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

BMC Microbiol. 2020 Jan 8;20(1):7. doi: 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.

Keywords: Colistin-resistant; Gram-negative bacteria; Rapid ResaPolymyxin Acinetobacter/Pseudomonas NP test; Rapid diagnosis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acinetobacter baumannii / isolation & purification
  • Diagnostic Tests, Routine
  • Drug Resistance, Bacterial*
  • Gram-Negative Bacteria / isolation & purification*
  • Hospitals, Teaching
  • Klebsiella pneumoniae / isolation & purification
  • Microbial Sensitivity Tests
  • Oxazines / chemistry*
  • Polymyxins / pharmacology*
  • Pseudomonas aeruginosa / isolation & purification
  • Sensitivity and Specificity
  • Xanthenes / chemistry*

Substances

  • Oxazines
  • Polymyxins
  • Xanthenes
  • resazurin