Comparison of agar dilution, broth dilution, and disk diffusion testing of ampicillin against Haemophilus species by using in-house and commercially prepared media.
An evaluation to determine the optimal method for the in vitro susceptibility testing of Haemophilus strains to ampicillin was undertaken. In our hands, in-house-prepared Haemophilus Test Medium used by either the broth macrodilution or agar dilution method produced the most consistent results, especially for beta-lactamase-negative, ampicillin-resistant H. influenzae strains.
Kohner
P C
PC
Department of Laboratory Medicine, Mayo Clinic and Foundation Rochester, Minnesota 55905.
Rosenblatt
J E
JE
Cockerill
F R
FR
D000362:Agar; D000668:Ampicillin Resistance; D003470:Culture Media; D006190:Haemophilus / Q000145:classification / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification; D006193:Haemophilus influenzae / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D015203:Reproducibility of Results
D003470:Culture Media; D000362:Agar