الفهرس 
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Abstract
P. aeruginosa is an opportunistic pathogen that normally inhabits humans and avian species; it becomes pathogenic under stress factors such as immunosuppression or the presence of other concomitant infections, causing severe clinical manifestations. P. aeruginosa isolates were screened for the presence of three selected virulence gene markers by PCR, and the results revealed that toxA, lasB, and exoS genes were successfully amplified from all P. aeruginosa isolates (100%) Positive P. aeruginosa strains were examined to determine the existence of virulence genes. The PCR assay revealed that toxA represented the most abundant toxin gene discovered amongst the tested strains (30/30; 100%), followed by the exoS gene (25/30; 83.3%) and the lasB gene (20/30; 66.6%) All isolates were completely resistant (100%) to penicillin, amoxicillin, ceftriaxone, ceftazidime, streptomycin, erythromycin, spectinomycin, and doxycycline followed by kanamycin (66.6%) and cefuroxime (56.6%) and they displayed an intermediate resistant to cefotaxime (90%), apramycin (50%), and amikacin (36.6%). While, P. aeruginosa isolates were more sensitive to meropenem (83.3%), imipenem (70%), colistin sulphate (66.66%), ciprofloxacin (53.3%), and gentamicin (46.6%). MDR was found in 100% of the isolates. The patterns P, AX, CRO, CAZ, S, E, SPT, DO, CXM, and K represented the most common antimicrobial resistance profile found in P. aeruginosa isolates.The higher MDR index (0.8) was noticed among 2 isolates that were resistant to 14 types of the 18 tested antimicrobial discs. The multidrug resistant index for MDR P. aeruginosa isolates ranged from 0.5 to 0.8. Out of 55 isolates tested for ESBL production by DDST, 12 (21.8%) isolates were confirmed as ESBL producers. Positive isolates showed enhancement in the zone of inhibition in one or two tested discs (ceftazidime-CAZ 30 μg, cefotaxime-CTX 30 μg) towards amoxicillin-clavulanic acid (D-shape or keyhole shape). While, PCDDT identify 15 (27.3%) ESBL producer isolates. The isolates exhibited a significant enhancement in the zone size with the combination disc amoxicillin-clavulanic acid (≥5 mm) when compared with ceftazidime discs alone. The PCDDT detected the same 12 strains of DDST as well as an additional 3 strains as ESBL producers. Genotypically, the distribution of blaTEM, blaSHV, blaCTX, and blaOXA-10 genes was detected in 40 (72.7%), 38 (69.1%), 30 (54%), and 9 (16.4%) isolates, respectively, while no isolate carried either blaVEB-1 or blaOXA-2 genes.