The Agar Diffusion Method in Susceptibility Testing of Yeast

Rosco Diagnostica has a extensive range of Neo-Sensitabs with antifungal agents. A standardized agar diffusion method has been developed using Neo-Sensitabs with antifungals and modified Shadomy Agar or supplemented RPMI-1640 agar.

The agar diffusion method yields a quantitative result (zone of inhibition) and a qualitative interpretation category according to breakpoints. Antifungal susceptibility testing is more complicated than antibacterial susceptibility testing.

CLSI has established a standard method for Antifungal disk diffusion susceptibility testing of Candida spp.


Antifungal susceptibility testing of yeasts is more complicated than antibacterial susceptibility testing on 3 important parameters:

– Density of the inoculum
– Incubation time
– Criteria for measuring zone sizes

In the Neo-Sensitabs Users Guides we are providing details, information and guidance on above parameters.

The folder – Susceptibility Testing of Yeasts – is intended to give the user practical guidance and examples on the procedure and how to read the zones.

Antifungal agents

Widest range available – local and systemic antifungals.
Includes the newest antifungal agents: Caspofungin (research-use-only).
Usable with all recommended media – clear zones – easy to read.

Widest range available
The current range includes the following groups of antifungal agents:

  • Imidazole
  • Triazole
  • Antimetabolites
  • Polyenes
  • Allylamines
  • Echinochandins