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[Sensitivity of 858 strains of staphylococci to 27 antibiotics]
Abstract:
Susceptibility to 27 antimicrobial agents of 858 strains of staphylococci was determined. Tested strains belonged to the following species: S. epidermidis, S. saprophyticus, S. haemolyticus, S. hominis, S. simulans, S. warneri, S. cohnii, S. xylosus and S. intermedius. The antibiotics were: penicillin G, amoxycillin, augmentin, oxacillin, streptomycin, kanamycin, tobramycin, dibekacin, amikacin, gentamicin, sisomycin, netilmicin, doxycycline, minocycline, chloramphenicol, erythromycin, josamycin, clindamycin, pristinamycin, rifampin, fusidic acid, fosfomycin, trimethoprim, sulfamethoxazole, cotrimoxazole, and vancomycin. The ATB system was used, with the criteria for categorization recommended by the Antibiotic Sensitivity Testing Committee. Penicillin-resistance, that was found in all species, was high for hospital-acquired strains (67 to 75%) but also for some other strains (32% for S. simulans). Oxacillin-resistance varied across species (0% for the least prevalent hospital strains, 6% for S. epidermidis and 28% for S. haemolyticus). All strains were susceptible to vancomycin. For some drugs, resistance was a characteristic of the species: resistance to fosfomycin was often found for S. saprophyticus, S. haemolyticus, S. warneri, S. cohnii, and S. capitis; resistance to trimethoprim was common for S. simulans, and S. haemolyticus. S. haemolyticus was the most resistant species, a fact that justifies routine identification of this pathogen in clinical specimens.
Insights
This study analyzed antimicrobial susceptibility in 858 staphylococci strains against 27 agents. Vancomycin showed universal susceptibility, while penicillin and oxacillin resistance varied significantly among species, with S. haemolyticus being the most resistant.
Area of Science:
- Microbiology
- Infectious Diseases
- Antimicrobial Resistance
Background:
- Staphylococci are significant human pathogens.
- Understanding their antimicrobial susceptibility is crucial for effective treatment.
- Species-specific resistance patterns can inform clinical decisions.
Purpose of the Study:
- To determine the antimicrobial susceptibility profiles of various staphylococci species.
- To identify specific resistance patterns within different staphylococci species.
- To highlight the clinical significance of S. haemolyticus resistance.
Main Methods:
- Antimicrobial susceptibility testing of 858 staphylococci strains against 27 antimicrobial agents.
- Inclusion of species: S. epidermidis, S. saprophyticus, S. haemolyticus, S. hominis, S. simulans, S. warneri, S. cohnii, S. xylosus, and S. intermedius.
- Utilized the ATB system and followed established antibiotic sensitivity testing criteria.
Main Results:
- All staphylococci strains demonstrated susceptibility to vancomycin.
- High penicillin resistance was observed in hospital-acquired strains (67-75%) and S. simulans (32%).
- Oxacillin resistance varied by species, notably 28% in S. haemolyticus.
- Species-specific resistance to fosfomycin and trimethoprim was noted.
- S. haemolyticus exhibited the highest overall resistance.
Conclusions:
- Vancomycin remains a reliable treatment option against tested staphylococci.
- Penicillin and oxacillin resistance are prevalent and vary significantly among staphylococci species.
- S. haemolyticus is a highly resistant species, necessitating its accurate identification in clinical settings.