Antimicrobial susceptibility testing of Arcobacter butzleri: development and application of a new protocol for broth microdilution.

Objectives: To develop a standard reference broth microdilution method for antimicrobial susceptibility testing (AST) of Arcobacter butzleri. The protocol was subsequently applied to a collection of A. butzleri isolates from different sources.

Susceptibility testing of Rhodococcus equi: An interlaboratory test.

Due to the importance of antimicrobial susceptibility testing (AST) for veterinary diagnostics, a standardised protocol for AST of Rhodococcus equi by broth microdilution has recently been developed and approved by the Clinical and Laboratory Standards Institute (CLSI). The aim of the present study was to test this protocol in an interlaboratory comparative study for its fitness for use in routine laboratory diagnostics. All of the 18 participating laboratories determined the minimum inhibitory concentrations (MIC) of two R.

[Antimicrobial resistance, ESBL and MRSA--definitions and laboratory diagnostics].

In the light of frequent discussions about the correct performance of in vitro susceptibility testing and the interpretation of the results obtained, the aim of the present report is to summarize basic facts that may facilitate the understanding of this complex topic. For this, the terms "antimicrobial resistance", "ESBL", and "MRSA" are defined. Besides the statements on antimicrobial resistance, information on intrinsic and acquired resistance properties as well as basic rules for the correct performance of antimicrobial susceptibility testing in routine diagnostics are presented.

MICs of 32 antimicrobial agents for Rhodococcus equi isolates of animal origin.

Objectives: The aim of this study was to determine the MICs of 32 antimicrobial agents for 200 isolates of Rhodococcus equi of animal origin by applying a recently described broth microdilution protocol, and to investigate isolates with distinctly elevated rifampicin MICs for the genetic basis of rifampicin resistance.

Methods: The study included 200 R. equi isolates, including 160 isolates from horses and 40 isolates from other animal sources, from the USA and Europe.