Affiliation:
1. Institute of Medical Microbiology and Immunology, Pharmaceutical Microbiology, University of Bonn, Bonn, Germany
Abstract
ABSTRACT
The natural antibiotic susceptibilities to 71 antibiotics of 102
Edwardsiella
strains belonging to
E. tarda
(
n
= 42),
E. ictaluri
(
n
= 41), and
E.
hoshinae
(
n
= 19) were investigated. MICs were determined using a microdilution procedure according to NCCLS criteria and German standards. All edwardsiellae were naturally sensitive to tetracyclines, aminoglycosides, most β-lactams, quinolones, antifolates, chloramphenicol, nitrofurantoin, and fosfomycin.
Edwardsiella
species were naturally resistant to macrolides, lincosamides, streptogramins, glycopeptides, rifampin, fusidic acid, and oxacillin. Although slight species-dependent differences in natural susceptibilities to some antibiotics (e.g., macrolides and cefaclor) were seen, differences in natural susceptibility affecting clinical assessment criteria were only seen with benzylpenicillin. Whereas
E. tarda
was naturally resistant to benzylpenicillin,
E. hoshinae
was naturally sensitive. Natural sensitivity and resistance to this penicillin were found among the strains of
E. ictaluri.
The observed oxacillin sensitivity of
E. ictaluri
was attributed to the failure of the species to grow at higher salt concentrations found in oxacillin-containing microtiter plates. The present study describes a database concerning the natural susceptibility of
Edwardsiella
species to a wide range of antibiotics, which can be applied to validate forthcoming antibiotic susceptibility tests of these microorganisms.
Publisher
American Society for Microbiology
Subject
Infectious Diseases,Pharmacology (medical),Pharmacology