Table 6.

Results of testing with vancomycin screening agar prepared in-house

Screening plate content and isolate descriptionNo. of plates positive/total no. tested with mediuma:
AcumediaBBLDifcoOxoidRemel
Vancomycin, 6 μg/ml
 Vancomycin MIC = 8 μg/ml7/87/88/88/87/8
 Vancomycin MIC = 4 μg/ml1/3b 2/3b 1/3b 1/3b 1/3b
 Vancomycin MIC ≤ 2 μg/ml0/25c 1/251/252/252/25
E. faecalis ATCC 51299d 3/33/33/33/33/3
E. faecalis ATCC 29212d 0/31/30/30/31/3
S. aureus ATCC 29213d 0/33/30/32/31/3
S. aureus ATCC 25923d 0/30/30/30/30/3
Vancomycin, 4 μg/ml
 Vancomycin MIC = 8 μg/ml8/87/88/88/88/8
 Vancomycin MIC = 4 μg/ml1/32/31/31/31/3
 Vancomycin MIC ≤ 2 μg/ml3/257/252/253/2513/25
E. faecalis ATCC 512993/33/33/33/33/3
E. faecalis ATCC 292120/30/30/31/33/3
S. aureusATCC 292132/33/33/33/33/3
S. aureus ATCC 259230/30/30/30/30/3
Vancomycin, 2 μg/ml
 Vancomycin MIC = 8 μg/ml8/88/88/88/88/8
 Vancomycin MIC = 4 μg/ml3/33/33/33/33/3
 Vancomycin MIC ≤ 2 μg/ml13/2524/2521/2522/2524/25
E. faecalis ATCC 512993/33/33/33/33/3
E. faecalis ATCC 292123/33/33/33/33/3
S. aureusATCC 292133/33/33/33/33/3
S. aureus ATCC 259231/32/32/33/33/3
  • a Sources of the media used for the screening plates are given.

  • b S. aureus 966 (from Michigan), for which the vancomycin MIC was 4 μg/ml and for which the teicoplanin MIC was 16 μg/ml, was positive on all media.

  • c Includes Mu3 (from Japan; reference MIC = 2 μg/ml).

  • d Quality control isolates. Each isolate was tested three times.