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bioRxiv · 10.1101/510107

Automation for the identification of Pseudomonas aeruginosa: Comparison of TDR-300B, VITEK(R)2, and VITEK(R)-MS

Abstract

Quick and precise methods have always been needed in the medical field to correctly identify the agent of infection. Automated systems for diagnosis of infectious pathogen such Pseudomonas aeruginosa from critical patients with infections in the Intensive Care Unit is essential. This study aimed to compare the capability of automated biochemistry-based identification system, TDR-300B and VITEK(R)2, to the one of Matrix-Assisted Laser Desorption/Ionization - Time of Flight (MALDI-TOF), VITEK(R)-MS, in the identification of P. aeruginosa.\n\nSamples were P. aeruginosa isolates collection from Laboratory of Microbiology, Faculty of Medicine and Health Science UNIKA Atma Jaya. These isolates were refreshed; one single colony of oxidase-positive Gram-negative rods was further inoculated in TDR-300B NF-64 cards and VITEK(R)2 GN cassettes. The bacterial identification was also carried out using VITEK(R)-MS as gold-standard. Positivity of TDR-300B and VITEK(R)2 in the identification of P. aeruginosa was 87.09% (27/31) and 90.32% (28/31) in the species level, and 87.09%, 96.77% in the genus level respectively. The congruity of TDR-300B/ VITEK(R)2 in the species and genus level was 83.87% and 87.09%. When compared to VITEK(R)-MS, congruence of VITEK(R)2 was 93.30% (24/26) and TDR-300B was 80.76% (21/26). Sensitivity value for TDR-300B and VITEK(R)2 was high, 95.45% and 100%, positive predictive value and accuracy were lower in TDR-300B than VITEK(R)2; Fisher exact value was >0.05, thus there were no significant differences in the capability of TDR-300B and VITEK(R)2 in the identification of P. aeruginosa.

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BibTeXRIS

Moehario, L. H., Boestami, H. P., Edbert, D., Tjoa, E., Robertus, T.. 2019-01-04. Automation for the identification of Pseudomonas aeruginosa: Comparison of TDR-300B, VITEK(R)2, and VITEK(R)-MS. https://doi.org/10.1101/510107

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