Table 2.

Mutant prevention concentration (MPC) of colistin alone and in combination with rifampicin 1.1 mg/L or 4.4 mg/L

Isolate	MPC (mg/L)
	Colistin alone	Colistin + 1.1 mg/L rifampicin	Colistin + 4.4 mg/L rifampicin
AB1	64	8–16	8–16
AB2	64	16	8–16
AB3	16–32	16–32	32
AB4	64	8	8
AB5	64	8–16	8–16