Abstract
Background. Klebsiella pneumoniae (KP) is one of the most important causes of hospital-acquired infection and one of the most important causes of ventilator-associated pneumonia. During the present study, we investigated the resistance to fluoroquinolones among KP isolates collected from patients referred to hospitals affiliated with Ardabil University of Medical Sciences in 2020.
Methods. In this descriptive, cross-sectional study, the minimum inhibitory concentration (MIC) of ciprofloxacin (CLX) was determined by the agar dilution method, and mutations in the gyrA and parC genes and the presence of resistance genes, such as accA, qnr, and qepA, were evaluated using the polymerase chain reaction method.
Results. Out of 100 isolates, 43% (n = 43) were resistant to CLX. The MIC range of CLX was 0.5 µg/mL to 1024 µg/mL. Isolates with a high MIC of CLX were investigated for mutations in the gyrA and parC genes. In the investigation of mutations in gyrA, a substitution from serine to isoleucine was observed at position 83, while no mutation was found in parC. In 10 isolates (10%), the presence of the aac (6')-Ib-cr gene was detected, while qepA and qnr resistance genes were not observed in any of the isolates.
Conclusion. Based on the findings, a high frequency of the aac (6')-Ib-cr gene was reported in this study. Since this gene is located on a plasmid, it can be easily transferred between KP strains in a hospital setting and leads to the spread of resistance to fluoroquinolones.
Practical Implications. The emergence of bacterial resistant strains is on the rise and has become a serious public health problem worldwide. Infection with these strains leads to complicated diseases with worse outcomes, prolonged hospitalization, increased healthcare costs, an increased need to use second-line drugs with costs, and treatment failures.