Mohammad Ali Zare - Departement of Microbiology, School of Medicine, Shahid Beheshti University of Medical Science
Aghil Bahramian - Departement of Microbiology, School of Medicine, Shahid Beheshti University of Medical Science
Mona Ghazi - Departement of Microbiology, School of Medicine, Shahid Beheshti University of Medical Science

BACKGROUND AND OBJECTIVESPseudomonas aeruginosa is one of the main cause of infections associated with the intensive care unit (ICU). Several virulence factors are implicated in Pseudomonas aeruginosa colonization and invasion, making Pseudomonas aeruginosa infection's outcome worse.Type III secretion system (T۳SS) effector proteins are among these virulence factors the purpose of this study, Molecular evaluation of type III secretory toxins in isolated MDR Pseudomonas aeruginosa from patients with burns and cystic fibrosis in Tehran hospitals .MATERIALS AND METHODSThis cross-sectional study was conducted on ۱۱۵ Pseudomonas aeruginosa bacteria samples from burn and cystic fibrosis patients. All presumptive isolates were identified by standard microbiologic tests. Antimicrobial susceptibility test was carried out by disk diffusion method. The presence of virulence genes was determined by PCR method.RESULTS AND DISCUSSIONIn this study, ۴۷ (۴۰.۹%) female samples and ۶۸ (۵۸.۳%) male samples were isolated. ۳۹ samples were from cystic fibrosis patients and ۷۶ samples were from burn patients. The highest drug sensitivity was reported for the antibiotics colistin (۹۸.۳%) and ceftazidime, avibactam (۹۱.۳%), and the highest drug resistance was reported for the antibiotics gentamicin (۹۲.۲%) and meropenem (۸۹.۶%). The prevalence of genes exoS (۹۳%), exoT (۱۰۰%), exo U (۸۲.۶%) was.CONCLUSION Overall, the association of MDR and the presence of the specific virulence genes can be a predictive marker for the persistence of these isolates in the hospitals and subsequently a worse clinical condition for the affected patients.

Pseudomonas aeruginosa, Antimicrobial resistance, type III secretion system