Daptomycin tested against 915 bloodstream isolates of viridans group streptococci (eight species) and Streptococcus bovis.
OBJECTIVE
To evaluate the activity of daptomycin tested against numerous species of viridans group streptococci and Streptococcus bovis, which are associated with wound infections, sepsis, cellulitis, endocarditis, abscesses and dental caries. The incidence of penicillin-resistant (non-susceptible) and MLS(B)-resistant strains among viridans group streptococci often varies by species.


METHODS
The activity of daptomycin was compared with seven other antimicrobial classes using reference broth microdilution and disc diffusion methods tested against 915 bacteraemic isolates of streptococci (815 viridans group strains; 100 S. bovis).


RESULTS
Among all species of viridans group streptococci and S. bovis, 99.9% of isolates were susceptible to daptomycin (MIC values, < or = 0.016-2 mg/L). In contrast, penicillin, erythromycin and tetracycline susceptibility varied widely between species. Erythromycin susceptibility was in the range 48.6-88.7%, penicillin susceptibility in the range 65.5-98.1% and tetracycline in the range 35.0-93.9%. The inter-method agreement between daptomycin and linezolid resistance (comparison agent) disc diffusion and broth microdilution test results was high, each showing near complete susceptibility (99.9%).


CONCLUSIONS
Daptomycin is an active antimicrobial agent that has a usable potency against eight species of viridans group streptococci, as well as S. bovis, with all MIC values at < or =2 mg/L.
Streit
Jennifer M
JM
The JONES Group/JMI Laboratories, North Liberty, IA 52317, USA.
Steenbergen
Judith N
JN
Thorne
Grace M
GM
Alder
Jeffrey
J
Jones
Ronald N
RN
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D017576:Daptomycin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D008826:Microbial Sensitivity Tests; D013291:Streptococcus / Q000187:drug effects*; D016985:Streptococcus bovis / Q000187:drug effects
D000900:Anti-Bacterial Agents; D017576:Daptomycin