Investigation of antimicrobial resistance patterns and molecular typing of Pseudomonas aeruginosa isolates among Coronavirus disease-19 patients

BACKGROUND

Pseudomonas aeruginosa is a common co-infecting pathogen recognized among COVID-19 patients. We aimed to investigate the antimicrobial resistance patterns and molecular typing of Pseudomonas aeruginosa isolates among Coronavirus disease-19 patients.

METHODS

Between December 2020 and July 2021, 15 Pseudomonas aeruginosa were isolated from COVID-19 patients in the intensive care unit at Sina Hospital in Hamadan, west of Iran. The antimicrobial resistance of the isolates was determined by disk diffusion and broth microdilution methods. The double-disk synergy method, Modified Hodge test, and polymerase chain reaction were utilized to detect Pseudomonas aeruginosa extended spectrum beta-lactamase and carbapenemase producers. Microtiter plate assay was performed to evaluate the biofilm formation ability of the isolates. The isolates phylogenetic relatedness was revealed using the multilocus variable-number tandem-repeat analysis method.

RESULTS

The results showed Pseudomonas aeruginosa isolates had the most elevated resistance to imipenem (93.3%), trimethoprim-sulfamethoxazole (93.3%), ceftriaxone (80%), ceftazidime (80%), gentamicin (60%), levofloxacin (60%), ciprofloxacin (60%), and cefepime (60%). In the broth microdilution method, 100%, 100%, 20%, and 13.3% of isolates showed resistance to imipenem, meropenem, polymyxin B, and colistin, respectively. Ten (66.6%) isolates were identified as multiple drug resistance. Carbapenemase enzymes and extended spectrum beta-lactamases were identified in 66.6% and 20% of the isolates, respectively and the biofilm formation was detected in 100% of the isolates. The blaOXA-48, blaTEM, blaIMP, blaSPM, blaPER, blaVEB, blaNDM, blaSHV, and blaCTX-M genes were detected in 100%, 86.6%, 86.6%, 40%, 20%, 20%, 13.3%, 6.6%, and 6.6% of the isolates, respectively. The blaVIM, blaGIM, blaGES, and blaMCR-1 genes were not identified in any of the isolates. The MLVA typing technique showed 11 types and seven main clusters and most isolates belong to cluster I, V and VII.

CONCLUSION

Due to the high rate of antimicrobial resistance, as well as the genetic diversity of Pseudomonas aeruginosa isolates from COVID-19 patients, it is indispensable to monitor the antimicrobial resistance pattern and epidemiology of the isolates on a regular basis.

Potential of Bacillus subtilis Against SARS-CoV-2 - A Sustainable Drug Development Perspective

The COVID-19 pandemic had anomalous yet inevitable impacts on the world's economies, healthcare systems, and all other aspects of life. Researchers began to uncover hidden routes to find a new horizon of hope using underrated resources. Biosurfactants are sustainable biomolecules with an active surface, unique characteristics, and extensive uses. Bacillus species showed the highest amount of biosurfactant activities and Bacillus subtilis is one of them. The antiviral, antimicrobial, and anti-inflammatory activity of B. subtilis was proven recently. The great advantage is its non-toxic nature. Pro-inflammatory cytokines including IL-1 β, 6, 8, 12, 18, and TNF-(α are secreted in higher amounts when neutrophils and monocytes are triggered by biosurfactant bacteria. This point of view furnishes the potential application of B. subtilis and its biomolecules against COVID-19, either in the form of a vaccine/therapeutic agent, for a greener environment, healthier life, and environmental sustainability. Further in vivo and clinical trials are needed to validate this hypothesis.

Molecular Detection of blaOXA-type Carbapenemase Genes and Antimicrobial Resistance Patterns among Clinical Isolates of Acinetobacter baumannii

Acinetobacter baumannii is a bacterium found in most places, especially in clinics and hospitals, and an important agent of nosocomial infections. The presence of class D enzymes such as OXA-type carbapenemases in A. baumannii is proven to have a key function in resistance to carbapenem. The aim of the current study is to determine the blaOXA _-type carbapenemase genes and antimicrobial resistance among clinically isolated samples of A. baumannii. We assessed 100 clinically isolated specimens of A. baumannii from patients in intensive care units of educational hospitals of Hamadan, West of Iran. The A. baumannii isolates' susceptibility to antibiotics was performed employing disk diffusion method. Multiplex polymerase chain reaction was used to identify the bla _OXA-24-like , bla _OXA-23-like , bla _OXA-58-like , and bla _OXA-51-like genes. The bla _OXA-23-like , bla _OXA-24-like, and bla _OXA-58-like genes' prevalence were found to be 84, 58, and 3%, respectively. The highest coexistence of the genes was for bla _OXA-51/23 (84%) followed by bla _{OXA-51/24-like} (58%). The bla _{OXA-51/23-like} pattern of genes is a sort of dominant gene in resistance in A. baumannii from Hamadan hospitals. The highest resistance to piperacillin (83%) and ciprofloxacin (81%) has been observed in positive isolates of bla _OXA-23-like . The A. baumannii isolates with bla _OXA-58-like genes did not show much resistance to antibiotics. Based on the results of the phylogenetic tree analysis, all isolates have shown a high degree of similarity. This study showed the high frequency of OXA -type carbapenemase genes among A. baumannii isolates from Hamadan hospitals, Iran. Thus, applying an appropriate strategy to limit the spreading of these strains and also performing new treatment regimens are necessary.