Intrapartum prophylaxis with ceftriaxone decreases rates of bacterial colonization and early-onset infection in newborns

Prevalence of early-onset neonatal infection among newborns of mothers with bacterial infection or colonization: a systematic review and meta-analysis

BACKGROUND

Although neonatal infections cause a significant proportion of deaths in the first week of life, little is known about the burden of neonatal disease originating from maternal infection or colonization globally. This paper describes the prevalence of vertical transmission--the percentage of newborns with neonatal infection among newborns exposed to maternal infection.

METHODS

We searched Pubmed, Embase, Scopus, Web of Science, Cochrane Library, and WHO Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection. Studies that measured prevalence of bacterial vertical transmission were included. Random effects meta-analyses were used to pool data to calculate prevalence estimates of vertical transmission.

RESULTS

122 studies met the inclusion criteria. Only seven studies (5.7%) were from very high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of infection (lab-confirmed, clinical signs), colonization, and risk factors of infection. The prevalence of early onset neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 17.2% (95%CI 6.5-27.9). The prevalence of neonatal lab-confirmed infection among newborns of colonized mothers was 0% (95% CI 0.0-0.0). The prevalence of neonatal surface colonization among newborns of colonized mothers ranged from 30.9-45.5% depending on the organism. The prevalence of neonatal lab-confirmed infection among newborns of mothers with risk factors (premature rupture of membranes, preterm premature rupture of membranes, prolonged rupture of membranes) ranged from 2.9-19.2% depending on the risk factor.

CONCLUSIONS

The prevalence of early-onset neonatal infection is high among newborns of mothers with infection or risk factors for infection. More high quality studies are needed particularly in high neonatal mortality settings to accurately estimate the prevalence of early-onset infection among newborns at risk.

Intrapartum antibiotics for known maternal Group B streptococcal colonization

BACKGROUND

Maternal colonization with group B streptococcus (GBS) during pregnancy increases the risk of neonatal infection by vertical transmission. Administration of intrapartum antibiotic prophylaxis (IAP) during labor has been associated with a reduction in early onset GBS disease (EOGBSD). However, treating all colonized women during labor exposes a large number of women and infants to possible adverse effects without benefit.

OBJECTIVES

To assess the effect of intrapartum antibiotics for maternal Group B haemolytic streptococci (GBS) colonization on mortality from any cause, from GBS infection and from organisms other than GBS.

SEARCH METHODS

We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 11 March 2014.

SELECTION CRITERIA

Randomized trials assessing the impact of maternal IAP on neonatal GBS infections were included.

DATA COLLECTION AND ANALYSIS

We independently assessed eligibility and quality of the studies.

MAIN RESULTS

We did not identify any new trials from the updated search so the results remain unchanged as follows.We included four trials involving 852 women.Three trials (involving 500 women) evaluating the effects of IAP versus no treatment were included. The use of IAP did not significantly reduce the incidence of all cause mortality, mortality from GBS infection or from infections caused by bacteria other than GBS. The incidence of early GBS infection was reduced with IAP compared to no treatment (risk ratio (RR) 0.17, 95% confidence interval (CI) 0.04 to 0.74, three trials, 488 infants; risk difference -0.04, 95% CI -0.07 to -0.01; number needed to treat to benefit 25, 95% CI 14 to 100, I² 0%). The incidence of LOD or sepsis from organisms other than GBS and puerperal infection was not significantly different between groups.One trial (involving 352 women) compared intrapartum ampicillin versus penicillin and reported no significant difference in neonatal or maternal outcomes.We found a high risk of bias for one or more key domains in the study methodology and execution.

AUTHORS' CONCLUSIONS

Intrapartum antibiotic prophylaxis appeared to reduce EOGBSD, but this result may well be due to bias as we found a high risk of bias for one or more key domains in the study methodology and execution. There is lack of evidence from well designed and conducted trials to recommend IAP to reduce neonatal EOGBSD.Ideally the effectiveness of IAP to reduce neonatal GBS infections should be studied in adequately sized double-blind controlled trials. The opportunity to conduct such trials has likely been lost, as practice guidelines (albeit without good evidence) have been introduced in many jurisdictions.

Prophylactic antibiotics for inhibiting preterm labour with intact membranes

BACKGROUND

The aetiology of preterm birth is complex and there is evidence that subclinical genital tract infection influences preterm labour in some women but the role of prophylactic antibiotic treatment in the management of preterm labour is controversial. Since rupture of the membranes is an important factor in the progression of preterm labour, it is important to see if the routine administration of antibiotics confers any benefit or causes harm, prior to membrane rupture.

