Age and risk factors influence the microbial aetiology of bloodstream infection in children

Aim To study the aetiology of bloodstream infections (BSI) in children 0–17 years, the influence of age and underlying co-morbidity on BSI rate, distribution of pathogens and outcome; and to provide data on antimicrobial susceptibility patterns. Methods A retrospective population-based study. Data on blood cultures were collected at yearly intervals during 1998–2008. Information about risk factors, focal infection and outcome was retrieved from the patient charts. Results We identified 1097 BSI. The incidence of BSI was 0.4/1000. The age-specific incidence was 2.3/1000 in neonates (0–28 days old) and 0.2/1000 in the age group 6–17 years. Staphylococcus aureus was the most common pathogen. The number of species causing BSI in previously healthy children was lower compared with children with co-morbidity. Most children requiring intensive care had a serious underlying illness. Antimicrobial resistance was rare and did not influence outcome. The case-fatality rate was 14.4% in neonates, 5.4% in children with co-morbidity and 1.7% in previously healthy children. Conclusion Mortality from BSI is low, and a limited spectrum of pathogens is isolated from previously healthy children compared with children with co-morbidity. When choosing empirical therapy for suspected BSI, age and presence of risk factors should be taken into account.