Association Between Biofilm Formation Gene Bla exoU and Metallo and Extend Spectrum Beta-lactamase Production of Multidrug Resistance Pseudomonas aeruginosa in Clinical Samples.

BACKGROUND

The presence of biofilm formation exoU gene is a significant challenge to infection control management in hospitals and exposure by Pseudomonas aeruginosa may lead to further spread and development of antimicrobial resistance.

METHODS

Out of 227 samples, 40 clinical isolates of P. aeruginosa were collected from patients attending public hospitals (Rizgary, Teaching hospital, Laboratory center, Raparin, Nanakaly hospitals) in Erbil city, Iraq over a period during June 2018 to March 2019 and were fully characterized by standard bacteriological procedures and antimicrobial susceptibility test and ESBL has been carried out by Vitek 2 compact system and by Vitek 2 compact system. The identification has been verified by all isolates as P. aeruginosa by using 16S rDNA with product size (956pb).

RESULTS

A high rate of resistance was seen against Penicillin, Lincomycin, Piperacillin and Chloramphenicol and Rifampicin (100 %), whereas Imipenem (5%) was found to be the most effective antimicrobial drug. Of all P. aeruginosa isolates, 30 (75% %) were identified as MDR, approximately 9 (22.5%) isolates were resistant to 9 drugs in burn samples. Quantitative biofilm determination using the Congo red method revealed that 28 isolates (70%) produced biofilm, biofilm production was significantly higher among MDR P. aeruginosa isolates while coproduction of Extended Spectrum β-lactamase (ESBL) together with Metallo β-lactamase (MBL) ESBLs MBLs was recorded in 52.5% of the isolates. Altogether 40 isolates were processed for the analysis by PCR assays and showed that 26 (70%) of P. aeruginosa isolates harboured the exoU encoding gene with product size (204) pb was more commonly seen in isolates obtained from burn isolates. In addition, exo U gene was significantly associated with the higher MDR (80%), 8 isolates (76.9%) had exoU gene with ESBL and (65%) had MBL and the same for MDR (80.8%) in samples for burning.

CONCLUSION

Our results showed surveillance of P. aeruginosa resistance against antimicrobial and ESBL and MBL is fundamental to monitor trends in susceptibility patterns and appropriately guide clinicians in choosing empirical or directed therapy.