| Title | Rapid determination of carbapenem resistance by low-cost colorimetric methods: Propidium Iodide and alamar blue staining |
|---|---|
| Author | Jiyoon Choi1†, Jiwon Baek1†, Daehyuk Kweon2, Kwan Soo Ko3,4, and Hyunjin Yoon1,5* |
| Address | 1Department of Molecular Science and Technology, Ajou University, Suwon 16499, Republic of Korea, 2Department of Genetic Engineering and Center for Human Interface Nano Technology, Sungkyunkwan University, Suwon 16419, Republic of Korea, 3Department of Molecular Cell Biology, Sungkyunkwan University, School of Medicine, Suwon 16419, Republic of Korea, 4Asia-Pacific Research Foundation for Infectious Diseases, Seoul 06367, Republic of Korea, 5Department of Applied Chemistry and Biological Engineering, Ajou University, Suwon 16499, Republic of Korea |
| Bibliography | Journal of Microbiology, 58(5),415-421, 2020, |
| DOI | 10.1007/s12275-020-9549-x |
| Key Words | carbapenem, resistance, propidium iodide, alamar blue, Gram-negative pathogen |
| Abstract | Carbapenems are a class of β-lactam antibiotics with a broad antimicrobial activity spectrum. Owing to their sturdy structures resistant to most β-lactamases, they have been regarded as one of the last-resort antibiotics for combating multidrugresistant bacterial infections. However, the emergence of carbapenem resistance increases predominantly in nosocomial pathogens. To prevent spread of carbapenem resistance in early stages, it is imperative to develop rapid diagnostic tests that will substantially reduce the time and cost in determining carbapenem resistance. Thus, we devised a staining-based diagnostic method applicable to three different Gram-negative pathogens of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae, all with the high potential to develop carbapenem resistance. Regardless of the resistance mechanisms presented by bacterial species and strains, double staining with propidium iodide (PI) and alamar blue (AB) identified resistant bacteria with an average sensitivity of 95.35%, 7 h after imipenem treatments in 343 clinical isolates. Among the three species tested, A. baumannii showed the highest diagnostic sensitivity of 98.46%. The PI and ABmediated staining method could be a promising diagnostic method with high-throughput efficacy and low cost. |