DISTRIBUTION OF blaTEM GENE IN ESCHERICHIA COLI ISOLATED FROM HOSPITAL ENVIRONMENT

Abstract

Extended-spectrum β-lactamase (ESBL)-producing Escherichia coli may represent hospital reservoirs for antimicrobial-resistant bacteria. Houseflies (Musca domestica) can help spread these organisms from contaminated locations to areas where patients and health care workers might be. In the present study, blaTEM gene was determined in the E. coli collected from houseflies present in the environment of a tertiary care hospital in Lahore, Pakistan, and was their antimicrobial susceptibility profile described. 200 houseflies were collected from the patient wards, Hospital Corridor, Surgical wards, Waste Disposal Areas and surrounding areas. A total of 50 E. coli strains were successfully isolated and tested for antimicrobial susceptibility using the disk diffusion method as per Clinical and Laboratory Standards Institute (CLSI) guidelines. Genomic DNA was extracted by heat lysis and molecular identification of blaTEM was done by polymerase chain reaction. Of the 50 E. coli isolates, 23 (46%) were positive for blaTEM and 27 (54%) negative. There was significant variation in the antimicrobial susceptibility of the isolates. Sulfamethoxazole (42%) and colistin (42%) had the next highest resistance rates, with ceftazidime (100%) having the highest resistance rate. Fosfomycin, levofloxacin, tigecycline, amikacin and meropenem resistance rates were 12%, 10%, 10%, 8% and 0%, respectively. The results indicate that a significant portion of the E. coli   that was recovered from hospital houseflies possessed blaTEM and that the different isolates exhibited different resistance profiles. The above observations reinforce the need for environmental monitoring, good dissemination controls, infection controls, sanitation and drug utilization in hospitals and other healthcare facilities. Retracing the transmission of antimicrobial resistance in Pakistan must be further explored by larger scale multicenter studies, along with the molecular research of further resistance determinants.