Routine culture-based screening versus risk-based management for the prevention of early-onset group B streptococcus disease in the neonate: a systematic review

Background: Early-onset group B streptococcus disease, recognized as the most common cause of early onset neonatal sepsis in developed countries, is transmitted vertically from the group B streptococcus carrier mother to the neonate in the peripartum. Accordingly, early-onset group B streptococcus disease is prevented by halting the transmission of the microorganism from the mother to the infant. Two main methods, routine culture-based screening and risk-based management, may be used in the identification of mothers requiring intrapartum antibiotic prophylaxis in labor. While there are advantages and disadvantages to each, there is limited high level evidence available as to which method is superior.

Objectives: To identify the effectiveness of risk-based management versus routine culture-based screening in the prevention of early-onset group B streptococcus disease in the neonate.

Types of participants: This review considered studies which treated pregnant women with intrapartum antibiotic prophylaxis following risk- and culture-based protocols for the prevention of early-onset group B streptococcus disease in the neonate. Types of intervention: This review considered studies that evaluated risk-based management against routine culture-based screening for the prevention of early-onset group B streptococcus disease in the neonate. Types of studies: This review looked for highest evidence available which in this case consisted of one quasi experimental study and eight comparative cohort studies with historical or concurrent control groups. Types of outcomes: Incidence of early-onset group B streptococcus disease in neonates as measured by positive group B streptococcus culture from an otherwise sterile site. Secondary outcomes include neonatal death due to group B streptococcus sepsis and percentage of women who received intrapartum antibiotic prophylaxis.

Search strategy: A multi-step search strategy was used to find studies which were limited to the English language and published between January 2000 and June 2013.

Methodological quality: The quality of the eligible studies was assessed independently by two reviewers using the Joanna Briggs Institute quality assessment tool for observational studies.

Data collection: Data was extracted using a standardized extraction tool from the Joanna Briggs Institute.

Data synthesis: Quantitative papers were, where possible, pooled for meta-analysis using Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument effect sizes expressed as odds ratio and their 95% confidence intervals were calculated. Heterogeneity was assessed statistically using the standard Chi-square.

Results: The results of this review come from nine studies published in peer reviewed journals. The treatment group consists of those screened as per the culture-based protocol, the control group the risk-based protocol. For combined term and preterm infants the odds of early-onset group B streptococcus disease for the treatment vs control groups is 0.45 (95% CI 0.37 to 0.53). The odds ratio in term infants is 0.45 (95% CI 0.36 to 0.57). Preterm infants are four times (OR 4.20 [95% CI 3.36 to 5.24]) more likely to develop early-onset group B streptococcus disease than term infants regardless of prevention technique. One study provides information on neonatal mortality in which there is one neonatal death in the risk-based cohort and none in the culture-based. The TRUNCATED AT 500 WORDS.