Incidence and clinical characteristics of invasive group B streptococcal disease of young infants in Guangzhou

Abstract

Objective To investigate the incidence and clinical features of invasive group B streptococcus (GBS) infection of young infants less than 3 months old in Guangzhou in order to evaluate the importance of preventive measures. Methods All infants born in Guangzhou Women and Children′s Medical Center from January 2011 to December 2014 formed the baseline population, while infants aged 0-89 days from whom an isolate was derived from normally sterile body site with any signs of clinical disease were included in this study.Through database searches, information of identified patients were reviewed and patients′ data were recorded on a standardized data collection form.The data were used for statistical analysis.Patients were divided into early-onset disease (EOD) (0-6 days) and late-onset disease (LOD) (7-89 days) according to their first positive culture occurrence time. Results Among the 62 928 alive-births, 32 cases of GBS infection were confirmed.There were 20 cases of early-onset infection, 12 cases of late-onset.Among infants with EOD, 7 cases were diagnosed as sepsis complicated with pneumonia, 6 cases were complicated with meningitis, respiratory syndrome (13 cases), fever (6 cases) and at least one of perinatal risk factors (12 cases) were recorded. In late-onset cases, 6 cases manifested as sepsis, 5 cases as sepsis associated with meningitis, 10 cases with fever as the initial manifestation and 4 cases accompanied by neurological symptoms.All invasive GBS strains were susceptible to Penicillin, Vancomycin and Linezolid; 24 isolates(75.0%) were resistant to Erythromycin and 14 (43.8%)resistant to Clindamycin, and the resistance of isolates to both drugs were increased year by year.Three cases died of early-onset infection, and the case fatality was 15.0%, which was much higher than that of LOD (0). The average hospital stay was 15 days (1-42 days) and 31 days (7-133 days), respectively.There was 1 case(5.9%) of EOD that had the sequelae of nervous system, and 1 case (8.3%)of LOD had hearing impairment. Conclusions The incidence of invasive GBS among young infants less than 3 months old in Guangzhou is apparently higher than most Asian countries.Clinical attention should be paid to the perinatal risk factors, and early diagnosis and treatment with sensitive antibiotics is essential and effective. Key words: Infant, newborn; Group B streptococcus; Incidence; Sepsis; Meningitis