PREVALENCE OF VIRULENCE GENES IN CLINICAL ISOLATES OF PSEUDOMONAS AND ITS ASSOCIATION WITH ANTIBIOTIC SUSCEPTIBILITY

Abstract

Pseudomonas aeruginosa is a gram negative rod shaped and opportunistic bacterium that causes Opportunistic infections with help of potential virulence factors in immunosuppressed patients. Exotoxin A and exoenzyme S, catalyze the transfer of ADP-ribose moiety of NAD to plasma proteins in eukaryotic host cells. Exotoxin A has major role in Pseudomonas aeruginosa that causes toxicity by inhibition of protein synthesis while Exo S is involved in invasion, colonization and dissemination of infections. The main objective of this study was to investigate the association between virulence genes of Pseudomonas (exotoxin A and exoenzyme S) with antibiotic resistance patterns. This research was done in Microbiology Laboratory of Shaikh Zayed Hospital, Lahore, during October to December, 2021. Total 11,187 clinical samples were processed at culture and sensitivity bench in this tenure and 100 isolates of Pseudomonas aeruginosa were isolated on basis of morphological characters and standard biochemical procedures in microbiology laboratory. Disk diffusion method (Kirby-Bauer) was used for testing   Antibiotic Susceptibility. The toxA and exoS genes were detected in 100 clinical isolates by PCR technique. The correlation was used for finding the association between detected genes and antibiotic susceptibility patterns of Pseudomonas aeruginosa. In antibiotic susceptibility pattern Gentamicin was most common resistant drug and Polymixin B and Colistin were most effective drugs with 100% sensitivity. Prevalence of toxA+ and exoS+ strains was 95% and 87%, respectively. Correlation was used to find association between genes and drug resistance pattern and there was no significant association P value <0.5. High frequency of toxA+ and exoS+ strains isolated from all type of clinical specimens suggest these genes are also possible cause of resistance of drugs but negative association between them highlights that there are some other factors other than these genes which need to be focused in future studies to come over drug resistivity of Pseudomonas  aeruginosa.