Detection of plasmid-mediated colistin resistance in carbapenem-resistant Escherichia coli and Klebsiella pneumoniae isolates in Suez Canal University Hospitals

Khattab, Sally; Al Sweify, Mohamed Ali; Metwally, Lobna; Elazab, Sahar; Hashem, Asmaa

doi:10.21608/mid.2021.78200.1162

Detection of plasmid-mediated colistin resistance in carbapenem-resistant Escherichia coli and Klebsiella pneumoniae isolates in Suez Canal University Hospitals

Document Type : Original Article

Authors

¹ Department of Medical Microbiology and Immunology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt.

² Department of Medical Microbiology and Immunology, Faculty of Medicine, Suez Canal University, Ismailia, Egypt. Microbiology department, College of Medicine, Taif university

10.21608/mid.2021.78200.1162

Abstract

Background: The polymyxins including colistin are the “last resort” antibiotics for treatment of infections with carbapenem resistant Enterobacteriaceae. Recently, transferable colistin resistance mediated by the mcr-genes has been described in Enterobacteriaceae. The Testing of colistin susceptibility is challenging. The aim of the work is to detect the occurence of mcr-1 and mcr-2 genes in phenotypically colistin-resistant carbapenem resistant Escherichia coli and Klebsiella pneumoniae isolates using conventional PCR. Methods: One hundred and sixteen carbapenem-resistant E.coli and K.pneumoniae isolates were collected from patients admitted to different wards of Suez Canal University Hospitals in Ismailia. Urine, endotracheal aspirates, blood, pus and sputum specimens were collected from different patients. Minimal inhibitory concentration by broth microdiluton method was done to assess phenotypic colistin resistance. The colistin resistant E.coli and K.pneumoniae isolates were tested by conventional PCR to detect plasmid mediated mcr-1 and mcr-2 genes. Chi-square test was applied and p < /em>-value < 0.05 was considered statistically significant. Results: Forty three isolates out of 116 carbapenem resistant isolates (37.1%) were colistin resistant as shown by MIC by broth microdiluton method. The 43 colistin resistant E.coli and K.pneumoniae isolates were tested by conventional PCR to detect plasmid mediated mcr-1 and mcr-2 genes. Two mcr-2 genes and one mcr-1 gene were detected. Conclusion: Results revealed that the prevalence of colistin resistance among carbapenem-resistant E.coli and K.pneumoniae in SCUHs is concerning; further limiting potential therapeutic options. Plasmid mediated colistin resistance genes mcr-1 and mcr-2 is emerging in SCUHs which refer to a problem in the hospital as by horizontal transfer of this plasmid, the resistance can spread to many isolates in the hospital.