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Published on: January 22, 2021
In vitro study of staphylococci susceptibility to gatifloxacin
Cristina Tuchiluş1, Antonia Poiată, D Buiuc
1School of Pharmacy, Microbiology Department, "Gr.T. Popa" University of Medicine and Pharmacy Iaşi.
Unlabelled:
Gatifloxacin is in a class of drug called fluoroquinolone antibiotics. It eliminates bacteria that cause many infections, such as pneumonia and bronchitis, sinus, respiratory tract and urinary tract infections and sexually transmitted diseases. Gatifloxacin ophthalmic solution is used to treat bacterial conjunctivitis.
Aim:
The purpose of this study was to evaluate the in vitro activity of gatifloxacin against recent 457 staphylococci, community isolates and compared it with that of pefloxacin.
Material And Method:
Powders of gatifloxacin and pefloxacin, obtained from commercial sources were tested in concentration range from 0.125 to 64 mg/l. Minimum inhibitory concentrations (MICs) were determined by the agar dilution method established by NCCLS guidelines.
Results:
The MIC 50 values for tested quinolones against coagulase-positive staphylococci are identically with MIC 90 (0.125 mg/l for gatifloxacin and 0.25 mg/l for pefloxacin respectively). Against coagulase-negative staphylococci the MICs 50 values were two-fold smaller than MICs 90 values for both gatifloxacin and pefloxacin.
Conclusions:
Gatifloxacin was more active than pefloxacin against coagulase-positive and coagulase-negative staphylococci.
