Table 1.

Comparison of vancomycin and teicoplanin MICs and disk diffusion zone sizes with the interpretive results for isolates of staphylococci exhibiting decreased susceptibility to glycopeptides

Isolate (source)VancomycinTeicoplanin
MICaDDbMIC DD
S. aureus Mu50 (Japan)8 (I)17 (S)8 (S)15 (S)
S. aureus Mu3 (Japan)2 (S)19 (S)16 (I)14 (S)
S. aureusMu3-8R (Japan)8 (I)17 (S)32 (R)13 (I)
S. aureus N20 (Japan)4 (S)18 (S)1 (S)17 (S)
S. aureus 963sm (Michigan)8 (I)18 (S)16 (I)13 (I)
S. aureus 966 (Michigan)4 (S)16 (S)16 (I)13 (I)
S. aureus 992 (New Jersey)8 (I)17 (S)8 (S)15 (S)
S. aureus803 (Florida)4 (S)17 (S)16 (I)15 (S)
S. epidermidis 5289 (Virginia)8 (I)18 (S)16 (I)14 (S)
S. epidermidis 759 (Wisconsin)8 (I)17 (S)16 (I)14 (S)
S. epidermidis 12333 (California)8 (I)17 (S)16 (I)13 (I)
S. haemolyticus 142 (New York)8 (I)17 (S)32 (R)13 (I)
  • a MICs are measured in micrograms per milliliter. Items in parentheses are NCCLS interpretive categories (S, susceptible; I, intermediate; and R, resistant). A vancomycin MIC of ≤4 μg/ml indicates susceptibility and a vancomycin MIC of ≥32 μg/ml indicates resistance. A teicoplanin MIC of ≤8 μg/ml indicates susceptibility and a teicoplanin MIC of ≥32 μg/ml indicates resistance. Other values are intermediate.

  • b DD, disk diffusion (measured in millimeters). NCCLS interpretive categories are given in parentheses. For vancomycin a zone size of ≥12 mm indicates susceptibility and a zone size of ≤9 mm indicates resistance. For teicoplanin a zone size of ≥14 mm indicates susceptibility and a zone size of ≤10 mm indicates resistance. Other values are intermediate.