Presumptive identification of Candida species other than C. albicans, C. krusei, and C. tropicalis with the chromogenic medium CHROMagar Candida.
BACKGROUND
CHROMagar Candida (CaC) is increasingly being reported as a medium used to differentiate Candida albicans from non-albicans Candida (NAC) species. Rapid identification of NAC can assist the clinician in selecting appropriate antifungal therapy. CaC is a differential chromogenic medium designed to identify C. albicans, C. krusei, and C. tropicalis based on colony color and morphology. Some reports have proposed that CaC can also reliably identify C. dubliniensis and C. glabrata.


METHODS
We evaluated the usefulness of CaC in the identification of C. dubliniensis, C. famata, C. firmetaria, C. glabrata, C. guilliermondii, C. inconspicua, C. kefyr, C. lipolytica, C. lusitaniae, C. norvegensis, C. parapsilosis, and C. rugosa.


RESULTS
Most NAC produced colonies that were shades of pink, lavender, or ivory. Several isolates of C. firmetaria and all C. inconspicua produced colonies difficult to differentiate from C. krusei. Most C. rugosa isolates produced unique colonies with morphology like C. krusei except in a light blue-green color. C. glabrata isolates produced small dark violet colonies that could be differentiated from the pink and lavender colors produced by other species. All seventeen isolates of C. dubliniensis produced green colonies similar to those produced by C. albicans.


CONCLUSIONS
C. glabrata and C. rugosa appear distinguishable from other species using CaC. Some NAC, including C. firmetaria and C. inconspicua, could be confused with C. krusei using this medium.
Hospenthal
Duane R
DR
Department of Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas, USA. duane.hospenthal@amedd.army.mil
Beckius
Miriam L
ML
Floyd
Karon L
KL
Horvath
Lynn L
LL
Murray
Clinton K
CK
D000362:Agar; D000935:Antifungal Agents / Q000145:classification / Q000302:isolation & purification / Q000494:pharmacology*; D002175:Candida / Q000145:classification* / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D002176:Candida albicans / Q000254:growth & development / Q000302:isolation & purification*; D041221:Candida glabrata / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D041022:Candida tropicalis / Q000254:growth & development / Q000302:isolation & purification*; D003470:Culture Media; D008826:Microbial Sensitivity Tests; D014774:Virulence
D000935:Antifungal Agents; D003470:Culture Media; D000362:Agar