OXA-48 Carbapenemase-Encoding Transferable Plasmids of Klebsiella pneumoniae Recovered from Egyptian Patients Suffering from Complicated Urinary Tract Infections.

Abstract

Simple SummaryGram-negative bacteria are common causes of urinary tract infections (UTIs), some of which can resist treatment by antibiotics, including carbapenems, which are last resort treatment options. This study aimed to report the resistance of some Gram-negative bacteria causing complicated UTIs to carbapenems at two important hospitals in Cairo, Egypt, and to determine the possible transfer of this resistance to other bacterial species. The collected bacteria were tested for antibiotic resistance and detection of the genes responsible for this resistance. A total of 256 Gram-negative bacterial clinical isolates were collected, 65 (25.4%) of which showed carbapenem resistance. The detected carbapenem resistance genes were blaOXA-48, blaVIM, blaKPC, and blaNDM genes. The blaOXA-48, among other genes, was successfully transferred to a previously susceptible bacteria, making it resistant. The study concluded that the rate of carbapenem resistance among Gram-negative bacteria causing UTIs in Cairo, Egypt is relatively high and can be transferred among bacterial hosts.Gram-negative bacteria are common causes of urinary tract infections (UTIs). Such pathogens can acquire genes encoding multiple mechanisms of antimicrobial resistance, including carbapenem resistance. The aim of this study was to detect the carbapenemase-producing ability of some Gram-negative bacterial isolates from urine specimens of patients suffering from complicated UTIs at two vital tertiary care hospitals in Cairo, Egypt; to determine the prevalence of carbapenemase genes among plasmid-bearing isolates; and explore the possibility of horizontal gene transfer to other bacterial species. The collected isolates were subjected to antimicrobial susceptibility testing, phenotypic analysis of carbapenemase production, and molecular detection of plasmid-borne carbapenemase genes, then the extracted plasmids were transformed into competent E. coli DH5α. A total of 256 Gram-negative bacterial clinical isolates were collected, 65 (25.4%) isolates showed carbapenem resistance of which 36 (55.4%) were carbapenemase-producers, and of these 31 (47.7%) harbored plasmids. The extracted plasmids were used as templates for PCR amplification of blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP carbapenemase genes. The blaOXA-48 gene was detected in 24 (77.4%) of the tested isolates while blaVIM gene was detected in 8 (25.8%), both blaKPC and blaNDM genes were co-present in 1 (3.2%) isolate. Plasmids carrying the blaOXA-48 gene from 4 K. pneumoniae clinical isolates were successfully transformed into competent E. coli DH5α. The transformants were carbapenemase-producers and acquired resistance to some of the tested antimicrobial agents as compared to untransformed E. coli DH5α. The study concluded that the rate of carbapenem resistance among Gram-negative bacterial uropathogens in Cairo, Egypt is relatively high and can be transferred horizontally to other bacterial host(s).