OBJECTIVES

To assess the effects of prophylactic antibiotics administered to women in preterm labour with intact membranes, on maternal and neonatal outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 August 2013).

SELECTION CRITERIA

Randomised trials that compared antibiotic treatment with placebo or no treatment for women in preterm labour (between 20 and 36 weeks' gestation) with intact membranes.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial eligibility, and undertook quality assessment and data extraction. We contacted study authors for additional information. Results are presented using risk ratio (RR) for categorical data and mean difference (MD) for data measured on a continuous scale with their respective 95% confidence intervals (CI). The number needed to treat to benefit (NNTB) and the number needed to treat to harm (NNTH) was calculated where appropriate.

MAIN RESULTS

In this update (2013), with the addition of three trials (305 women), the large ORACLE II 2001 trial continues to dominate the results of this review. This review now includes a total of 14 studies randomising 7837 women. No significant difference was shown in perinatal or infant mortality for infants of women allocated to any prophylactic antibiotics compared with no antibiotics. However, an increase in neonatal deaths was shown for infants of women receiving any prophylactic antibiotics when compared with placebo (RR 1.57, 95% CI 1.03 to 2.40; NNTH 149, 95% CI 2500 to 61). No reduction in preterm birth or other clinically important short-term outcomes for the infant were shown.Long-term child outcomes to seven years of age were available for infants in the UK enrolled in the ORACLE II trial. Comparing any antibiotics with placebo, a marginally non-statistically significant increase was shown in any functional impairment (RR 1.10, 95% CI 0.99 to 1.23) and cerebral palsy (CP) (RR 1.82, 95% CI 0.99 to 3.34). In subgroup analysis, CP was statistically significantly increased for infants of women allocated to macrolide and beta-lactam antibiotics combined compared with placebo (RR 2.83, 95% CI 1.02 to 7.88; NNTH 35, 95% CI 333 to 9).Further, exposure to any macrolide antibiotics (including erythromycin alone or erythromycin plus co-amoxiclav) versus no macrolide antibiotics (including placebo and co-amoxiclav alone) was shown to increase neonatal death (RR 1.52, 95% CI 1.05 to 2.19; NNTH 139, 95% CI 1429 to 61), any functional impairment (RR 1.11, 95% CI 1.01 to 1.20; NNTH 24, 95% CI 263 to 13) and CP (RR 1.90, 95% CI 1.20 to 3.01; NNTH 64, 95% CI 286 to 29). Exposure to any beta-lactam (beta-lactam alone or in combination with macrolide antibiotics) versus no beta-lactam antibiotics resulted in more neonatal deaths (RR 1.51, 95% CI 1.06 to 2.15; NNTH 143, 95% CI 1250 to 63) and CP (RR 1.67, 95% CI 1.06 to 2.61; NNTH 79, 95% CI 909 to 33), however no difference was shown in functional impairment.Maternal infection was reduced with the use of any prophylactic antibiotics compared with placebo (RR 0.74, 95% CI 0.63 to 0.86; NNTB 34, 95% CI 24 to 63) and any beta-lactam compared with no beta-lactam antibiotics (RR 0.80, 95% CI 0.69 to 0.92; NNTB 47, 95% CI 31 to 119). However, caution should be exercised with this finding due to the possibility of bias shown by funnel plot asymmetry. Any beta-lactam compared with no beta-lactam antibiotics was associated with an increase in maternal adverse drug reaction (RR 1.61, 95% CI 1.02 to 2.54; NNTH 17, 95% CI 526 to 7).

AUTHORS' CONCLUSIONS

This review did not demonstrate any benefit in important neonatal outcomes with the use of prophylactic antibiotics for women in preterm labour with intact membranes, although maternal infection may be reduced. Of concern, is the finding of short- and longer-term harm for children of mothers exposed to antibiotics. The evidence supports not giving antibiotics routinely to women in preterm labour with intact membranes in the absence of overt signs of infection.Further research is required to develop sensitive markers of subclinical infection for women in preterm labour with intact membranes, as this is a group that might benefit from future novel interventions, including new modalities of antibiotic therapy. The results of this review demonstrate the need for future trials in the area of preterm birth to include assessment of long-term neurodevelopmental outcome.

Risk of early-onset neonatal infection with maternal infection or colonization: a global systematic review and meta-analysis

BACKGROUND

Neonatal infections cause a significant proportion of deaths in the first week of life, yet little is known about risk factors and pathways of transmission for early-onset neonatal sepsis globally. We aimed to estimate the risk of neonatal infection (excluding sexually transmitted diseases [STDs] or congenital infections) in the first seven days of life among newborns of mothers with bacterial infection or colonization during the intrapartum period.

