Determination of antibiotic susceptibility in klebsiella pneumoniae isolates using rapid method

Klebsiella pneumoniae is an opportunistic pathogen that causes nosocomial infections in urinary tract, blood, respiratory organs and soft tissues, pneumonia and bacteremia, usually affect immunosuppressive and hospitalized patients. It is thought that this microorganism has become a worldwide threat due to the development of multidrug resistance and the high mortality rates of its infections. Standard methods used routinely to detect the resistance of bacteria to antibiotics give results in at least one day. It is thought that the development of new methods that can provide antibiotic sensitivity results in a short time will contribute to the early initiation of antibiotic therapy, reducing the unnecessary use of broad-spectrum antibiotics and, as a result, minimizing the risk of developing resistance in bacteria. Between June 2021 and August 2022, 139 K pneumoniae isolates from blood samples routinely sent to Ondokuz Mayıs University Medical Faculty Hospital Bacteriology Laboratory from various services were included in the study Microdilution and resazurin microplate methods were used in the study. The results of the standard microdilution method for gentamicin and meropenem of the isolates included in the study were compared with the results of the resazurin microplate method. Accordingly, the 6th hour results for gentamicin were Categorical Agreement 99.28%, Essential Agreement 92.08%, Major Error 0% and Very Major Error 1.53% detected. At the 7th hour, Categorical Agreement 99.28%, Essential Agreement 96.40%, Major Error 0% and Very Major Error 1.53% was detected. For meropenem, the 6th hour Categorical Agreement 97.12%, Essential Agreement 91.36%, Minor Error 2.87%, Major Error 0% and Very Major Error was 0% detected. At the 7th hour, Categorical Agreement 97.12%, Essential Agreement 92.08%, Minor Error 2.87%, Major Error 0% and Very Major Error 0% was detected. As a result, there was no significant difference in the sixth and seventh hour results of the resazurin microplate method. According to these results, the resazurin microplate method has the potential to allow minimum inhibitory concentration results of gentamicin and meropenem sensitivity in K. pneumoniae isolates at the end of the sixth hour without the use of an extra device.