Table 2: Minimal Inhibitory Concentrations of 10 Antimicrobial Agents Against Actinomyces species. (n=34), Including Type Strains of 16 Different Species

Antimicrobial Agent MIC (mg/L) ** MIC Range (mg/L)
0.004 0.008 0.016 0.032 0.064 0.125 0.25 0.5 1 2 8 16 32
Benzylpenicillin# 2* 1 1 9 6 6 4 5 0,004-0,5
Piperacillin/tazobactam# 1 1 2 2 7 7 4 7 3 <0,016-2
Ceftriaxone 1 1 2 6 8 5 6 4 0,016-32
Meropenem 5 5 4 8 5 2 1 4 0,012-32
Erythromycin# 21 8 1 4 <0,016-0,094
Clindamycin# 4 13 3 5 4 1 1 3 0,016-1,5
Linezolid 2 9 18 1 4 0,125-0,75
Moxifloxacin 1 3 8 10 6 4 1 1 0,064-32
Tetracycline# 1 11 11 5 1 1 4 0,094-16
Tigecycline 1 10 12 8 3 0,016-0,125

1)* Number of strains with adequate growth for reading MIC
2)** Number of strains with undefined MIC due to poor growth.
3) Grey shadings mark the upper limit for sensitivity according to international guidelines. Values above indicates resistance. (Pharmacological breakpoints 2007 from SRGA are used for antibiotics marked.
# Pk/pd breakpoints from EUCAST are used for the other antibiotics).