Antifungal Drug Susceptibility Testing of Yeast: A Primer for Beginners

In this month's "Hot Topic," Nancy Wengenack, M.D., reviews the most common methods used by clinical laboratories for antifungal drug susceptibility testing of yeast isolates grown from microbiologic culture, discusses how breakpoints are established, and talks about a value known as the epidemiological cutoff value (ECV) and how those values are established.
0:00 Intro
0:46 Overview
1:21 When Should I Order Susceptibility Testing for a Yeast Recovered in a Culture?
3:43 Antifungal Susceptibility Testing Methods
5:23 CLSI Reference Method of Yeast Susceptibility Testing
7:43 Microbroth Dilution Method Overview
9:18 Determining the MIC
13:17 Breakpoints & Interpretive Criteria from CLSI
14:38 Sample of Breakpoints from M60
15:48 CLSI and EUCAST are Working to Establish Additional Breakpoints Where Possible
17:02 Epidemiological Cutoff Values (ECV)
18:10 CLSI Documents with the Method for ECV Determination (M57) and Current ECV Values for Antifungals (M59)
18:55 ECV Determination
20:11 How are ECVs Established?
21:33 ECVs
23:28 Sample of Yeast ECVs from CLSI M59
24:15 Conclusions
25:10 References