Enterokoklarda Yüksek Düzeyli Aminoglikozid Direnci ve Penisilin Aminoglikozid Sinerjizminin Araştırılması

Abstract

SUMMARY Enterococci are frequent cause of a wide variety of infections in humans. These organisms most commonly cause urinary tract infection, endocarditis, bacteremia, intraabdominal and pelvic infections, soft tissue and wound infections, menengitis and neonatal sepsis. Enterococci are important causative agents of nasocomial infections and superinfections as they resist to hospital and enviromental conditions, a variety of antimicrobial drugs intrinsicly and they have ability to acquire new resistance mechanisms. In recent years, it has been increasingly observed acquired antimicrobial resistance, especially high level aminoglycoside resistance and becoming a great clinic problem. In this study we identified 111 enterococcal species from clinic materials and we attempted to study presence of ^-lactamase, determine the susceptibility rate of penicillin of these species. Organisms were screened for high level resistance to aminoglycoside antibiotics including gentamicin, streptomycin and amikacin and the relation between penicillin and aminoglycosides was also studied. We used 20 Strep API for species identification of enterococci and nitrocefin test for determining the 0 lactamase production. While penicillin susceptibility was determined by broth microdilution method, both broth microdilution and agar screening tests were used in determining high level aminoglycoside resistance (HLR) for gentamicin, streptomycin and amikacin. The relation between penicillin and aminoglycoside antibiotics was studied by modified checkerboard method. It was found that E. faecalis (67,5 %) was the predominant isolate at the genus and none of them was producing (^-lactamase. 52.3 % of isolates were resistant to penicillin. The rates of HLR to gentamicine, streptomycin and amikacin was found as 50.5%, 41.4% and 0.9 % respectively. Broth microdilution and agar screening tests exhibited full correlation in revealing HLR to aminoglycosides. Both tests can be applied in finding HLR to gentamicine and streptomycin. Amikacin should not be used for finding HLR. Penicillin should not be combined with gentamicin or amikacin if there is HLR to gentamicin. In the same way if there is HLR to streptomycin, penisilin should not be combined with streptomycin. If there is isolated HLR to gentamicin, combination of penicillin and streptomycin can be a choice of treatment or if there is isolated HLR to streptomycin, gentamicin can be used in combination therapy alternatively 46

SUMMARY Enterococci are frequent cause of a wide variety of infections in humans. These organisms most commonly cause urinary tract infection, endocarditis, bacteremia, intraabdominal and pelvic infections, soft tissue and wound infections, menengitis and neonatal sepsis. Enterococci are important causative agents of nasocomial infections and superinfections as they resist to hospital and enviromental conditions, a variety of antimicrobial drugs intrinsicly and they have ability to acquire new resistance mechanisms. In recent years, it has been increasingly observed acquired antimicrobial resistance, especially high level aminoglycoside resistance and becoming a great clinic problem. In this study we identified 111 enterococcal species from clinic materials and we attempted to study presence of ^-lactamase, determine the susceptibility rate of penicillin of these species. Organisms were screened for high level resistance to aminoglycoside antibiotics including gentamicin, streptomycin and amikacin and the relation between penicillin and aminoglycosides was also studied. We used 20 Strep API for species identification of enterococci and nitrocefin test for determining the 0 lactamase production. While penicillin susceptibility was determined by broth microdilution method, both broth microdilution and agar screening tests were used in determining high level aminoglycoside resistance (HLR) for gentamicin, streptomycin and amikacin. The relation between penicillin and aminoglycoside antibiotics was studied by modified checkerboard method. It was found that E. faecalis (67,5 %) was the predominant isolate at the genus and none of them was producing (^-lactamase. 52.3 % of isolates were resistant to penicillin. The rates of HLR to gentamicine, streptomycin and amikacin was found as 50.5%, 41.4% and 0.9 % respectively. Broth microdilution and agar screening tests exhibited full correlation in revealing HLR to aminoglycosides. Both tests can be applied in finding HLR to gentamicine and streptomycin. Amikacin should not be used for finding HLR. Penicillin should not be combined with gentamicin or amikacin if there is HLR to gentamicin. In the same way if there is HLR to streptomycin, penisilin should not be combined with streptomycin. If there is isolated HLR to gentamicin, combination of penicillin and streptomycin can be a choice of treatment or if there is isolated HLR to streptomycin, gentamicin can be used in combination therapy alternatively 46