Nontypeable Haemophilus influenzae susceptibility: effect of inoculum size and beta-lactamase production.
The activities of cefixime, cefpodoxime, cefprozil, cefuroxime, loracarbef, and amoxicillin/clavulanate against 72 clinical isolates of nontypeable Haemophilus influenzae were determined by using an agar dilution method. The effects of beta-lactamase production and bacterial inoculum size were investigated. All antimicrobials exhibited a significant inoculum effect, demonstrating the importance of accurately determining inoculum size in the performance of antimicrobial susceptibility testing of H. influenzae.
Gould
J M
JM
Department of Pediatrics, Allegheny University of Health Sciences, St. Christopher's Hospital for Children, Philadelphia, Pennsylvania 19129, USA.
Heidecker
G J
GJ
LiPuma
J J
JJ
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015169:Colony Count, Microbial; D006193:Haemophilus influenzae / Q000187:drug effects*; D008826:Microbial Sensitivity Tests / Q000379:methods*; D047090:beta-Lactams
D000900:Anti-Bacterial Agents; D047090:beta-Lactams