Evaluation of resazurin-based assay for rapid detection of polymyxin-resistant gram-negative bacteria

• Main Authors: Huaiyu Jia, Renchi Fang, Jie Lin, Xuebin Tian, Yajie Zhao, Lijiang Chen, Jianming Cao, Tieli Zhou
• Format: Article
• Language: English
• Published: BMC 2020-01-01
• Series: BMC Microbiology
• Subjects: Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test; Colistin-resistant; Gram-negative bacteria; Rapid diagnosis
• Online Access: https://doi.org/10.1186/s12866-019-1692-3

Abstract Background Colistin resistance is considered a serious problem due to a lack of alternative antibiotics. The Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test is a resazurin reduction-based technique that relies on the visual detection of bacterial growth in the presence of a defined concentration of colistin. The aim of this study was to evaluate the performance of the Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test in the detection of colistin susceptibility in common clinical Gram-negative bacteria. Results A total of 253 clinical isolates from a teaching hospital, including Acinetobacter baumanii (n = 58, 8 colistin-resistant), Pseudomonas aeruginosa (n = 61, 11 colistin-resistant), Klebsiella pneumoniae (n = 70, 20 colistin-resistant) and Escherichia coli (n = 64, 14 colistin-resistant) were tested in this study. The sensitivity and specificity of the Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test compared to Broth microdilution method was 100 and 99%, respectively. Conclusions Our results suggest that Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test could be used as an accurate detection method for colistin resistance.