Aim: The emergence of multidrug-resistant (MDR) bacteria is the most dangerous threat for the treatment of infectious diseases. The aim of this study was to detect and characterize extended spectrum beta-lactamases (ESBLs) and carbapenemaseproducing Klebsiella pneumoniae and Escherichia coli among patients and environment of intensive care units (ICUs) of three tertiary care hospitals in Pakistan.
Materials and Methods: A total of 82 samples from ICU's patients and inanimate environment (injection trays, wash basins, door handles, hand swabs of professionals, and ICU fridges) were screened for ESBL by culturing on CHROMagar-ESBL. ESBL and carbapenemases production were confirmed by double disc synergy test and modified Hodge's test, respectively. Polymerase chain reaction was used to detect ESBL encoding genes bla cefotaxime (CTX-M), blaCTX-M-1, blaCTX-M-2, blaCTX-M-9, blaTEM, blaSHV and carbapenemase genes blaKPC, bla New Delhi metallo-beta-lactamase-1, blaOXA-48 and blaVIM.
Results: Overall, ESBL production was found high 30/82 (36.5%) among isolates of which 15.8% K. pneumoniae and 20.7% E. coli were identified. All the K. pneumoniae and majority of E. coli isolates were MDR, i.e., resistance to three or more antimicrobial categories. Molecular characterization showed the blaCTX-M-1 as the predominant genotype found in 17/21 (80%) of the isolates. None of the strains was found positive for carbapenemase-encoding genes.
Conclusion: In conclusion, this study demonstrates the emergence of MDR ESBL producing strains among ICU patients and hospital environment, posing a serious threat for the control of nosocomial infections.