Prevalence of aminoglycoside resistance genes in Pseudomonas aeruginosa isolated from a tertiary care hospital in Makkah, KSA

Atif H Asghar & Omar B Ahmed*

Aminoglycosides are the most frequently prescribed antimicrobial agents in Saudi Arabia; they are routinely used for the treatment of gram-negative bacillary infections. The aim of this study was to detect the resistance patterns against different aminoglycoside antibiotics and the prevalence of the genes encoding for resistance in Pseudomonas aeruginosa isolates from Hera General Hospital, Makkah, KSA. All isolates that were resistant to one or more aminoglycoside antibiotic were subjected to antibiotic susceptibility test and PCR analysis to detect the presence of the resistance genes: aac (6’)-Ib, aac(3)-Ia, aac(3)-II , ant(2’’)-Ia, rmtB, rmtC, armA, rmtA, rmtD, rmtE, and npmA. The results showed that 46.1% of the isolates were resistant to one or more aminoglycoside antibiotics, but only 43.3% of these aminoglycoside-resistant isolates harbored resistance genes. In addition, 43% of the isolates were resistant to ciprofloxacin, amikacin, and ceftazidime. The resistance genes most frequently observed in these isolates were rmtB (7.6%) followed by aac (6’)-Ib (6.1%), rmtC (4.6%), and armA (1.5%). Taken together, these results indicate that the aminoglycoside-resistance genes are highly prevalent and could easily spread among P. aeruginosa strains. Coordinated efforts and further research works are needed to control antibiotic resistance to aminoglycosides before to be a threatening crisis.