TABLE 1.

Phenotypic findings of S. pneumoniae strains with reduced susceptibilities to linezolid

Strain (yr of isolation, state)	Serotype	L4 phenotype	MIC (μg/ml)a								Reference or source
			LZD	VAN	PEN	AMO	ERY	CHL	CLI	TET
0566-02 (2001, GA)	19A	S20N	0.25	0.25	0.06	0.06	0.12	≤2	0.12	≤2	This study
3084-03 (2002, GA)	19A	S20N	1	0.25	0.12	0.06	0.25	≤2	0.5	≤2	This study
7828-04 (2004, CT)	014	ΔW65R66b	4	0.5	2	2	2	8	0.12	≤2	This study
2008227074 (2007, NM)	09N	Q67R, R72G	4	0.25	≤0.03	≤0.03	1	>8	0.06	≤2	This study
TN33388 (2003, TN)	33F	ΔK68G69	4	0.25	≤0.03	≤0.03	1	8	0.25	≤2	22

^aLZD, linezolid; VAN, vancomycin; PEN, penicillin; AMO, amoxicillin; ERY, erythromycin; CHL, chloramphenicol; CLI, clindamycin; TET, tetracycline. Current CLSI breakpoints: LZD susceptible (S), ≤2 μg/ml; VAN S, ≤1 μg/ml; PEN S, ≤2 μg/ml, PEN resistance (R), ≥8 μg/ml; AMO S, ≤2 μg/ml, and AMO R, ≥8 μg/ml; ERY S, ≤0.25 μg/ml, and ERY R, ≥1 μg/ml; CHL S, ≤4 μg/ml, and CHL R, ≥8 μg/ml; CLI S, ≤0.25 μg/ml, and CLI R, ≥1 μg/ml; and TET S, ≤1 μg/ml, and TET R, ≥4 μg/ml (10).

^bΔ, Deletion.