Species identification and antibiotic susceptibilities of slime-forming and nonforming strains of coagulase negative staphylococci(CNS) isolated from clinically significant specimens were examined. Of 88 isolates, the greatest number of species
was
Staphylococcus epidermidis(61%), followed by S. haemolyticus(21%), S. hominis(6%), S. capitis(5%), simulans and S. auricularis(each 3%), and S. sciuri(1%). Percentages of slime-forming strains by species were 67% for S. auricularis, 52% for S.
epidermidis, 50% for S. capitis, 40% for S. hominis, and 17% for S. haemolyticus. Slime-forming rate of strains isolated from different lesions and specimens was highest with sputa(100%), followed bt ears(75%), bloods(60%), and eyes(57%). Mean
percentages of susceptibility to vancomycin/teicoplanin of slime-forming (41 strains) and -non-forming strains(47 strains) were as high as 100%/93% and 100%/98%, respectively, but were significantly lower to other antibiotics, penicillin(7%/6%),
gentamicin (27%/38%) oxacillin (27%/45%), erythromycin (39%/57%), trimethoprim-sulfamethoxazole (54%/60%), ciprofloxacin(56%/72%) and clindamycin (56%/74%). The weighted means of susceptibility of slime-forming and -nonforming strains to 9
antibiotics
were 42.2% and 62.6%, respectively. The multiresistant rates were much higher with slime-forming strains than with -nonforming stains.
These results suggested that the ability to form adherent biofilms or slime on the surface of polymers with CNS might be attributed to the antibiotic resistance rather than to the virulence.
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