TABLE 2.

Results for ERY-resistant and CC-intermediate or -resistant strains compared to D-zone test resultsa

BacteriaD-zone test result (no. of isolates)Medium% of growth with the ERY-CC concn combinations shown at:
18-h incubation24-h incubation
4 μg/ml and 0.5 μg/ml6 μg/ml and 1 μg/ml8 μg/ml and 1.5 μg/ml0.5 μg/ml and 2 μg/ml4 μg/ml and 0.5 μg/ml6 μg/ml and 1 μg/ml8 μg/ml and 1.5 μg/ml0.5 μg/ml and 2 μg/ml
S. aureusPositive (181)198.3959525.410010098.331
298.998.397.22610010099.530
398.998.997.22610010010030
Negative (152)10.70.70.700.70.70.70.7
20.70.70.700.70.70.70.7
31.30.70.701.30.70.70.7
CoNSPositive (51)110090.288.266.71001009870.6
29894.190.270.610010010072.6
39894.192.270.610010010074.5
Negative (46)12.20002.2000
200002.2000
300000000
  • a Results are shown for strains that are ERY resistant (MICs ≥ 8 μg/ml) and CC intermediate or resistant (MICs ≤ 2 μg/ml) as percentages of growth in ERY-CC combination wells compared to the D-zone test results. Medium 1, BBL CAMHB; 2, Difco CAMHB; 3, Oxoid CAMHB.