METHODS AND FINDINGS

We searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, and the World Health Organization Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection published from January 1, 1960 to March 30, 2013. Studies were included that reported effect measures on the risk of neonatal infection among newborns exposed to maternal infection. Random effects meta-analyses were used to pool data and calculate the odds ratio estimates of risk of infection. Eighty-three studies met the inclusion criteria. Seven studies (8.4%) were from high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of laboratory-confirmed and clinical signs of infection, as well as for colonization and risk factors. The odds ratio for neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 6.6 (95% CI 3.9-11.2). Newborns of mothers with colonization had a 9.4 (95% CI 3.1-28.5) times higher odds of lab-confirmed infection than newborns of non-colonized mothers. Newborns of mothers with risk factors for infection (defined as prelabour rupture of membranes [PROM], preterm <37 weeks PROM, and prolonged ROM) had a 2.3 (95% CI 1.0-5.4) times higher odds of infection than newborns of mothers without risk factors.

CONCLUSIONS

Neonatal infection in the first week of life is associated with maternal infection and colonization. High-quality studies, particularly from settings with high neonatal mortality, are needed to determine whether targeting treatment of maternal infections or colonization, and/or prophylactic antibiotic treatment of newborns of high risk mothers, may prevent a significant proportion of early-onset neonatal sepsis. Please see later in the article for the Editors' Summary.

Intrapartum antibiotics for known maternal Group B streptococcal colonization

BACKGROUND

Maternal colonization with group B streptococcus (GBS) during pregnancy increases the risk of neonatal infection by vertical transmission. Administration of intrapartum antibiotic prophylaxis (IAP) during labor has been associated with a reduction in early onset GBS disease (EOGBSD). However, treating all colonized women during labor exposes a large number of women and infants to possible adverse effects without benefit.

OBJECTIVES

To assess the effect of IAP for maternal GBS colonization on neonatal: 1) all cause mortality and 2) morbidity from proven and probable EOGBSD, late onset GBS disease (LOD), maternal infectious outcomes and allergic reactions to antibiotics.

SEARCH METHODS

We updated the search of the Cochrane Pregnancy and Childbirth Group's Trials Register on 10 November 2012.

SELECTION CRITERIA

Randomized trials assessing the impact of maternal IAP on neonatal GBS infections were included.

DATA COLLECTION AND ANALYSIS

We independently assessed eligibility and quality of the studies.

MAIN RESULTS

We did not identify any new trials from the updated search so the results remain unchanged as follows.Three trials (involving 852 women) evaluating the effects of IAP versus no treatment were included. The risk of bias was high. The use of IAP did not significantly reduce the incidence of all cause mortality, mortality from GBS infection or from infections caused by bacteria other than GBS. The incidence of early GBS infection was reduced with IAP compared to no treatment (risk ratio 0.17, 95% confidence interval (CI) 0.04 to 0.74, three trials, 488 infants; risk difference -0.04, 95% CI -0.07 to -0.01; number needed to treat to benefit 25, 95% CI 14 to 100, I(2) 0%). The incidence of LOD or sepsis from organisms other than GBS and puerperal infection was not significantly different between groups.One trial (involving 352 women) compared intrapartum ampicillin versus penicillin and reported no significant difference in neonatal or maternal outcomes.

AUTHORS' CONCLUSIONS

Intrapartum antibiotic prophylaxis appeared to reduce EOGBSD, but this result may well be a result of bias as we found a high risk of bias for one or more key domains in the study methodology and execution. There is lack of evidence from well designed and conducted trials to recommend IAP to reduce neonatal EOGBSD.Ideally the effectiveness of IAP to reduce neonatal GBS infections should be studied in adequately sized double-blind controlled trials. The opportunity to conduct such trials has likely been lost, as practice guidelines (albeit without good evidence) have been introduced in many jurisdictions.

Intrapartum antibiotics for known maternal Group B streptococcal colonization

BACKGROUND

Maternal colonization with group B streptococcus (GBS) during pregnancy increases the risk of neonatal infection by vertical transmission. Administration of intrapartum antibiotic prophylaxis (IAP) during labor has been associated with a reduction in early onset GBS disease (EOGBSD). However, treating all colonized women during labor exposes a large number of women and infants to possible adverse effects without benefit.

