Background: Invasive group B streptococcal (GBS) disease causes considerable morbidity and mortality in young infants, and 18% of GBS-meningitis survivors have moderate-to-severe neurodevelopmental impairment. However, there is a paucity of data regarding neurologic impairment following GBS sepsis.
Methods: A case-control study was undertaken in infants at 3 secondary-tertiary hospitals in Johannesburg, South Africa. Neurodevelopmental assessments were done at 1 year of age using the Denver II Developmental screening tool. A case was defined as isolation of GBS from blood or cerebrospinal fluid in infants less than 90 days of age. Three healthy controls (range: 1-6) were matched to maternal age, maternal HIV-infection status, gestational age and timing of enrollment.
Results: Of 122 invasive GBS cases, 78 (63.9%) had sepsis and 44 (36.1%) meningitis. Twenty-two (18%) invasive GBS cases (17 of 78; 21.8% with sepsis and 5 of 44; 11.4% with meningitis) died during the course of hospitalization, and a further 2 (1.6%; 1 sepsis and 1 meningitis case) died by 1 year of age. Five (1.1%) of 449 controls died by 1 year of age. Of the 45 GBS sepsis cases and 141 matched controls followed through to 1 year of age, 11 (24.4%) cases (3 with moderate-to-severe impairment) and 10 (7.1%) controls had an abnormal Denver score with an adjusted (for gender) odds ratio of 3.51; 95% confidence interval (CI): 1.23-10.04; P = 0.019. Four (20%) of the 20 GBS meningitis cases compared with 1 (1.5%) control had neurologic impairment at 1-year of age (aOR: 8.29; 95% CI: 0.88-78.3; P = 0.065) CONCLUSION:: In this setting, invasive GBS disease is associated with a high mortality. Infant survivors of invasive GBS sepsis compared with controls had 3.5-fold greater odds of neurologic impairment by 1 year of age. This corroborates the need for strategies to prevent invasive GBS disease.