In vitro antibiotic susceptibility testing of Brucella isolates from Egypt between 1999 and 2007 and evidence of probable rifampin resistance

Table 1 MIC ranges, MIC ₅₀ and MIC ₉₀ values of eight antibiotics against Brucella isolates

Antibiotics	Range (μg/ml)	MIC₅₀	MIC₉₀	CLSI Breakpoints for Brucella (μg/ml)
Antibiotics	Range (μg/ml)	MIC₅₀	MIC₉₀	S	I	R
Trimethoprim-Sulfamethoxazole	0.006-0.75	0.047	0.19	≤ 2/38	-	-
Tetracycline	0.023-0.75	0.125	0.19	≤ 1	-	-
Doxycycline	0.016-0.5	0.125	0.25	≤1	-	-
Ciprofloxacin	0.125-0.75	0.25	0.38	≤ 1^a	-	-
Ceftriaxone	0.064-4	0.5	1	≤ 2 ^a	-	-
Streptomycin	0.125-3	1.5	2	≤ 8	-	-
Gentamicin	0.094-3	0.5	1	Not defined
Rifampin	0.25-6	2	4	≤ 1 ^a	2 ^a	≥ 4 ^a

ISSN: 1476-0711