Table 2.

Antibiotics, suppliers, disk content and breakpoints used for disk susceptibility testing.

Antibiotic	Supplier	Disk content (μg)	Zone diameter (mm) breakpointsd
			S	I	R
Ampicillina	BD	10	≥17	–	≤16
Doxycyclinea	BD	30	≥16	13–15	≤12
Erythromycina	BD	15	≥23	14–22	≤13
Gentamicina	BD	120	≥10	7–9	6
Levofloxacina	BD	5	≥17	14–16	≤13
Linezolida	BD	30	≥23	21–22	≤20
Nitrofurantoina	BD	300	≥17	15–16	≤14
Quinupristin-dalfopristina	BD	4.5/10.5	≥19	16–18	≤15
Streptomycina	BD	300	≥10	7–9	6
Tigecycline	BD	15	≥18	–	<15
Tylosinb	Medox	30	n/a	n/a	n/a
Vancomycina, c	BD	30	≥17	15–16	≤14

^aM100-S24: Performance standards for antimicrobial susceptibility testing; twenty-fourth informational supplement (Clinical and Laboratory Standards Institute, 2014b).

^bBreakpoint tables for interpretation of MICs and zone diameters. Version 4.0. (The European Committee on Antimicrobial Susceptibility Testing, (EUCAST), 2014).

^cVancomycin requires 24 h incubation while for all other antibiotics 16–18 h incubation is sufficient.

^dZone diameter value used to indicate susceptible (S), intermediate (I), resistant (R) and not available (n/a).