TABLE 1.

Tigecycline MICs determined by different methods, inhibition zone diameter determinations (disc diffusion), and susceptibility categorization using different media for E. coli ATCC 25922 (five replicates for each method with each medium)^a

Medium	Etest MIC (μg/ml) [modal value (range)]	Disc diffusion zone diam (mm; mean ± SD)b	Broth dilution MIC (μg/ml) [modal value (range)]	Agar dilution MIC [modal value (range)]
Difco	0.09 (0.09-0.12)	25.9 ± 0.3	0.12 (0.12-0.25)	0.25 (0.25-0.25)
Merck	0.09 (0.09-0.09)	26.8 ± 0.2	0.25 (0.25-0.5)	0.12 (0.12-0.12)
Remel	0.19 (0.19-0.19)	24.8 ± 0.3	0.25 (0.25-0.5)	0.5 (0.25-0.5)
BBL	0.19 (0.19-0.25)	24.0 ± 0.2	0.12 (0.12-0.25)	0.25 (0.25-0.25)
Oxoid	0.19 (0.19-0.19)	22.3 ± 0.1*	0.25 (0.25-0.5)	0.5 (0.25-0.5)
bioMérieux	0.25 (0.25-0.38)	21.9 ± 0.4*

^aBSAC/EUCAST results are represented as follows: no symbol, susceptible; asterisk, intermediate. The BSAC/EUCAST MIC susceptibility and resistance breakpoints were ≤1 μg and ml≥4 μg/ml; the BSAC/EUCAST disc diffusion zone diameter susceptibility and resistance breakpoints were ≥24 mm and ≤19 mm.

^bMean values were rounded up or down to the nearest digit for susceptibility interpretations.