Variables Influencing Susceptibility Testing of Cryptococcus neoformans to 5-Fluorocytosine

AUTOR(ES)

Block, Edward R.

RESUMO

The minimum inhibitory concentration (MIC) of 5-fluorocytosine (5-FC) was determined for 65 isolates of Cryptococcus neoformans by using a twofold serial tube dilution method. The MIC was profoundly influenced by incubation temperature, inoculum size, and duration of incubation. By using a standard set of test conditions, 100% of 49 pretreatment isolates of C. neoformans were susceptible to 10 μg of 5-FC per ml or less, and 9 (56%) of 16 isolates recovered during or after 5-FC therapy were massively drug resistant (MIC > 320 μg/ml). With the standard test conditions recommended here, the tube dilution method was found to be both accurate and reproducible, and the results correlated with the treatment status of patients.

Documentos Relacionados

• 5-Fluorocytosine Resistance in Cryptococcus neoformans
• In Vivo Susceptibility of Cryptococcus neoformans to Hamycin, Amphotericin B, and 5-Fluorocytosine 1
• Comparative Study of Trichothecin, Amphotericin B, and 5-Fluorocytosine Against Cryptococcus neoformans In Vitro and In Vivo
• Radiometric Method for Determining the Susceptibility of Yeasts to 5-Fluorocytosine
• Comparison of Microdilution and Broth Dilution Techniques for the Susceptibility Testing of Yeasts to 5-Fluorocytosine and Amphotericin B