Abstract:

Objective To evaluate the performance of Vitek 2 Compact AST-N334,AST-N335,AST-P639 Chinese antimicrobial susceptibility test（AST） cards. Methods Totally,73 strains of quality control bacteria were collected from authoritative institutions and 112 strains of clinical bacteria were randomly collected from hospitalized patients in Huashan Hospital from January to June 2018. The reliability of AST cards was evaluated,the accuracy of AST cards and broth microdilution method（BMM） was evaluated by quality control bacteria and AST results provided by authoritative institutions. The accuracy of AST cards in the detection of antibiotic resistance diversity was evaluated,and the accuracy of AST cards was evaluated by the clinical bacteria using BMM results as the reference standard. Results With the results of AST provided by the authoritative institutions as the reference standard,the percentages of AST-N334,AST-N335 and AST-P639 categorical agreement（CA） were 95.5%（126/132）,96.8%（179/185） and 99.5%（182/183）. With the results of BMM as the reference standard,the percentage of AST-N334 essential agreement（EA） was 88.4% （961/1 087）,CA was 94.6%（903/955）,very major error（VME） accounted for 0.3%（3/955）,major error（ME） accounted for 1.9%（18/955）,and minor error（MIE）accounted for 3.2%（31/955）. AST-N335 EA was 89.9%（1 388/1 544）,CA was 95.1%（1 414/1 487）,VME accounted for 0.3%（5/1 487）,ME accounted for 0.8%（12/1 487）,and MIE accounted for 3.8%（56/1 487）. AST-P639 EA was 95.4%（541/567）,CA was 98.7%（389/394）,ME accounted for 0.5%（2/394）,and MIE accounted for 0.8%（3/394）. Conclusions Vitek 2 Compact AST-N334,AST-N335,AST-P639 Chinese AST cards have high accuracy and reliability in clinical application. However,there are some error rates and limitations,which should be paid attention.

Key words: AST-N334, AST-N335, AST-P639, Chinese antimicrobial susceptibility card, Performance evaluation