Comparison of antibiotic regimens in preterm premature rupture of membranes: neonatal morbidity and 2-year follow-up of neurologic outcome

Efficacy of prophylactic antibiotics for preterm premature rupture of membranes: a systematic review and network meta-analysis

OBJECTIVE

Various prophylactic antibiotic regimens are used in the management of preterm premature rupture of membranes. We investigated the efficacy and safety of these regimens in terms of maternal and neonatal outcomes.

DATA SOURCES

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from inception to July 20, 2021.

STUDY ELIGIBILITY CRITERIA

We included randomized controlled trials involving pregnant women with preterm premature rupture of membranes before 37 weeks of gestation and a comparison of ≥2 of the following 10 antibiotic regimens: control/placebo, erythromycin, clindamycin, clindamycin plus gentamicin, penicillins, cephalosporins, co-amoxiclav, co-amoxiclav plus erythromycin, aminopenicillins plus macrolides, and cephalosporins plus macrolides.

METHODS

Two investigators independently extracted published data and assessed the risk of bias with a standard procedure following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Network meta-analysis was conducted using the random-effects model.

RESULTS

A total of 23 studies that recruited a total of 7671 pregnant women were included. Only penicillins (odds ratio, 0.46; 95% confidence interval, 0.27-0.77) had significantly superior effectiveness for maternal chorioamnionitis. Clindamycin plus gentamicin reduced the risk of clinical chorioamnionitis, with borderline significance (odds ratio, 0.16; 95% confidence interval, 0.03-1.00). By contrast, clindamycin alone increased the risk of maternal infection. For cesarean delivery, no significant differences were noted among these regimens.

CONCLUSION

Penicillins remain the recommended antibiotic regimen for reducing maternal clinical chorioamnionitis. The alternative regimen includes clindamycin plus gentamicin. Clindamycin should not be used alone.

A randomized clinical trial of antibiotic treatment duration in preterm premature rupture of membranes: 7 days vs until delivery

BACKGROUND

Antibiotic treatment in preterm premature rupture of membranes can prolong the interval from membrane rupture to delivery and improve neonatal outcomes. However, the duration of antibiotic treatment for preterm premature rupture of membranes has been rarely compared in prospective studies.

OBJECTIVE

This study aimed to investigate the optimal duration of antibiotic treatment for premature rupture of membranes. We performed a randomized controlled trial comparing neonatal morbidity and infantile neurologic outcomes between 2 groups of patients with preterm premature rupture of membranes who received antibiotic treatment for 7 days or until delivery, respectively.

STUDY DESIGN

This prospective randomized study included patients who were diagnosed with preterm premature rupture of membranes between 22+0 weeks and 33+6 weeks of gestation. The enrolled patients were randomly assigned to receive intravenous cefazolin (1 g dosage every 12 hours) and oral clarithromycin (500 mg dosage every 12 hours) either for 7 days or until delivery. The study protocol was registered at ClinicalTrials.gov under identifier NCT01503606. The primary outcome was a neonatal composite morbidity, and the secondary outcome was neurologic outcomes at 12 months of corrected age. We enrolled 151 patients and allocated 75 and 76 of them to the 7-day and until-delivery groups, respectively. Analysis was done by per protocol.

RESULTS

After excluding cases lost to follow-up and those with protocol violations, 63 (7-day regimen) and 61 (until-delivery regimen) patients with preterm premature rupture of membranes and their babies were compared. There was no significant difference in the pregnancy outcomes, including gestational age at delivery and the interval from rupture of membranes to delivery, between the 2 groups. Among the neonatal outcomes, bronchopulmonary dysplasia, intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis, and proven neonatal sepsis did not differ between the groups. However, the rates of respiratory distress syndrome (32.8% vs 50.8%; P=.039) and composite neonatal morbidities (34.4% vs 53.9%; P=.026) were lower in the until-delivery group than in the 7-day group. This difference remained statistically significant after a multivariable analysis adjusting for maternal age, twin pregnancy, antenatal corticosteroids treatment, gestational age at delivery, interval from rupture of membranes to delivery, and clinical chorioamnionitis. Infantile neurologic outcomes were evaluated in 71.4% of the babies discharged alive and did not differ between the groups.

CONCLUSION

Overall, the until-delivery regimen of cefazolin and clarithromycin in preterm premature rupture of membranes led to a lower incidence of composite neonatal morbidity and respiratory distress syndrome than the 7-day regimen, and both regimens otherwise showed similar individual neonatal morbidities and infantile neurologic outcomes.

