Epidemiological Cutoffs and Cross-Resistance to Azole Drugs in Aspergillus fumigatus

DOI: 10.1128/AAC.00156-08

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FIG. 1.
MIC distribution for itraconazole, voriconazole, ravuconazole, and posaconazole for all strains except those with an itraconazole MIC of ≥8 mg/liter.

TABLE 1.

Geometric means and ranges of MICs obtained at 24 and 48 h for A. fumigatus isolates susceptible and resistant to azole drugs

Isolate type and mechanism of resistance	Itraconazole		Voriconazole		Ravuconazole		Posaconazole
Isolate type and mechanism of resistance	GM (range)	MIC₉₀	GM (range)	MIC₉₀	GM (range)	MIC₉₀	GM (range)	MIC₉₀
Susceptible (n = 361)	0.32 (0.06-2)	0.5	0.53 (0.06-2)	1	0.60 (0.06-2)	1	0.08 (0.015-2)	0.125
Resistant (n = 32)
G54 mutation^a (n = 9)	16 (16-16)		0.42 (0.12-1)		0.32 (0.12-1)		1.6 (0.25-16)
M220 mutation^b (n = 6)	16 (16-16)		1.0 (0.5-2)		1.85 (1-4)		0.65 (0.25-2)
TR^c (n = 17)	16 (16-16)		3.7 (2-8)		6.8 (4-16)		0.68 (0.5-8)

↵ a At position 54, nine strains had a substitution of glycine for valine (three), glutamic acid (three), arginine (one), or tryptophan (two).
↵ b At position 220, six strains had a substitution of methionine for valine (three), lysine (one), threonine (one), or isoleucine (one).
↵ c At position 98, 17 strains had a substitution of leucine for histidine and two copies of a 34-bp sequence in tandem in the promoter of the cyp51A gene were present.