Epidemiology and Prevalence of Bloodstream Infections in a Regional Hospital in Northern Taiwan During 2008–2013

Abstract

Background Diagnosing bloodstream infections (BSIs) is a critical function of clinical microbiology laboratories. To reveal the prevalence of BSIs in a hospital in Northern Taiwan, which was established in July 2008, we investigated the clinical characteristics of patients with positive blood cultures from July 2008 to December 2013. Methods The medical records of the patients were retrospectively reviewed. In total, 104,641 blood culture sets were collected and analyzed. Results Microorganisms grew on 10.28% of these sets, as follows: 5.48% exhibited growth of a single microorganism; 1.56% exhibited growth of more than one microorganism; and 3.24% exhibited growth of contaminants. Furthermore, 5739 monomicrobial isolates included: Gram-positive cocci (22.02%); Enterobacteriaceae (56.51%); glucose nonfermentative Gram-negative bacteria (7.27%); yeast (6.22%); and anaerobic bacteria (6.64%). Most microorganisms were identified as follows: Escherichia coli (33.80%); Staphylococcus aureus (14.20%); Klebsiella pneumoniae (11.41%); Pseudomonas aeruginosa (3.17%); and the Acinetobacter calcoaceticus–Acinetobacter baumannii (Acb) complex (2.68%). Furthermore, among infants aged ≤3 months, Group B Streptococcus (GBS) and S. aureus were the leading pathogens causing bacteremia, whereas among infants 3–12 months old and children 1–4 years old, Salmonella species were the leading pathogens causing bacteremia. The prevalence of Streptococcus pneumoniae increased from the 3–12-month-old age group and reached a peak in the 5–12-year-old age group. For patients aged >13 years, the most common pathogens were E. coli, S. aureus, and K. pneumoniae. Conclusion We propose that the types and prevalence of BSIs vary according to age group and exhibit substantial geographical differences.