β-Lactamase Production and Antimicrobial Susceptibility of Oral Heterogeneous Fusobacterium nucleatum Populations in Young Children

Abstract

Oral Fusobacterium nucleatum populations from 20 young, healthy children were examined for β-lactamase production. Ten children (50%) harbored, altogether, 25 β-lactamase-positive F. nucleatum isolates that were identified as F. nucleatum subsp. polymorphum , F. nucleatum subsp. nucleatum , and F. nucleatum subsp. vincentii (J. L. Dzink, M. T. Sheenan, and S. S. Socransky, Int. J. Syst. Bacteriol. 40:74–78, 1990). In vitro susceptibility of these β-lactamase-producing and 26 non-β-lactamase-producing F. nucleatum isolates was tested with penicillin G, amoxicillin-clavulanic acid, tetracycline hydrochloride, metronidazole, trovafloxacin, and azithromycin. Except for penicillin G, the antimicrobials exhibited good activity against all F. nucleatum isolates.