Molecular typing and antimicrobial sensitivity of MDR-Pseudomonas aeruginosa isolated from Coronavirus disease-2019 patients

Abstract

Abstract Background Pseudomonas aeruginosa is a common co-infecting pathogen recognized among COVID-19 patients, leading to worsening illness and a high mortality rate. We aimed to demonstrate molecular typing and antimicrobial sensitivity of MDR-Pseudomonas aeruginosa isolated from COVID-19 patients. Methods Between December 2020 and July 2021, 15 P. aeruginosa were isolated from COVID-19 patients in the ICU ward at Sina Hospital in Hamadan, west of Iran. The Antimicrobial resistance of the isolates were determined operating the disk diffusion (DDT) and minimum inhibitory concentration (MIC) tests. The double-disk synergy method, Modified Hodge test, and PCR were utilized to detect P. aeruginosa extended spectrum beta-lactamase (ESBLs) and carbapenemase producers. Microtitre plate assay was operated to evaluate the biofilm formation ability of the isolates. The isolates' phylogenetic relatedness was revealed using the multilocus variable-number tandem-repeat analysis (MLVA) method. Results The results showed P. aeruginosa isolates had the most elevated resistance to imipenem (93.33%), levofloxacin (93.33%), trimethoprim-sulfamethoxazole (93.33%), ceftriaxone (80%), ceftazidime (80%), gentamicin (60%), ciprofloxacin (60%), and cefepime (60%). In the broth microdilution method, 100%, 100%, 13.33%, and 20% of isolates showed resistance to imipenem, meropenem, colistin, and polymyxin B, respectively. Extended-spectrum beta-lactamases and carbapenemase enzymes were detected in 20% and 66.66% of the isolates, respectively. Biofilm formation was seen in 100% of isolates. On the basis of the PCR results, blaOXA−48, blaTEM, blaIMP, blaSPM, blaPER, blaVEB, blaNDM, blaSHV, and blaCTX−M were detected in 100%, 86.67%, 86.67%, 40%, 20%, 20%, 13.33%, 6.67%, and 6.67%, of the isolates, respectively. The MLVA typing technique showed 11 types and seven main clusters. Most isolates belonged to clusters VII, I, and V. Conclusions As to observe high genetic diversity among P. aeruginosa isolates from COVID-19 patients in the ICU, it is indispensable to regularly monitor the epidemiology and genetical relatedness of the isolates to trace any insignificant alteration in the epidemiology of P. aeruginosa isolates in the COVID-19 epidemic.