TABLE 1.

Comparison of ciprofloxacin and levofloxacin MIC breakpoints

Gram-negative organism and FQ	MIC breakpoints (μg/ml)a
	2019 CLSI breakpoints (4)	2018 CLSI breakpoints (48)	EUCAST breakpoints (5)
Enterobacteriaceae
Ciprofloxacin	S, ≤0.25; I, 0.5; R, ≥1	S, ≤1; I, 2; R, ≥4	S, ≤0.25; R, >0.5
Levofloxacin	S, ≤0.5; I, 1; R, ≥2	S, ≤2; I, 4; R, ≥8	S, ≤0.5; R, >1
P. aeruginosa
Ciprofloxacin	S, ≤0.5; I, 1; R, ≥2	S, ≤1; I, 2; R, ≥4	S, ≤0.5; R, >0.5
Levofloxacin	S, ≤1; I, 2; R, ≥4	S, ≤2; I, 4; R, ≥8	S, ≤1; R, >1

^aS, susceptible; I, intermediate; R, resistant.