Korean J Clin Microbiol.  2009 Sep;12(3):144-145. 10.5145/KJCM.2009.12.3.144.

Evaluation of the Vitek 2 AST-N055 Card for the Susceptibility Testing of Acinetobacter baumannii Isolates to Amikacin

• Park DJ
• Song W
• Kim TK
• Kim JS
• Kim HS
• Lee KM

• KMID: 1828587
• DOI: http://doi.org/10.5145/KJCM.2009.12.3.144

Abstract

We collected 76 clinical isolates of Acinetobacter baumannii (amikacin MIC by Vitek 2 AST-N055 card: < or =2microgram/mL, 11 isolates; 4microgram/mL, 19 isolates; 8microgram/ mL, 17 isolates; 16microgram/mL, 27 isolates; and > or =64microgram/ mL, 2 isolates) from a university hospital and evaluated the Vitek 2 AST-N055 card vs the broth microdilution as a reference method for testing susceptibility to amikacin. Vitek 2 AST-N055 card yielded very major errors in 15 isolates (19.7%) and minor errors in 26 isolates (34.2%). Of the 15 isolates shown very major errors, 14 had Vitek 2 MICs ranging from 8 to 16microgram/mL. The results of our study suggest strongly that it is unreliable to test the amikacin susceptibility by Vitek 2 AST-N055 card of A. baumannii with the Vitek 2 MICs ranging from 8 to 16microgram/mL. In those cases, another susceptibility test, such as broth microdilution (BMD), should be performed to confirm the results.

Keyword

Amikacin; Acinetobacter baumannii; Vitek 2

MeSH Terms

Acinetobacter
Acinetobacter baumannii
Amikacin
Amikacin

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