Natural antibiotic susceptibilities of Edwardsiella tarda, E. ictaluri, and E. hoshinae

Antimicrob Agents Chemother. 2001 Aug;45(8):2245-55. doi: 10.1128/AAC.45.8.2245-2255.2001.

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 beta-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.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Databases, Factual
  • Drug Resistance, Microbial
  • Edwardsiella ictaluri / drug effects*
  • Edwardsiella ictaluri / pathogenicity
  • Edwardsiella tarda / drug effects*
  • Edwardsiella tarda / physiology
  • Humans
  • Microbial Sensitivity Tests

Substances

  • Anti-Bacterial Agents