Invasive neonatal Streptococcus agalactiae infection in Slovenia, 2003–2013

Abstract

Background: Streptococcus agalactiae (group B streptococcus, GBS) is the leading cause of invasive neonatal infections in the developed world. We present epidemiological and clinical characteristics of invasive GBS disease among Slovenian neonates between 2003 and 2013. Methods: A retrospective cohort study was performed. Children aged 0–90 days with invasive GBS disease, born in Slovenia and hospitalized in the University Medical Centre Ljubljana were included. Cases were identified concurrently from (i) hospital and (ii) microbiological databases. Medical records from mothers and children were reviewed and relevant data extracted. The incidence rate was calculated based on the national vital statistics data and expressed per 1000 live births. Results: Altogether, 144 children were included in the analysis, 72.9 % (n = 105) based on hospital database and 27.1 % (n = 39) based on microbiological database. Among them, 47.9 % (n = 69) were girls and 52.1 % (n = 75) boys. Among the cases with available data, 54.5 % (n = 73) were born at term and 45.5 % (n = 61) were preterm. Early-onset disease (0–6 days) was present in 74.3 % (n = 107) of patients; 95.3 % (n = 102) of them became ill during the first 3 days of life. Late-onset disease (7–90 days) was present in 25.7 % (n = 37) of patients. Outcome data was available for 134 children. Neonatal mortality rate was 4.5 % (n = 6). Periventricular leukomalacia (PVL) or intraventricular haemorrhages Grade III/IV (IVH 3/4) were detected in 17.9 % (n = 24). Severe outcomes (death or PVL or IVH 3/4) were detected in 22.4 % (n = 30) children. Cumulative incidence rate was 0.72/1000 live births; 0.53/1000 for early-onset and 0.18/1000 for late-onset disease. Risk factors for early-onset disease were present in 47.9 % (n = 68) mothers in labour. Intrapartum antibiotic prophylaxis was delivered to 16.9 % (n = 24) of mothers. Conclusions: High incidence of invasive neonatal GBS disease was detected in Slovenia. Although low mortality was observed, brain pathology concordant with long-term adverse outcome was confirmed in a high proportion of patients. The application of intrapartum antibiotic prophylaxis in cases of known risk factors was suboptimal, especially among preterm deliveries. Approximately half of the patients were born to mothers without any risk factors. A comprehensive national strategy for the prevention of invasive GBS disease is warranted in Slovenia.

Keywords

• Streptococcus agalactiae
• invazivna neonatalna okužba
• incidenca
• preventiva
• Slovenija