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. 1983 Aug;24(2):287–289. doi: 10.1128/aac.24.2.287

Effect of inoculum size on Haemophilus influenzae type b susceptibility to new and conventional antibiotics.

C Laferriere, M I Marks, D F Welch
PMCID: PMC185154  PMID: 6605716

Abstract

Thirty-three Haemophilus influenzae type b isolates, including beta-lactamase acetyltransferase-positive strains, were tested by microtiter broth dilution for susceptibility to eight beta-lactam compounds and chloramphenicol. All antibiotics except ampicillin and chloramphenicol were highly bactericidal against all isolates at an inoculum of 10(5) CFU/ml. However, at an inoculum of 10(5) CFU/ml, the minimal bactericidal concentrations of all drugs except ceftriaxone were above levels usually achievable in cerebrospinal fluid. Results of time-kill studies confirmed this inoculum effect. In vivo studies are needed to test the clinical impact of these observations.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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