Activity of daptomycin against coryneform bacteria isolated from clinical samples

Abstract number: 1733_326

Salas C., Calvo J., Martínez-Martínez L.

Objectives: To evaluate the activity of Daptomycin (DAP) and six other agents against coryneform bacteria of clinical origin.

Methods: We evaluated 179 clinical isolates (1 per patient) including Corynebacterium striatum [Cstr (58)], C. amycolatum [Camy (25)], C. jeikeium [Cjei (25)], C. pseudodiphtheriticum [Cpse (21)], Listeria monocytogenes [Lmon (24)] and Arcanobacterium haemolyticum [Ahae (26)]. A microdilution assay, according to CLSI guidelines (M45-P), was used. The following antimicrobials were included: Clindamycin (CLI), Vancomycin (VAN), Teicoplanin (TEC), Linezolid (LNZ) and Quinupristin-dalfopristin (QDA). For DAP, Mueller-Hinton broth with 3% laked horse blood was supplemented with 50 mg/L of Ca++. S. pneumoniae ATCC 49619, S. aureus ATCC 29213 and E. faecalis ATCC 29212 were used as reference control strains.

Results: MICs 50/90 (mg/L) values are presented in table 1.

Table 1 

Conclusions: Daptomycin has a good in vitro activity against C. striatum, C. amycolatum, C. jeikeium, C. pseudodiphtheriticum and A. haemolyticum, and presented reduced activity against L. monocytogenes. Teicoplanin, Vancomycin, Linezolid and Quinupristin-dalfopristin are also active against these organisms. Clindamycin was poorly active, in vitro, except against A. haemolyticum and L. monocytogenes.