Comparison of the Etest and a microbroth dilution system (Sceptor) to a reference agar dilution method for susceptibility testing of Bilophila wadsworthia.
OBJECTIVE: To compare the Etest and a microbroth dilution system (Sceptor) to a reference agar dilution method for susceptibility testing of Bilophila wadsworthia. METHODS: The susceptibility of 15 clinical isolates of Bilophila wadsworthia was determined by the National Committee for Clinical Laboratory Standards (NCCLS) agar dilution method using triphenyltetrazolium chloride for endpoint determination. The results were compared with the results obtained by the E test and a commercial microbroth dilution system (Sceptor). RESULTS: Comparison of the MICs obtained by the reference method and the Etest revealed few discrepancies, with piperacillin and metronidazole being the only exceptions. The overall agreement was 70% within one dilution step. The discrepancies did not result in major interpretative errors. The overall essential agreement using susceptibility categories was 98% for the E test and 99% for the microdilution system. CONCLUSIONS: Both methods may be considered as acceptable alternatives for testing individual isolates of B. wadsworthia.
Schumacher
Ulrike K.
UK
Department of Medical Microbiology, Institute of Hygiene, University of Tübingen, Tübingen, Germany.