Neonatal group B streptococcal disease: incidence, presentation, and mortality

To ascertain the incidence, and compare the clinical characteristics, laboratory parameters, and immediate mortality of neonates with early-onset (symptomatic and asymptomatic) and late-onset group B streptococcal (GBS) disease.

A chart review of 81 neonates with GBS disease (either blood and/or cerebrospinal fluid culture-proven) born between 1995 and 2002 admitted to two tertiary care perinatal centers in Toronto was conducted. Clinical characteristics were compared for (1) asymptomatic early-onset, symptomatic early-onset, and late-onset GBS disease and (2) survivors and non-survivors.

The incidence of GBS disease was 1.13/1000 live births. One or more antepartum or intrapartum predisposing factors were recognized in 62% of cases. Early-onset was noted in 65 (80%) neonates (23 asymptomatic and 42 symptomatic). All full-term infants survived. The mortality was 6% and was confined to preterm neonates with early symptomatic disease who presented with shock and had thrombocytopenia.

Antepartum or intrapartum known predisposing risk factors of GBS disease were lacking in one third of patients. Patients who died were preterm infants in the early symptomatic group.