarchical summary receiver operating characteristic (SROC) models were used to construct summary curves. Bivariate models were used to obtain summary estimates for studies with the same cut-off.

RESULTS

We included 23 studies reporting HCA/Funisitis in 902 of 1717 women, median prevalence 50% (inter-quartile range 38-57). Of these studies, 20 were prospective cohort design and 3 were retrospective cohort. Eleven studies reported the index test against a reference standard of HCA and/or funisitis, 10 reported HCA alone and 2 reported funisitis alone. Many studies had high risk of bias scores on the QUADAS-2 assessment but low concerns for applicability. Sensitivity and specificity for CRP ≥ 20 mg/L (5 studies, 252 participants) was 59% (95% CI 48-69) and 83% (95% CI 74-89) respectively. SROC curves are provided for each index test. At selected specificity of 80%, the sensitivities for CRP (all cut-offs, 17 studies, 1404 participants), PCT ( all cut-offs, 6 studies, 231 participants) and IL6 (all cut-offs, 5 studies, 299 participants) were 59%(95% CI 52-68), 56%(95% CI 50-69) and 52% (95% CI 50-86) respectively.

CONCLUSIONS

There is insufficient evidence to support use of CRP, procalcitonin or IL6 in maternal blood for diagnosis of HCA/Funisitis in PPROM. This review followed recommended methodology and data analytic methods that made the most of the data regardless of the different cut-offs used. However, the evidence is based on few studies with generally small sample sizes, poor-quality scores and substantial heterogeneity. There is a need for good-quality diagnostic accuracy studies to better assess the role of these biomarkers in PPROM.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration number: CRD42015023899, registered on 8 October 2015.

Value of cervicovaginal fluid cytokines in prediction of fetal inflammatory response syndrome in pregnancies complicated with preterm premature rupture of membranes (pPROM)

Background Preterm premature rupture of membranes (pPROM) is associated with a high risk of prematurity and complications of fetal inflammatory response syndrome (FIRS). The aim of the study is to determine any correlations between the concentration of selected cytokines contained in the cervicovaginal secretion eluates and in the umbilical cord plasma in patients with pPROM and to find the noninvasive markers of FIRS in order to pinpoint the optimal time of the delivery. Methods The study included 80 patients with pPROM between the 24th and 34th week of gestation. The cervicovaginal fluid and umbilical cord blood were collected. Interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 19 (IL-19) and tumor necrosis factor-α (TNF-α) concentrations were measured in both materials. For the statistical analysis, SigmaStat3.5 software was used. Results There was no direct association in levels of IL-6, TNF-α, IL-10 and IL-19 between the cord blood and cervicovaginal secretions within the studied group. The cut-off point of IL-6 of 26.8 pg/mL in the vaginal fluid had high sensitivity and specificity in order to discriminate between newborns with and without FIRS (81.08%; 76.74%). Conclusion Further studies are needed on a larger group of participants to demonstrate that an elevated concentration of IL-6 above 26.8 pg/mL in the cervicovaginal secretion eluate is an indirect noninvasive marker of FIRS.

Diagnostic value of Chorioquick for detecting chorioamnionitis in women with premature rupture of membranes

OBJECTIVE

To determine the accuracy of a semi-quantitative interleukin-6 (IL-6) vaginal secretion rapid test (Chorioquick) for detecting chorioamnionitis in women with premature rupture of membranes (PROM).

METHODS

A prospective cohort study in five tertiary hospitals in Nigeria involved women with confirmed PROM at term and preterm PROM with or without suspected chorioamnionitis from August 1, 2017, to October 31, 2018. Cervicovaginal fluid samples were tested for chorioamnionitis using the Chorioquick test. Samples were repeated at decision to deliver. The test was considered positive if at least the indicator 'IL-6 low' of the three Chorioquick biomarkers (low, medium, high) was positive, or negative if none of the biomarkers were positive. Chorioamnionitis was histologically confirmed post-delivery using three tissue samples. Primary outcome measures were sensitivity, specificity, and accuracy.

RESULTS

Of 73 women, on histological confirmation, 39 were true positive and 29 were true negative (for chorioamnionitis) to the Chorioquick test at repeat assessment. Overall, the Chorioquick test had a sensitivity of 97.5% (95% confidence interval [CI] 85.3-99.9), specificity 87.9% (70.9-96.0), and accuracy 93.2% (79.5-99.1). Sub-group analysis of women <37 weeks of pregnancy showed a sensitivity of 100.0% (95% CI 83.4-100.0), specificity of 91.3% (70.5-98.5), and accuracy of 95.8% (82.5-99.5). Triple positive samples were 100.0% specific in all gestations.

CONCLUSION

Chorioquick showed favorable utility for detecting chorioamnionitis in PROM and could be a reliable, non-invasive rapid tool in a real-world clinical setting.