The Management of Pregnancy Complicated with the Previable Preterm and Preterm Premature Rupture of the Membranes: What about a Limit of Neonatal Viability?—A Review

Preterm premature rupture of the membranes (PPROM) at the limit of viability is associated with low neonatal survival rates and a high rate of neonatal complications in survivors. It carries a major risk of maternal morbidity and mortality. The limit of viability can be defined as the earliest stage of fetal maturity when a fetus has a reasonable chance, although not a high likelihood, for extra-uterine survival. The study reviews available data on preventing preterm delivery caused by the previable PPROM, pregnancy latency, therapeutic options including the use of antibiotics and steroids, neonatal outcomes, and future directions and opportunities.

Developing a Core Outcome Set for the Evaluation of Antibiotic Use in Prelabor Rupture of Membranes: A Systematic Review and Semi-Structured Interview

Background: Prelabor rupture of membranes (PROM) is associated with maternal and neonatal infections. Although guidelines suggest prophylactic antibiotics for pregnant women with PROM, the optimal antibiotic regimen remains controversial. Synthesizing the data from different studies is challenging due to variations in reported outcomes.

Objective: This study aimed to form the initial list of outcomes for the core outcome set (COS) that evaluates antibiotic use in PROM by identifying all existing outcomes and patients’ views.

Methods: Relevant studies were identified by searching PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang, and VIP databases. We also screened the references of the included studies as a supplementary search. We extracted basic information from the articles and the outcomes. Two reviewers independently selected the studies, extracted the data, extracted the outcomes, and grouped them into domains. Then, semi-structured interviews based on the potential factors collected by the systematic review were conducted at West China Second Hospital of Sichuan University. Pregnant women who met the diagnostic criteria for PROM were enrolled. Participants reported their concerns about the outcomes. Two researchers identified the pregnant women’s concerns.

Results: A total of 90 studies were enrolled in this systematic review. The median outcomes in the included studies was 7 (1–31), and 109 different unique outcomes were identified. Pre-term PROM (PPROM) had 97 outcomes, and term PROM (TPROM) had 70 outcomes. The classification and order of the core outcome domains of PPROM and TPROM were consistent. The physiological domain was the most common for PPROM and TPROM outcomes. Furthermore, 35.1 and 57.1% outcomes were only reported once in PPROM and TPROM studies, respectively. Thirty pregnant women participated in the semi-structured interviews; 10 outcomes were extracted after normalized, and the outcomes were reported in the systematic review. However, studies rarely reported pregnant women’s concerns.

Conclusion: There was considerable inconsistency in outcomes selection and reporting in studies about antibiotics in PROM. An initial core outcomes set for antibiotics in PROM was formed.

Optimized Clustering Algorithm for Comparative Analysis of Different Prenatal Corticosteroid Neurological Deficits in Premature Infants through Magnetic Reasoning Imaging (MRI)

Objective

This study aimed to explore the application of different prenatal corticosteroids in the assessment of neurological deficits and prognosis in premature infants through Magnetic Reasoning Imaging (MRI) under optimized cluster algorithm.

Methods

100 pregnant women with threatened preterm labor were retrospectively analyzed, in which 38 pregnant women with lasting threatened preterm labor (group A) were treated with multiple courses of antenatal corticosteroids (dexamethasone treatment) and 62 cases of pregnant women with threatened preterm labor (group B) were treated with single course of dexamethasone treatment. Craniocerebral MRI images based on optimal clustering algorithm were used to examine neonates. Neonatal hypoxic-ischemic encephalopathy (HIE) rate, serum neuron-specific enolase (NSE) concentration, neonatal behavioral neurological score (NBNA), respiratory distress syndrome (RDS) rate, perinatal mortality, neonatal birth weight, and maternal complications rate of two groups were compared.

Results

Compared with other traditional image segmentation algorithms, this algorithm had the best segmentation effect, the shortest running time (1.43 s), the least number of iterations (5 times), and the highest segmentation accuracy (97.98%). There was no significant difference in the HIE rate, serum NSE concentration, NBNA score, RDS score, and perinatal mortality in group A and group B (P > 0.05). Compared with group B, neonates' body weight in group A was decreased, while the maternal complication rate in group A was increased (P < 0.05).

Conclusion

MRI images based on optimized clustering algorithm can be used in the diagnosis of neonatal hypoxic-ischemic encephalopathy. There is no significant difference in the application of different antenatal corticosteroids affecting premature nerve function defect and prognosis, but multiple courses of antenatal corticosteroids can affect neonatal body mass and increased maternal complications to a certain extent; therefore, before threatened premature delivery treatment, the pros and cons of multiple courses of antenatal corticosteroids should fully be considered and in the treatment, measures should be actively taken to alleviate the side effect.

