Abstract: Objective Study on the broth microdilution antifungal susceptibility testing condition about 182 Microsporum canis derived from patients in Beijing Children's Hospital.Methods The vitro method was used for testing filamentous fungi.We approached the broth microdilution antifungal susceptibility testing condition for Microsporum canis and tested the minimal inhibitory concentration(MIC) of 8 common antifungal drugs.Results The broth microdilution antifungal susceptibility testing condition for Microsporum canis: inoculum size ranged from 1×10⁴ to 3×10⁴ CFU/mL;MICs obtained from different medium at the same incubation time for the same isolate were significantly different,MICs were consistently higher with SDB than with RPMI-1640,when itraconazole,bifonazole,amorolfine were tested,no parameter had any influence on MICs;incubation temperature was 28 ℃,Microsporum canis produced clearly detectable growth after 5 d.Conclusion With good reproducibility and feasibility,the M38A procedure can be used for the antifungal susceptibility test to dermaphytes in the laboratories.

Key words: Microsporum canis, susceptibility test, M38-A procedure