Interleukin-6 for early diagnosis of neonatal sepsis with premature rupture of the membranes: A meta-analysis

BACKGROUND

Premature rupture of the membranes (PROM) is the principal risk factor for neonatal sepsis. Interleukin-6 (IL-6) has been investigated for early diagnosis of neonatal sepsis, but not for diagnosis of neonatal sepsis with PROM. The objective of this study is to investigate the early diagnostic value of IL-6 for neonatal sepsis with PROM.

METHODS

The literature was searched using PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wan Fang, VIP, and CBM databases until March 2018. Each study was evaluated using Quality Assessment of Diagnostic Accuracy Studies tool-2. We used a bivariate diagnostic random-effects model.

RESULTS

The overall pooled sensitivity, specificity, positive likelihood rate, negative likelihood rate, diagnostic odds ratio, and area under the summary receiver operating characteristic curve were 0.85 (95% confidence interval [CI]: 0.81-0.91), 0.88 (95% CI: 0.86-0.91), 9.94 (95% CI: 4.27-23.15), 0.14 (95% CI: 0.06-0.32), 79.26 (95% CI: 23.42-268.26), and 0.9473, respectively, which showed high accuracy in diagnosing neonatal sepsis with PROM. The types of sepsis might be connected with the source of heterogeneity (P = .0351).

CONCLUSION

IL-6 is therefore a sensitive and specific diagnostic marker for the early diagnosis of neonatal sepsis with PROM.

[Modalities of birth in case of uncomplicated preterm premature rupture of membranes: CNGOF Preterm Premature Rupture of Membranes Guidelines]

OBJECTIVE

To identify the ideal gestational age at delivery for preterm premature rupture of membranes and modalities of birth.

METHOD

To identify studies, research was conducted using Pub-Med, Embase and Cochrane databases.

RESULTS

Prolonged latency duration after pPROM does not worsen neonatal prognosis (NP3). Therefore, it is recommended not to deliver before 34 weeks of gestation for patient with uncomplicated preterm rupture of membranes (pPROM) (Grade C). After 34 weeks of gestation, expectant management for pPROM is not associated with neonatal sepsis (NP1) but is associated to intra-uterine infection (NP2). Early delivery is associated with higher risk of respiratory distress syndrome (NP2), higher risk of cesarean section (NP2) and longer duration of NICU hospitalization (NP2). Before 37 weeks of gestation, expectant management is recommended for uncomplicated pPROM (Grade A), even if vaginal group B streptococcus is positive, as long as antibiotics are used at the time of membranes rupture (Professional consensus). Elective cesarean section is reserved for usual obstetrical indications. Oxytocin and prostaglandins are reasonable options for inducing labor (Professional consensus). Data are too scarce to establish recommendation regarding intra-cervical balloons in case of pPROM (Professional consensus).

CONCLUSION

Expectant management is recommended for uncomplicated pPROM before 37 weeks of gestation.

[Management of preterm premature rupture of membranes (except for antibiotherapy): CNGOF preterm premature rupture of membranes guidelines]

OBJECTIVE

To review the different parts of therapeutic management of viable preterm premature rupture of membranes (PPROM), except the antibiotherapy and birth modalities.

METHODS

The Medline, Cochrane Library, and Google Scholar databases over a period from 1980 to September 2018 have been consulted.

RESULTS

When the diagnostic of viable PPROM is reached, the woman should be hospitalized and signs of intrauterine infection (IUI) should be sought (Professional consensus). If cervical assessment appears necessary, speculum, digital examination or cervical ultrasound may be performed (Professional consensus). It is recommended to limit cervical evaluation regardless of the method used (Professional consensus). Initial ultrasound is recommended to determine the fetal presentation, locate the placenta, estimate the fetal weight and the residual amniotic fluid volume (Professional consensus). Performing vaginal and urinary bacteriological sampling at admission is recommended before any antibiotic (Professional consensus). In the case of positive vaginal culture, an antibiogram is necessary since it can guide antibiotherapy in the case of IUI and early onset neonatal bacterial sepsis (Professional consensus). In absence of demonstrated neonatal benefit, there is insufficient evidence to recommend or to not recommend initial tocolysis in PPROM (Grade C). If tocolysis was administered, it is recommended not to prolong it for more than 48hours (Grade C). Antenatal corticosteroid administration is recommended before 34 weeks of gestation (WG) (Grade A) and magnesium sulfate administration is recommended for women at high risk of imminent preterm birth before 32 WG (Grade A). Vitamin supplementation (vitamins C and E) is not recommended (Professional consensus), and it is recommended not to impose strict bed rest in case of PPROM (Professional consensus). In case of clinical signs of IUI with cerclage, it is recommended to remove the cerclage immediately (Professional consensus). The home care management of clinically stable PPROM after 48hours of hospital observation can be considered (Professional consensus). During the monitoring of a PPROM, it is recommended to identify elements relating to the diagnosis of IUI (Professional consensus).

CONCLUSION

The level of evidence and scientific data in the literature concerning the management (except antibiotics) of PPROM are low. Initial management of viable PPROM requires hospitalization. The main objectives of the management are the detection and medical care of maternal and fetal complications.

[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).