Open AccessEvaluation of an Automated Rapid Diagnostic Assay for Detection of Gram-Negative Bacteria and Their Drug-Resistance Genes in Positive Blood Cultures
Author(s) -
Masayoshi Tojo,
Takahiro Fujita,
Yusuke Ainoda,
Maki Nagamatsu,
Kayoko Hayakawa,
Kazuhisa Mezaki,
Aki Sakurai,
Yoshinori Masui,
Hirohisa Yazaki,
Hiroshi Takahashi,
Tohru MiyoshiAkiyama,
Kyoichi Totsuka,
Teruo Kirikae,
Norio Ohmagari
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0094064
Subject(s) - klebsiella oxytoca , microbiology and biotechnology , citrobacter , klebsiella pneumoniae , acinetobacter , enterobacter , serratia marcescens , biology , blood culture , bacteria , acinetobacter baumannii , klebsiella , multiplex , pseudomonas aeruginosa , escherichia coli , antibiotics , gene , bioinformatics , biochemistry , genetics
We evaluated the performance of the Verigene Gram-Negative Blood Culture Nucleic Acid Test (BC-GN; Nanosphere, Northbrook, IL, USA), an automated multiplex assay for rapid identification of positive blood cultures caused by 9 Gram-negative bacteria (GNB) and for detection of 9 genes associated with β-lactam resistance. The BC-GN assay can be performed directly from positive blood cultures with 5 minutes of hands-on and 2 hours of run time per sample. A total of 397 GNB positive blood cultures were analyzed using the BC-GN assay. Of the 397 samples, 295 were simulated samples prepared by inoculating GNB into blood culture bottles, and the remaining were clinical samples from 102 patients with positive blood cultures. Aliquots of the positive blood cultures were tested by the BC-GN assay. The results of bacterial identification between the BC-GN assay and standard laboratory methods were as follows: Acinetobacter spp. (39 isolates for the BC-GN assay/39 for the standard methods), Citrobacter spp. (7/7), Escherichia coli (87/87), Klebsiella oxytoca (13/13), and Proteus spp. (11/11); Enterobacter spp. (29/30); Klebsiella pneumoniae (62/72); Pseudomonas aeruginosa (124/125); and Serratia marcescens (18/21); respectively. From the 102 clinical samples, 104 bacterial species were identified with the BC-GN assay, whereas 110 were identified with the standard methods. The BC-GN assay also detected all β-lactam resistance genes tested (233 genes), including 54 bla CTX-M , 119 bla IMP , 8 bla KPC , 16 bla NDM , 24 bla OXA-23 , 1 bla OXA-24/40 , 1 bla OXA-48 , 4 bla OXA-58 , and 6 bla VIM . The data shows that the BC-GN assay provides rapid detection of GNB and β-lactam resistance genes in positive blood cultures and has the potential to contributing to optimal patient management by earlier detection of major antimicrobial resistance genes.