Maternal azithromycin therapy for Ureaplasma parvum intraamniotic infection improves fetal hemodynamics in a nonhuman primate model

BACKGROUND

Ureaplasma parvum infection is a prevalent cause of intrauterine infection associated with preterm birth, preterm premature rupture of membranes, fetal inflammatory response syndrome, and adverse postnatal sequelae. Elucidation of diagnostic and treatment strategies for infection-associated preterm labor may improve perinatal and long-term outcomes for these cases.

OBJECTIVE

This study assessed the effect of intraamniotic Ureaplasma infection on fetal hemodynamic and cardiac function and the effect of maternal antibiotic treatment on these outcomes.

STUDY DESIGN

Chronically catheterized pregnant rhesus monkeys were assigned to control (n=6), intraamniotic inoculation with Ureaplasma parvum (107 colony-forming units/mL, n=15), and intraamniotic infection plus azithromycin treatment (12.5 mg/kg twice a day intravenously, n=8) groups. At approximately 135 days' gestation (term=165 days), pulsed and color Doppler ultrasonography was used to obtain measurements of fetal hemodynamics (pulsatility index of umbilical artery, ductus venosus, descending aorta, ductus arteriosus, aortic isthmus, right pulmonary artery, middle cerebral artery and cerebroplacental ratio, and left and right ventricular cardiac outputs) and cardiac function (ratio of peak early vs late transmitral flow velocity [marker of ventricular function], Tei index [myocardial performance index]). These indices were stratified by amniotic fluid proinflammatory mediator levels and cardiac histology.

RESULTS

Umbilical and fetal pulmonary artery vascular impedances were significantly increased in animals from the intraamniotic inoculation with Ureaplasma parvum group (P<.05). Azithromycin treatment restored values to control levels. Amniotic fluid prostaglandin F2 alpha levels were significantly higher in animals with abnormal umbilical artery pulsatility index (>1.1) than in those with normal blood flow (P<.05; Spearman ρ=0.6, P<.05). In the intraamniotic inoculation with Ureaplasma parvum group, left ventricular cardiac output was significantly decreased (P<.001), and more animals had abnormal right-to-left ventricular cardiac output ratios (defined as >1.6, P<.05). Amniotic fluid interleukin-6 concentrations were elevated in cases of abnormal right-to-left ventricular cardiac output ratios compared with those in normal cases (P<.05).

CONCLUSION

Fetal hemodynamic alterations were associated with intraamniotic Ureaplasma infection and ameliorated after maternal antibiotic treatment. Doppler ultrasonographic measurements merit continuing investigation as a diagnostic method to identify fetal cardiovascular and hemodynamic compromise associated with intrauterine infection or inflammation and in the evaluation of therapeutic interventions or clinical management of preterm labor.

A new rapid bedside test to diagnose and monitor intraamniotic inflammation in preterm PROM using transcervically collected fluid

BACKGROUND

Microbial invasion of the amniotic cavity, a clinical condition present in approximately 50% of patients with preterm prelabor rupture of membranes, is often associated with intraamniotic inflammation, a risk factor for a short admission-to-delivery interval, early preterm delivery, and neonatal complications. We previously developed a transcervical amniotic fluid collector, the device that allows the collection of fluid noninvasively from the cervical canal when membrane rupture occurs.

OBJECTIVE

This study was designed to determine whether rapid analysis of an interleukin-8 concentration in fluid obtained noninvasively by the transcervical amniotic fluid collector can be used to assess the risk of intraamniotic inflammation. We also compared the diagnostic performance of this point-of-care test for interleukin-8 in transcervically obtained fluid to that of a white blood cell count determined in amniotic fluid retrieved by transabdominal amniocentesis.

STUDY DESIGN

This prospective cohort study was conducted between October 2011 and April 2017. Fluid was retrieved through both transabdominal amniocentesis and the use of a transcervical amniotic fluid collector within 24 hours of amniocentesis in patients with a singleton pregnancy and preterm prelabor rupture of the membranes (16-35 weeks of gestation). Amniotic fluid obtained via amniocentesis was cultured for aerobic and anaerobic bacteria and genital mycoplasmas; a white blood cell count was also measured in amniotic fluid. Intraamniotic infection was diagnosed when microorganisms were identified by the cultivation of amniotic fluid. Intraamniotic inflammation was defined as an elevated amniotic fluid matrix metalloproteinase-8 concentration (>23 ng/mL) assayed by enzyme-linked immunosorbent assay. Interleukin-8 in cervical fluid obtained by the collector was measured by the point-of-care test that used a test strip and scanner based on the fluorescence immunochromatographic analysis in 2019. The diagnostic indices, predictive values, and likelihood ratios of the 2 different tests were calculated.

