Pseudomonas aeruginosa (P. aeruginosa) is a main clinical opportunistic pathogen that causes of morbidity and mortality among burn patients. therefore this study aimed to detection of RND-type efflux pump genes among P. aeruginosa isolates in Najaf City, using PCR technique. The study involved 68 specimen's obtained from burn patients visited burns unit center  as well as some chief clinical laboratories in Najaf City period December 2021 to  March 2022. This study showed among 68 burn patients 47(69.11%) and 12 (17.64%) of positive bacterial growth returned to gram-negative and gram-positive bacteria respectively. In contrast, 9(13.23%) of specimens were no growth. In the same respect, the results according to total positive bacterial growth have shown that the rate of P. aeruginosa isolates was 32(54.23%) At same as following 12(20.33%) in men compared with 20(33.89%) in women. The molecular results of efflux pump genes in this study revealed that  31 (96.87%%) of  P. aeruginosa isolates were contained MexA and MexD genes, While 30(93.75%) of isolates were positive for MexB gene. Moreover, 25(78.12%) of isolates were harbored MexC and MexY genes, as well as 23(71.87%) of isolates were harbored MexX gene.

Burn patients are at risk of severe infections caused by pseudomonas aeruginosa due to their immunosuppressive conditions. A one mechanism of resistance in this pathogen by AmpC beta-lactamases, therefore this study included molecular screening AmpC family genes among isolates of P. aeruginosa. The present work was conducted in Al-Sadr Medical City, and burns unit center as well as some chief clinical laboratories in Al-Najaf City period December 2021 to March 2022.  An entirety of  68 patients were checked to recognize P. aeruginosa isolates.  Bacterial growth were 59 (86.76%), as following   12(17.64%), 47 (69.11%)  and 9 (13.23%) for gram-positive bacteria, gram-negative and non- growth respectively .Results recorded 32(54.23%) of P. aeruginosa isolates. At same respect, the percentage of P. aeruginosa isolates in women were 20(33.89%) compared with 12(20.33%) in male. Results showed 20(62.5%) of isolates were resistance to piperacillin-tazobactam, , with a MIC of 128 µg/ml, Also data in table (2) showed that 32(100%) resistance to cefazoline antibiotic at MIC of 64 µg/ml. Whereas, the bacterial isolates showed less resistance to ceftazidime and cefepime, as the resistance ratios reached 21(65.62%) and 19(59.37%) respectively.the results showed that 20(62.5%) were resistant to imipenem while 19(59.37) and 18(56.25) were resistance gentamycin and amikacin respectively.