Recent Changes in Bacteremia in Children at Juntendo University Urayasu Hospital

Abstract

Objective: This study was performed to investigate changes in bacteremia in children at Juntendo University Urayasu Hospital. Materials: A total of 10,487 blood culture specimens were examined from 3,916 children who were admitted to the Department of Pediatrics, Juntendo University Urayasu Hospital and underwent blood cultures from January 2006 to December 2014. Methods: Results for blood culture-positive children were compared before and after introduction of Haemophilus influenzae type b (Hib) vaccine (December 2008) and Streptococcus pneumoniae vaccine (February 2010), based on a retrospective analysis of a bacterial laboratory database. Results: A total of 94 patients had significant bacteria isolated from blood culture, giving a detection rate of 2.4%. Based on annual changes in the number of blood culture-positive patients aged 1 month or older, the number of Streptococcus pneumoniae-positive patients significantly decreased after 2010 and the number of Hib-positive patients reached a peak in 2008 and subsequently decreased. The major cause of fever without source in patients aged 1 month or older was Streptococcus pneumoniae until 2010, but subsequently changed to other bacteria that were unrelated to the vaccines. Conclusions: Introduction of Hib vaccine and Streptococcus pneumoniae vaccine significantly decreased both the number of cases of bacteremia in children and the incidence of invasive infections caused by Hib and Streptococcus pneumoniae. However, serotype replacement should be noted as a growing concern.