title: Algorithm for the identification of bacterial pathogens in positive blood cultures by real-time LightCycler polymerase chain reaction (PCR) with sequence-specific probes.
abstract: We developed real-time polymerase chain reaction (PCR) assays for rapid detection of the most common and clinically relevant bacteria in positive blood culture bottles, including Staphylococcus spp., S. epidermidis, S. aureus, Enterococcus spp. (including differentiation of E. faecalis and E. faecium), Streptococcus spp., Streptococcus agalactiae, Enterobacteriaceae, E. coli, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Acinetobacter spp., Bacteroides spp., Haemophilus influenzae, and Neisseria meningitidis. A total of 507 positive blood cultures were investigated according to a specific PCR algorithm based on the microscopic result of the blood culture, and the PCR results were compared to the culture results. Apart from-cross reactions between E. coli and Chryseomonas luteola and Enterococcus faecium and E. durans, the PCR assay correctly identified all bacteria in the blood cultures and did not show any false-positive results. Regarding blood cultures positive with a single species of bacteria (n = 474), 98.3% of all bacteria were correctly detected by the PCR algorithm within a few hours. However, in mixed infections, the sensitivity was lower. The PCR algorithm is well suited for rapid identification of the most common bacteria in positive blood cultures.
authors.affiliation: Department of Medical Microbiology and Hygiene, University of Ulm, Ulm, Germany. nele.wellinghausen@medizin.uni-ulm.de
authors.forename: Nele
authors.initials: N
authors.lastname: Wellinghausen
authors.forename: Beate
authors.initials: B
authors.lastname: Wirths
authors.forename: Axel R
authors.initials: AR
authors.lastname: Franz
authors.forename: Lothar
authors.initials: L
authors.lastname: Karolyi
authors.forename: Reinhard
authors.initials: R
authors.lastname: Marre
authors.forename: Udo
authors.initials: U
authors.lastname: Reischl
mesh_terms: D000465:Algorithms; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D015373:Bacterial Typing Techniques; D017931:DNA Primers; D005456:Fluorescent Dyes; D006090:Gram-Negative Bacteria / Q000145:classification / Q000235:genetics; D006094:Gram-Positive Bacteria / Q000145:classification / Q000235:genetics; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*
chemical_list: D017931:DNA Primers; D005456:Fluorescent Dyes