RESULTS

First, interleukin-8 concentration ≥9.5 ng/mL in cervical fluid, determined by the point-of-care test, was at the knee of the receiver operating characteristic curve analysis and had a sensitivity of 98% (56/57; 95% confidence interval, 91-99.96%), specificity of 74% (40/54; 95% confidence interval, 60-85%), positive predictive value of 80% (56/70; 95% confidence interval, 72-86%), negative predictive value of 98% (40/41; 95% confidence interval, 85-99.6%), positive likelihood ratio of 3.79 (95% confidence interval, 2.41-5.96), and negative likelihood ratio of 0.02 (95% confidence interval, 0.003-0.17) in the identification of intraamniotic inflammation; a concentration of matrix metalloproteinase-8 >23 ng/mL by enzyme-linked immunosorbent assay had a prevalence of 51% (57/111). Second, a cervical fluid interleukin-8 concentration ≥9.5 ng/mL had significantly higher sensitivity than a transabdominally obtained amniotic fluid white blood cell count (≥19 cells/mm³) in the identification of intraamniotic inflammation (sensitivity: 98% [95% confidence interval, 91-99.96%] vs 84% [95% confidence interval, 72-93%]; P<.05; specificity: 74% [95% confidence interval, 60-85%] vs 76% [95% confidence interval, 62-87%); positive and negative predictive values: 80% [95% confidence interval, 72-86%] and 98% [95% confidence interval, 85-99.6%] vs 79% [95% confidence interval, 69-86%] and 82% [95% confidence interval, 71-89%]) and in the identification of intraamniotic inflammation/infection (gold standard: positive culture for bacteria or a matrix metalloproteinase-8 >23 ng/mL; sensitivity: 91% [95% confidence interval, 82-97%] vs 75% [95% confidence interval, 63-85%]; P<.05).

CONCLUSION

The point-of-care test was predictive of intraamniotic inflammation, based on the determination of interleukin-8 in fluid retrieved by a transcervical amniotic fluid collector. Therefore, the analysis of cervically obtained fluid by such point-of-care test may be used to noninvasively monitor intraamniotic inflammation in patients with preterm prelabor rupture of membranes.

Erythromycin compared to amoxicillin and azithromycin for antimicrobial prophylaxis for preterm premature rupture of the membranes: a retrospective study

Antimicrobial prophylaxis is widely recommended for pregnant women who have preterm premature rupture of the membranes. Erythromycin prophylaxis was used during an initial period (control) and then changed to intravenous amoxicillin for 48 h, followed by 5 days of oral amoxicillin along with a single dose of azithromycin (case). Healthcare records were reviewed retrospectively. The primary outcome was latency (between membrane rupture and delivery) and the secondary outcomes were mode of delivery, maternal high dependency unit (HDU) admission, and several laboratory parameters. There were 78 women in the case group (amoxicillin and azithromycin) and controls were selected on a 1:1 ratio. There was no statistically significant difference between cases and controls with respect to group B Streptococcus or E.coli carriage, previous preterm birth, assissted fertility and parity. No babies had a positive blood culture with Group B Streptococcus. There was a longer latency to delivery for those prescribed amoxicillin and azithromycin (median = 5.5 days), compared with controls on erythromycin (median = 2 days, p < .001). There was no difference in the mode of delivery or maternal HDU admission. Given the potential sequelae of preterm birth, this warrants further prospective investigation in a randomised control trial.IMPACT STATEMENTWhat is already known on this subject? Antimicrobial prophylaxis is recommended for women who have preterm premature rupture of the membranes (PPROM). It has been shown to increase latency of delivery. However there are different regimens recommended in North America (amoxicillin and a macrolide) and the United Kingdom (macrolide monotherapy).What do the results of this study add? This study has shown that in our population, women who were prescribed the PPROM regimen of amoxicillin with azithromycin had a longer median latency from time of rupture of membranes to delivery, than women in a historical control group who were prescribed erythromycin monotherapy.What are the implications of these findings for clinical practice and/or further research? This retrospective study has shown that there may be a difference in latency between different antimicrobial prophylaxis regimens for PPROM. A randomised control trial, with sufficient patient numbers, is needed to determine the best regimen for prophylaxis, and would allow harmonisation of international guidelines.

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.