Cervical bacterial colonization in women with preterm premature rupture of membrane and pregnancy outcomes: A cohort study

Significance of cervical secretion culture in predicting maternal and fetal outcome in pregnant women with premature rupture of membranes: a retrospective cohort study

Background: To investigate the clinical value of cervical secretion culture in pregnant women with premature rupture of membranes (PROM) in predicting maternal and fetal outcomes. Methods: We retrospectively reviewed clinical records of pregnant women who underwent obstetric examination and delivered in Fujian Maternal and Child Healthcare from December 2013 to December 2016. Pregnant women with a clear diagnosis of PROM, who underwent cervical secretion culture immediately after hospital admission were selected for the study. The primary outcome was the occurrence of chorioamnionitis. The secondary outcome was neonatal admission to the neonatal intensive care unit (NICU). Correlation between maternal and fetal outcomes and the results of the cervical secretion culture was analyzed by one-way analysis and multifactorial analysis, respectively. The predictive efficacy of cervical secretion culture was evaluated using receiver operating characteristic curve (ROC), area under the curve (AUC) and the integrated discrimination improvement (IDI). Results: A total of 7,727 pregnant women with PROM were included in the study. Of them, 1812 had positive cervical secretion cultures (635 positive for mycoplasma infection, 475 for bacterial, 637 for fungal, and 65 for chlamydial infections). Pregnant women with positive mycoplasma and bacterial cultures had higher rates of developing chorioamnionitis compared to women with negative cervical secretion cultures (9%, 12% vs. 1%, respectively). Similarly, positive mycoplasma and bacterial cultures were associated with higher rate of the preterm (before 34 weeks) labor (3%, 3% vs. 1% in women with negative cultures, respectively), and neonatal admission to the NICU (9%, 11% vs. 7%, respectively). After adjusting for various confounding factors, our analysis demonstrated that a positive cervical secretion culture for mycoplasma or bacterial pathogens remained an independent risk factor for chorioamnionitis. Cervical secretion culture outcome was less effective in predicting chorioamnionitis (AUC 0.569) compared to white blood count (WBC) (AUC 0.626) and C-reactive protein (CRP) levels (AUC 0.605). The IDI of the combined predictive model incorporating WBC, CRP, maternal fever and cervical secretion culture results was 0.0029. Conclusion: Positive cervical secretion cultures, especially for mycoplasma and bacteria, are associated with higher incidence of adverse maternal and fetal outcomes. However, the predictive value of this test is poor, and cannot be efficiently used for predicting chorioamnionitis.

Antibiotic prophylaxis in pregnant with premature rupture of ovular membranes: systematic review and meta-analysis

OBJECTIVE

To perform a systematic review and meta-analysis of randomized clinical trials that compared the use of antibiotics versus placebo in premature rupture of membranes preterm and evaluated maternal, fetal and neonatal outcomes in pregnant women with premature rupture of ovular membranes at a gestational age between 24 and 37 weeks.

METHODS

A search was conducted using keywords in PubMed, Cochrane, Biblioteca Virtual em Saúde and Biblioteca Digital de Teses e Dissertações da USP between August 2018 and December 2021. A total of 926 articles were found. Those included were randomized clinical trials that compared the use of antibiotics versus placebo in the premature rupture of preterm membranes. Articles referring to antibiotics only for streptococcus agalactiae prophylaxis were excluded. The retrieved articles were independently and blindly analyzed by two reviewers. A total of 24 manuscripts met the inclusion criteria and 21 articles were included for quantitative analysis.

RESULTS

Among the maternal outcomes analyzed, there was a prolongation of the latency period that was ≥7 days. In addition, we observed a reduction in chorioamnionitis in the group of pregnant women who used antibiotics. As for endometritis and other maternal outcomes, there was no statistically significant difference between the groups. Regarding fetal outcomes, antibiotic prophylaxis worked as a protective factor for neonatal sepsis. Necrotizing enterocolitis and respiratory distress syndrome showed no statistically significant differences.

CONCLUSION

The study showed positive results in relation to antibiotic prophylaxis to prolong the latency period, new randomized clinical trials are needed to ensure its beneficial effect.

PROSPERO DATABASE REGISTRATION

(www.crd.york.ac.uk/prospero) under number CRD42020155315.

Clinical and biochemical markers of spontaneous preterm birth in singleton and multiple pregnancies

AIM

The aim of this study was to compare the clinical characteristics of singleton and twin pregnancies that resulted in spontaneous preterm births (sPTB) and to evaluate the prognostic value of phosphorylated insulin-like growth factor binding protein-1 (phIGFB-1) and placental alpha macroglobulin-1(PAMG-1) for sPTB prediction in symptomatic women.

