Evaluation of antibiotic resistant pattern, detection of exo genes, and determining biofilm formation ability among Pseudomonas aeruginosa isolated from blood and urine samples

Aim and Pseudomonas aeruginosa is an opportunistic pathogen playing role in various infections. Type three secretion system and biofilm formation capability are important virulence factors in this bacterium. In the present study, two virulence factors as well as antibiotic resistant patterns of isolates obtained from blood and urine samples were examined.
Material and After confirming 39 bacterial isolates as Pseudomonas aeruginosa, antibiogram was performed via disk diffusion method. Polymerase Chain Reaction was done in order to find the frequency of genes encoding effector proteins by type three secretion system.
18 and 21 Pseudomonas aeruginosa were isolated from blood and urine, respectively among which the most and the least resistance were observed against Cefpodoxime and Polymyxin B, respectively. ExoT gene was detected in 100% of both blood and urine samples and the frequency of other exo genes in blood samples was more than in urine samples. Isolates from urine samples were able to form strong biofilm, while isolates from blood samples could produce weak and moderate biofilms.
According to promotion of resistant Pseudomonas aeruginosa against antibiotics and their ability in developing infection, and the presence of isolates harboring toxin genes as well as capability of forming biofilm, the necessity of screening patients before antibiotic therapy is apparent, otherwise, the possibility of dissemination of different antibiotic resistant bacteria among population will be increased.