Typing of fliC Gene in Pseudomonas aeruginosa Metallo-Beta- Lactamase Producer Strains Isolated from Clinical Specimens

Aims Carbapenem resistant Pseudomonas aeruginosa resulting from metallo-β-lactamases (MBLs) has been reported to be an important cause of nosocomial infection and is a serious therapeutic problem worldwide. The aim of the present study was to determine the fliC (flagellin) typing and their prevalence rate in P. aeruginosa producing MBL isolated from clinical specimens in Ahvaz, Iran. Materials & Methods In the present experimental study, isolates were related to the previous study collected from hospitalized patients in Golestan and Imam Khomeini, in Ahvaz, Iran, during 9 months in 2012. Strains were identified using microscopic and biochemical tests. Then, the susceptibility antibiotic tests were performed on all isolates. Imipenem (IMP) and IMP+EDTA (IMP/IMP+EDTA) combined disk phenotypic test was performed for detection of MBL producing strains that were resistant to IMP. Finally, PCR was performed to detect fliC genes in IMP resistant strains. Findings Out of 100 examined isolates, 47 isolates were resistant to IMP. Among 47 imipenem resistant strains, 41 strains were MBL producers. Eighty-three percent of the strains contained fliC gene that 48 isolates had type A and 32 isolates had type B. Conclusion Eighty-three percent of the specimens have flagellin (fliC) gene, which out of them, 48 strains of P. aeruginosa (60.0%) have type A flagellin and 32 strains (40.0%) have type B. Twenty-four of the 41 strains of MBL producer (60.0%) have type A and 16 strains (40.0%) have type B and only one strains lacks the flagellin gene, so the flagella plays a significant role in the bacterial virulence.