PATIENTS AND METHODS

The study included 420 women and included two parts. Firstly, we performed a retrospective cohort study comparing pregnancy and neonatal outcomes in 170 women with singleton pregnancies and spontaneous preterm birth before 37 weeks of gestation with 150 women with twin pregnancies who delivered at the same gestational age. In order to obtain the link between clinical and biochemical predictors of preterm labor we organized the second part of the research. The second part was a prospective observational study in 100 women with singleton and twin pregnancies between 24 and 33 + 6 weeks of gestation and symptoms of threatening preterm labor and intact membranes. We assessed the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for phIGFBP-1 and PAMG-1 in terms of sPTB within 7 days and 14 days after testing.

RESULTS

The rate of preterm premature rupture of membranes was higher in singleton pregnancies (67.1 versus 42.8%, p = 0.034). Cervical shortening in multiples was diagnosed at an earlier mean gestational age than in singleton pregnancies (30.1 ± 4.3 versus 35.9 ± 3.1 weeks, p = 0.013). In the singleton pregnancies group, the rate of microbial cervical colonization and the rate of bacterial vaginosis were significantly higher than in twin pregnancies (49.4 versus 15.3%, p < 0.001; 32.9 versus 12.0%, p = 0.007, respectively). Premature twins had a longer oxygen dependency period, while the singletons were more predisposed to infectious morbidity. The study showed low sensitivity of phIGFBP-1 for sPTB, while the sensitivity of the PAMG-1 test was higher (sensitivity 60% and 90% within 7 days after testing and 50 versus 75% within 14 days after testing). Both tests showed a high NPV for sPTB (93.3% for phIGFBP-1 versus 98.9% for PAMG-1). The NPV for preterm labor in twins was also high for both tests (93% for phIGFBP-1 and 96% for PAMG-1).

CONCLUSION

Cervical shortening is the main risk factor of sPTB in women with twin pregnancies; sPTB among singletons is associated with ascendent infection, involving fetal membranes. The PAMG-1 test showed high PPV and NPV for sPTB in symptomatic women and could be a reliable prognostic tool in clinical obstetrics. High NPV was observed for phIGFBP-1 and PAMG-1 in twin pregnancies.

Distribution of Streptococcus agalactiae Among Iranian Women from 1992 to 2018: A Systematic Review and Meta-Analysis

Context: Group B Streptococcus has the capacity of being colonized in the rectovaginal organ of women and causes infections in a mother and her fetus, thereby leading to neonatal diseases. Evidence Acquisition: The aim of this review was to summarize all of the relevant articles published to highlight the prevalence of group B Streptococcus colonization or infection in different regions of Iran. A systematic literature review was conducted by searching PubMed, Scopus, Web of Science (ISI), ScienceDirect, Google Scholar, and domestic databases for papers published in English or Persian from 1992 up to July 2019, concerning the prevalence of group B Streptococcus among Iranian women. All information regarding year, location of cases, frequency, author’s name, date of publication, participants, pregnancy period, sampling, and quality assessment were recorded. Summary effects were derived using the random effects model. Results: Among 61 suitable papers, data revealed that 36,807 cases of pregnant and non-pregnant women had been tested for group B Streptococcus during 1992-2018. Overall, 11.9% of pregnant and 5.3% of non-pregnant women were positive. Further results were as follows: vaginal, recto-vaginal, rectal, and endocervical colonization rates were 12.9%, 9.7%, 18.5%, and 3.7%, respectively. Group B Streptococcus incidence was the highest in Sanandaj (61.5%), and the lowest in Tabriz (1.8%). Conclusions: Although the prevalence distribution in Iran seems to be acceptable, more investigations are needed to represent the real incidence of group B Streptococcus around the country. In addition, a program with a standard lab technique is needed to screen pregnant women for further treatment before birth.

A role for the NLRC4 inflammasome in premature rupture of membrane

PROM is one of the common complications of perinatal period, which seriously threatens the mother and newborn. The purpose of this study was to identify the role of NLRC4 inflammasomes in this process and their underlying mechanisms. We performed high-throughput RNA sequencing of fetal membrane tissue from 3 normal pregnant women and 3 term-premature rupture of fetal membrane (TPROM) patients who met the inclusion criteria, and found that NLRC4 was significantly up-regulated in TPROM patients. An observational study of TPROM patients (PROM group, n = 30) and normal pregnant women (control group, n = 30) was performed at the Xuzhou Maternal and Child Health Hospital affiliated to Xuzhou Medical University from May 2018 to May 2019. The expression of genes involved in inflammasome complex including NLRC1, NLRC3, AIM2, NLRC4, ASC, caspase-1, IL-6, IL-18 and IL-1βwas determined via real-time PCR, immunohistochemistry and immunofluorescence. Measurement of NLRC4 level in serum was conducted by ELISA assay. The results showed that the NLRC4, ASC, caspase-1, IL-1β and IL-18 levels in fetal membrane, placental tissues and maternal serum were markedly higher in the PROM group than that in the control group. In conclusion, NLRC4 is a markedly up-regulated gene in TPROM fetal membrane tissue, suggesting that NLRC4 is involved in the occurrence and development of TPROM; NLRC4 levels in maternal blood serum are closely related to TPROM and have the potential to assist doctors in predicting and diagnosing PROM.

