Open AccessEvaluation of a matrix-assisted laser desorption ionization-time of flight mass spectrometry assisted, selective broth method to screen for vancomycin-resistant enterococci in patients at high risk
Author(s) -
Tung Po Huang,
Susan Shin-Jung Lee,
Chia Chien Lee,
Chiu Yen Chen,
Fang Chen Chen,
Bao Chen Chen,
Cheng Len Sy,
Kang Wu
Publication year - 2017
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.0179455
Subject(s) - medicine , chromatography , agar , mass spectrometry , enterococcus , time of flight mass spectrometry , predictive value , vancomycin resistant enterococci , matrix assisted laser desorption/ionization , vancomycin , microbiology and biotechnology , incubation period , incubation , chemistry , bacteria , biology , desorption , antibiotics , staphylococcus aureus , ionization , ion , genetics , organic chemistry , adsorption , biochemistry
Background Bile esculin azide with vancomycin (BEAV) medium is a sensitive, but slightly less specific method for vancomycin-resistant enterococci (VRE) screening. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid method for identification of clinical pathogens. This study aimed to assess the performance of a novel combination screening test for VRE, using BEAV broth combined with MALDI-TOF MS. Materials and methods Clinical specimens were collected from patients at risk of VRE carriage, and tested by the novel combination method, using selective BEAV broth culture method followed by MALDI-TOF MS identification (SBEAVM). The reference method used for comparison was the ChromID VRE agar method. Results A total of 135 specimens were collected from 78 patients, and 63 specimens tested positive for VRE positive using the ChromID VRE method (positive rate 46.7%). The sensitivity, specificity, positive predictive value, and negative predictive value of SBEAVM method after an incubation period of 28 hours were 93.7%, 90.3%, 89.4%, and 94.2%, respectively. The SBEAVM method when compared to the ChromID VRE method had a shorter turnaround time (29 vs. 48–72 hours) and lower laboratory cost ($2.11 vs. $3.23 per test). Conclusions This study demonstrates that SBEAVM is a rapid, inexpensive, and accurate method for use in VRE screening.