TABLE 1.

Broth and agar media used to test ampicillin susceptibility of H. influenzae

Broth or agar	Medium	Supplements
Broths
HTM	CAMHBa	Hematin (15 μg/ml), yeast extract (5 μg/ml), and NADb
LHB	CAMHB	3% lysed horse blood and NAD
Agars
HTM	MHAc	Hematin (15 μg/ml), yeast extract (5 μg/ml), and NAD
LHB	MHA	3% lysed horse blood and NAD
WHB	MHA	5% whole horse blood and NAD
Chocolate	MHA	1% hemoglobin and 1% IsoVitalex
Fildes	MHA	3% Fildes peptic digest of sheep blood
Iso-Sensitest	Iso-Sensitest agar	5% whole horse blood and NAD

^aCAMHB, cation-adjusted Mueller-Hinton broth. 

^bFor the addition of NAD, 20 μg/ml was used. 

^cMHA, Mueller-Hinton agar.