Frequency of [aac(6’)-ie-aph(2”)] gene and aminoglycosids drug resistance in clinical staphylococcus aureus isolates by two phenotype and molecular methods

Mohammad reza Mohammadi,1,*



Staphylococcus aureus is one of the most common bacterial infection, these bacteria are an agent of nosocomial and community-acquired infections. aminoglycosides are potent bactericidal agents that often used in combination with either a β -lactam or a glycopeptide, especially in the treatment of staphylococcal. the aim of present study was to determine the frequency of [aac(6’)-ie-aph(2”)] gene encoding for enzymes of modify aminoglycosides by molecular method in clinical s. aureus isolates.


In this study, within 12 months, 115 clinical s. aureus isolates were collected from patients in karaj educational hospitals. all isolates were initially identified using standard biochemical and laboratory setting. antibiotic susceptibility pattern determined by disk diffusion method according to the clsi guideline. also the minimum inhibitory concentration (mic) was determined by the agar dilution method using gentamicin antibiotic powder. for detection of resistance gene were used from one pairs of specific primer and their abundance were determined by using pcr.


The highest rates of resistance to aminoglycosides were in kanamycin (47/8 %), gentamicin (46/9 %), tobramycin (46/9%),respectively and high-level non aminoglycoside- resistant antibiotics used in this study were doxycycline (50/4 %), ciprofloxacin (49/5 %), respectively. the frequency of [aac(6’)-ie-aph(2”)] gene in the isolates was determined by pcr method that 39.1 % reported.


Considering the increasing prevalence of resistance to aminoglycoside antibiotics in parallel with the excessive and indiscriminate clinical use of these drugs seems early detection and timely of resistant strains are essential, in order to select appropriate treatment options and prevent spread of resistance.


Staphylococcus aureus, [aac(6’)-ie-aph(2”)], pcr