Does the adoption of EUCAST susceptibility breakpoints affect the selection of antimicrobials to treat acute community-acquired respiratory tract infections?

Table 4 Antimicrobial susceptibility of M. catarrhalis as classified by CLSI and EUCAST §

Antimicrobial agent^a(n° of strains)	CLSI susceptibility breakpoint (mg/L)	EUCAST susceptibility breakpoint(mg/L)	CLSI %S	EUCAST %S	Type of discrepancy^b
Amoxicillin-clavulanate (3.549)	≤4	≤1	100	99.9	-
Cefaclor (7.536)	≤8	≤0.12	95.1	0.27	very major
Cefuroxime axetil (15.381)	≤4	≤0.125	98.7	1.2	very major
Cefotaxime (2.737)	≤2	≤1	99.9	99.6	-
Ceftriaxone (5.187)	≤2	≤1	99.9	99.1	-
Clarithromycin (910)	≤1	≤0.25	100	99.9	-
Erythromycin (3.038)	≤2	≤0.25	100	99.7	-
Ciprofloxacin (11.119)	≤1	≤0.5	99.9	99.9	-
Levofloxacin (5.239)	≤2	≤1	100	99.9	-
Tetracycline (8.660)	≤2	≤1	97.7	94.8	-

§ CLSI [11] and EUCAST [13].
^aFor Chloramphenicol and Trimethoprim/sulfamethoxazole CLSI and EUCAST suggested the same susceptibility breakpoints.
^b Discrepancy as defined in the materials and methods section.

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