Comparison of results obtained by testing with three different agar media and by the NCCLS M27-A method for in vitro testing of fluconazole against Candida spp.
Fluconazole susceptibilities of 150 Candida isolates were determined by a 25- micro g fluconazole disk diffusion agar test and compared with the microdilution NCCLS M27-A method. The agar test used three different media and was read at 24 and 48 h. When only the susceptible and nonsusceptible categories were used, disk diffusion with Müeller-Hinton agar supplemented with 2% glucose and 0.5 micro g of methylene blue (MHGM) per ml had a 95.37% correlation with the MIC method at 24 h, followed by RPMI 1640-2% of glucose agar (correlation, 94%) and Shadomy medium (SHDM) (correlation, 92.6%). The growth of microcolonies inside the inhibition zones was common (>63%) in the RPMI and SHDM media and minimal with MHGM (8.7%). At 48 h, MHGM and SHDM still had a >91% correlation with the MIC, while RPMI results had dropped to 75%. The best overall agreement was obtained with C. dubliniensis (100%).
Rubio
M Carmen
MC
Microbiology, Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain. mcrubio@posta.unizar.es
Gil
Joaquina
J
De Ocáriz
Inmaculada Ramírez
IR
Benito
Rafael
R
Rezusta
Antonio
A
D000362:Agar; D000935:Antifungal Agents / Q000494:pharmacology*; D002175:Candida / Q000145:classification / Q000187:drug effects* / Q000254:growth & development*; D003470:Culture Media; D015725:Fluconazole / Q000494:pharmacology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods
D000935:Antifungal Agents; D003470:Culture Media; D015725:Fluconazole; D000362:Agar