Virulence gene transcription, phylogroups, and antibiotic resistance of cervico-vaginal pathogenic E. coli in Mexico

The pathogenicity of Escherichia coli strains that cause cervico-vaginal infections (CVI) is due to the presence of several virulence genes. The objective of this study was to define the variability regarding the genotype of antibiotic resistance, the transcription profiles of virulence genes after in vitro infection of the vaginal cell line A431 and the phylogroup composition of a group of cervico-vaginal E. coli strains (CVEC). A total of 200 E. coli strains isolated from Mexican women with CVI from two medical units of the Mexican Institute of Social Security were analysed. E. coli strains and antibiotic resistance genes were identified using conventional polymerase chain reaction (PCR), and phylogroups were identified using multiplex PCR. Virulence gene transcription was measured through reverse-transcriptase real-time PCR after infection of the vaginal cell line A431. The most common antibiotic resistance genes among the CVEC strains were aac(3)II, TEM, dfrA1, sul1, and qnrA. The predominant phylogroup was B2. The genes most frequently transcribed in these strains were fimH, papC, irp2, iroN, kpsMTII, cnf1, and ompT, mainly in CVEC strains isolated from chronic and occasional vaginal infections. The strains showed a large diversity of transcription of the virulence genes phenotype and antibiotic resistance genotype, especially in the strains of phylogroups, B2, A, and D. The strains formed 2 large clusters, which contained several subclusters. The genetic diversity of CVEC strains was high. These strains have a large number of transcription patterns of virulence genes, and one-third of them carry three to seven antibiotic resistance genes.

Effect on perinatal outcome of prophylactic antibiotics in preterm prelabor rupture of membranes: network meta-analysis of randomized controlled trials

OBJECTIVES

Prophylactic antibiotics are recommended routinely for preterm prelabor rupture of membranes (PPROM), but there is an abundance of potential treatments and a paucity of comparative information. The aims of this network meta-analysis were to compare the efficiency of different antibiotic regimens on perinatal outcomes and to assess the quality of the current evidence.

METHODS

This was a network meta-analysis of randomized controlled trials comparing prophylactic antibiotics, or regimens of antibiotics, with each other or with placebo/no treatment, in women with PPROM. MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, US Registry of Clinical Trials ( www.ClinicalTrials.gov) and gray literature sources were searched. The primary outcomes were neonatal mortality and chorioamnionitis; secondary outcomes included other measures of perinatal morbidity. Relative effect sizes were estimated using risk ratios (RR) and the relative ranking of the interventions was obtained using cumulative ranking curves. The quality of evidence for the primary outcomes was assessed according to GRADE guidelines, adapted for network meta-analysis.

RESULTS

The analysis included 20 studies (7169 participants randomized to 15 therapeutic regimens). For the outcome of chorioamnionitis, clindamycin + gentamycin (network RR, 0.19 (95% CI, 0.05-0.83)), penicillin (RR, 0.31 (95% CI, 0.16-0.6)), ampicillin/sulbactam + amoxicillin/clavulanic acid (RR, 0.32 (95% CI, 0.12-0.92)), ampicillin (RR, 0.52 (95% CI, 0.34-0.81)) and erythromycin + ampicillin + amoxicillin (RR, 0.71 (95% CI, 0.55-0.92)) were superior to placebo/no treatment. Erythromycin was the only effective drug for neonatal sepsis (RR, 0.74 (95% CI, 0.56-0.97)). Clindamycin + gentamycin (RR, 0.32 (95% CI, 0.11-0.89)) and erythromycin + ampicillin + amoxicillin (RR, 0.83 (95% CI, 0.69-0.99)) were the only effective regimens for respiratory distress syndrome, whereas ampicillin (RR, 0.42 (95% CI, 0.20-0.92)) and penicillin (RR, 0.49 (95% CI, 0.25-0.96)) were effective in reducing the rates of Grade-3/4 intraventricular hemorrhage. None of the antibiotics appeared significantly more effective than placebo/no treatment in reducing the rates of neonatal death, perinatal death and necrotizing enterocolitis. No network RR could be estimated for neonatal intensive care unit admission. The overall quality of the evidence, according to GRADE guidelines, was moderate to very low, depending on the outcome and comparison.

CONCLUSIONS

Several antibiotics appear to be more effective than placebo/no treatment in reducing the rate of chorioamnionitis after PPROM. However, none of them is clearly and consistently superior compared to other antibiotics, and most are not superior to placebo/no treatment for other outcomes. The overall quality of the evidence is low and needs to be updated, as microbial resistance may have emerged for some antibiotics, while others are underrepresented in the existing evidence. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.