OBJECTIVES

To assess the effect of IAP for maternal GBS colonization on neonatal: 1) all cause mortality and 2) morbidity from proven and probable EOGBSD, late onset GBS disease (LOD), maternal infectious outcomes and allergic reactions to antibiotics.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2009).

SELECTION CRITERIA

Randomized trials assessing the impact of maternal IAP on neonatal GBS infections were included.

DATA COLLECTION AND ANALYSIS

We independently assessed eligibility and quality of the studies.

MAIN RESULTS

Three trials (involving 852 women) evaluating the effects of IAP versus no treatment were included. The risk of bias was high. The use of IAP did not significantly reduce the incidence of all cause mortality, mortality from GBS infection or from infections caused by bacteria other than GBS. The incidence of early GBS infection was reduced with IAP compared to no treatment (risk ratio 0.17, 95% confidence interval (CI) 0.04 to 0.74, three trials, 488 infants; risk difference -0.04, 95% CI -0.07 to -0.01; number needed to treat to benefit 25, 95% CI 14 to 100, I(2) 0%). The incidence of LOD or sepsis from organisms other than GBS and puerperal infection was not significantly different between groups.One trial (involving 352 women) compared intrapartum ampicillin versus penicillin and reported no significant difference in neonatal or maternal outcomes.

AUTHORS' CONCLUSIONS

Intrapartum antibiotic prophylaxis appeared to reduce EOGBSD, but this result may well be a result of bias as we found a high risk of bias for one or more key domains in the study methodology and execution. There is lack of evidence from well designed and conducted trials to recommend IAP to reduce neonatal EOGBSD.Ideally the effectiveness of IAP to reduce neonatal GBS infections should be studied in adequately sized double-blind controlled trials. The opportunity to conduct such trials has likely been lost, as practice guidelines (albeit without good evidence) have been introduced in many jurisdictions.

Antibiotics for preterm labour with intact membranes

BACKGROUND

There may be a link between infection and preterm birth.

OBJECTIVES

Since rupture of the membranes is an important factor in the progression of preterm labour, it is important to see if antibiotics are of any benefit prior to membrane rupture. The objective of this review was to assess the effects of antibiotics administered to women in preterm labour with intact membranes, on maternal and neonatal outcomes.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and reference lists of articles. We contacted experts in the field.

SELECTION CRITERIA

Randomised trials which compared antibiotic treatment with placebo or no treatment for women in preterm labour (between 20 and 36 weeks gestation) with intact membranes.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed and data were extracted independently by two reviewers. Study authors were contacted for missing data.

MAIN RESULTS

Meta-analysis of the ten included trials demonstrated a statistically significant prolongation of pregnancy associated with the use of antibiotics (5. 4 days, 95% confidence interval (CI) 0.9- 9.8 days). Antibiotic treatment was also associated with a statistically significant reduction in maternal infection (odds ratio (OR) 0.59, 95% CI 0.36, 0.97) and neonatal necrotising enterocolitis (OR 0.33, 95% CI 0.13, 0.88). No statistically significant effect was detected on the neonatal outcomes of respiratory distress syndrome and neonatal sepsis, although there was a trend towards the latter (OR 0.67, 95% CI 0.42, 1.07). An increase in perinatal mortality was observed in the group receiving antibiotics (OR 3.36, 95% CI 1.21, 9.32).

REVIEWER'S CONCLUSIONS

Although a prolongation in time to delivery and a trend towards a reduction in neonatal sepsis was detected, this review fails to demonstrate a clear overall benefit from antibiotic treatment for preterm labour with intact membranes on neonatal outcomes and raises concerns about increased perinatal mortality for those who received antibiotics. This treatment cannot therefore be currently recommended for routine practice. Further research is required to identify a subgroup of women (and their babies) who are more likely to experience benefit from antibiotic treatment for preterm labour prior to membrane rupture, and to identify which antibiotic or combination of antibiotics is most effective. The results of the ongoing ORACLE trial should help resolve some of the uncertainties revealed by this review.

Prophylaxis of bacterial meningitis

A comprehensive review of all major agents causing bacterial meningitis--meningococcus of the groups A, B, C, W135, and Y, pneumococcus, and Haemophilus influenzae type B (Hib)--is done in terms of preventing them by chemoprophylaxis or vaccination. Some evidence suggests that the group B meningococcal disease may also be very likely preventable by a vaccine that is already available. Excellent Hib conjugates use a technique that is expected to revolutionize immunoprophylaxis against most meningococcal and pneumococcal diseases in the near future. Unfortunately, the high cost of conjugate vaccines restricts their use in many poor countries.