Carbapenemase Production and Detection of Colistin-Resistant Genes in Clinical Isolates of Escherichia Coli from the Ho Teaching Hospital, Ghana

BACKGROUND: Effective and successful treatment of infectious diseases is a significant gain in clinical settings. However, resistance to antibiotics, especially the last-resort medicines, including carbapenems and colistin is on the rise. AIM: The aim of this study was to detect carbapenemase production and colistin-resistant genes in clinical isolates of Escherichia coli. Method. The study was a cross-sectional study carried out from July 2018 to June 2019. One hundred and thirty-five nonrepetitive E. coli isolates obtained from various clinical samples were screened for carbapenemase production using meropenem (10 μg) and imipenem (10 μg) disks. Screened-positive isolates were further subjected to a confirmatory test using modified carbapenem inhibition method (mCIM). Deoxyribonucleic acid (DNA) was extracted from all the isolates to detect colistin-resistant genes by polymerase chain reaction. Data were analyzed using GraphPad Prism version 8.00 for Windows and IBM SPSS version 26 (IMB Corp. New York, USA). RESULTS: Of the 135 isolates, 2 were screened positive for carbapenemase production but tested negative to mCIM. With the colistin-resistant genes, only mcr-1 and mcr-2_700bp were detected in 3 of the E. coli isolates, representing 2.2%. The mcr-1 was detected in a high vaginal swab sample of a female aged between 65 and 84 years. Mcr-2_700bp was also detected in urine and blood samples of the patients. CONCLUSION: The study investigated the presence of carbapenemase and colistin-resistant genes in E. coli organisms. The absence of carbapenemase in the isolates and the detection of colistin-genes call for strict infection prevention and control practices to prevent their introduction and spread to other bacterial species, respectively.