Susceptibility of multidrug resistant pseudomonas aeruginosa to commonly used biocides and its association with Qac efflux pump genes

ABSTRACT

To assess the prevalence of qacE?1 and qacE genes and their correlation to antibiotic and biocides resistance in Pseudomonas aeruginosa isolated in Egypt. Susceptibility was assessed for 14 antibiotics in 136 Pseudomonas aeruginosa isolates using agar diffusion method. The minimum inhibitory concentration of 6 biocides, Savlon, Povidone-iodine, Phenol, Formalin and two Chlorine releasing agents were determined using macro-dilution method. Presence of qacE?1 and qacE genes was examined by polymerase chain reaction. There were 34.4 % of Pseudomonas aeruginosa isolates identified as multidrug resistant. Phenol and formalin displayed a higher antiseptic/disinfectant activity compared to other biocides tested. Savlon and Povidone-iodine displayed antibacterial activity when used in recommended dilutions. Minimum inhibitory concentration values of chlorine releasing agents were higher than the dilution prescribed by their manufactures. The qacE gene was only detected among multidrug resistant Pseudomonas aeruginosa. The qacE?1 gene was identified in 57.8% of multidrug resistant isolates and 21.4% in susceptible strains. The prevalence of qac genes among clinical Pseudomonas aeruginosa were 42.3%. Current study concluded thatthere was a correlation between multidrug resistance Pseudomonas aeruginosaandqacE?1 gene, whereas there was no correlation between increased MIC values of biocides and the presence of Qac genes