Antibiotic Resistance Pattern and Prevalence of Aminoglycoside-Modifying Enzymes in Escherichia Coli and Klebsiella species Isolated from a Tertiary Care Hospital in Bangladesh.

This cross-sectional study was conducted in the Department of Microbiology of Dhaka Medical College, Dhaka, Bangladesh, from January 2015 to December 2015 to investigate the antibiotic resistance pattern and prevalence of genes encoding aminoglycoside-modifying enzymes in Escherichia coli and Klebsiella species isolated from a tertiary care hospital of Bangladesh. A total of 166 Escherichia coli, Klebsiella pneumoniae and Klebsiella oxytoca were isolated from urine, wound swab, pus, sputum and blood samples of patients of Dhaka Medical College Hospital. Antibiotic susceptibility test was performed by disk-diffusion technique. Genes encoding aminoglycoside-modifying enzymes [aac(3)-IIa, aac(6')-Ib, ant(2'')-Ia, aac(3)-Ia] among the isolated Escherichia coli and Klebsiella species were detected by polymerase chain reaction. The most prevalent aminoglycoside-modifying enzyme gene found was aac (3)-IIa (60.24%), followed by aac(6')-Ib (57.23%), ant(2'')-Ia (12.05%) and aac(3)-Ia (10.84%). Colistin and tigecycline were the most effective antibacterial agents against aminoglycoside-modifying enzymes followed by imipenem. The results of this study showed high proportion of aminoglycoside-modifying enzymes producing Escherichia coli and Klebsiella species in Bangladesh.