Prevalence of Aminoglycoside Resistance Genes among EsβL Producer P. <i>aeruginosa</i> in Burn Cases

Pseudomonas aeruginosa recurrently develops resistant towards aminoglycosides by gaining of aminoglycoside modifying enzyme (AME) genes. The study aimed to assess the antibiotic susceptibility profile of P. aeruginosa isolated from burn infections in hospitals in Baquba, AL Najaf and Karbala. Detection of genes that mediate the production of AMEs. 175 Burn swab (110 males and 65 females) were collected then cultured on MacConkey‘s and Blood agar for primary culture, and Cetrimide agar was used to isolate and purify the bacteria and incubated aerobically at 37°C for 24 hours. Then, Vitek 2 system to validate the results. Results revealed that 70 (40%) Pseudomonas aeruginosa isolates were recovered out of 175 samples, 45 (64%) of isolates were from males while only 25 (35%) were recovered from females and age groups 15–20, 21–25, 26–30, 31–35 and 36–40 years were 14.3%, 18.5%, 22.9%, 14.3%, and 30%, respectively. Results showed that 94.28% of isolates were resistance toward Kanamycin followed by Meropenem and Augmentin with 85% rate. Cefepime showed 63% resistant while 38% were Tobramycin resistant. Gentamicin resistance was 33% while netilmicin showed 28% resistance. Amikacin showed only 5% resistance with highly significant difference (X2 360.39 and P value < 0.0001). The results indicated that aph(3’)-Ib gene was present in all of the isolates (100%), aac(6’)-Ib (77.5%) and aph(3’)-IIa (72.5%) were also highly prevalent, ant(3") constituted 22.5%, whereas armA represented 17.5%, and only two isolates (5%) possess aac3-IV and rmtB. These findings demonstrate the relative contributions of aminoglycoside resistance determinants to P. aeruginosa susceptibilities in burn units.