Prevention of early-onset Group B Streptococcal disease - the Northern Ireland experience

OBJECTIVES
To ascertain guideline adherence for prevention of Group B Streptococcal (GBS) neonatal infection and establish prevalence and outcomes in Northern Ireland (NI).

DESIGN
Retrospective observational study. SETTING Northern Ireland maternity units. POPULATION Using NI Health Information Systems the following were identified: (1) a cohort of women with one or more risk factors for GBS disease in 2009-2010, (2) all culture-positive cases of GBS in babies aged 0-89 days (2008-2010), (3) stillbirths due to GBS (2009-2010).

METHODS
Information was analysed for a 15% randomised sample of the available cases. Maternal and infant case notes were reviewed for confirmed cases of neonatal early onset GBS (EOGBS) during 2008-2010.

MAIN OUTCOME MEASURES
Adherence to the 2003 RCOG guideline on prevention of GBS disease (2009-2010). Number of neonatal GBS infections: antenatal risk factors, management and neonatal outcomes (2008-2010). The number of stillbirths related to GBS (2009-2010).

RESULTS
Five hundred and seventy-four women had one or more identifiable risk factors for GBS disease; intrapartum antibiotic prophylaxis (IAP) was administered in 42% of cases. Improved administration of IAP was noted in the presence of escalating risk factors. At best, guideline adherence was 50-70%. Forty-three neonates had proven early-onset Group B Streptococcal disease; 55.8% had maternal risk factors. Of the total identified cases, 25.5% received IAP. The total mortality rate was 11.46%. The incidence of EOGBS disease in NI was 0.57/1000 live births. CONCLUSIONS Prevalence of EOGBS is higher in NI than the UK as a whole. Risk factors are present in 55.8% of mothers; IAP does not prevent all cases of EOGBS.