Evaluation of CHROMagar candida for rapid identification and Etest for antifungal susceptibility testing in a district general hospital laboratory

Comparison between E-test and CLSI broth microdilution method for antifungal susceptibility testing of Candida albicans oral isolates

Thirty Candida albicans isolated from oral candidosis patients and 30 C. albicans isolated from control individuals were studied. In vitro susceptibility tests were performed for amphotericin B, fluconazole, 5-flucytosine and itraconazole through the Clinical and Laboratorial Standards Institute (CLSI) reference method and E test system. The results obtained were analyzed and compared. MIC values were similar for the strains isolated from oral candidosis patients and control individuals. The agreement rate for the two methods was 66.67% for amphotericin B, 53.33% for fluconazole, 65% for flucytosine and 45% for itraconazole. According to our data, E test method could be an alternative to trial routine susceptibility testing due to its simplicity. However, it can not be considered a substitute for the CLSI reference method.

Identificação de espécies de Candida e susceptibilidade antifúngica in vitro: estudo de 100 pacientes com candidíases superficiais

FUNDAMENTO: Leveduras do gênero Candida determinam colonização, infecções superficiais e infecções sistêmicas em imunodeprimidos. As várias apresentações da doença levam à necessidade de utilizar diferentes métodos diagnósticos e tratamentos. OBJETIVOS: Diferenciar as espécies de Candida e correlacioná-las com as regiões anatômicas. Avaliar a susceptibilidade a cetoconazol, fluconazol, itraconazol e anfotericina B. MÉTODOS: Foram avaliados 100 pacientes imunocompetentes com candidíase cutânea ou mucosa atendidos na Santa Casa de S. Paulo entre maio de 1999 e julho de 2001. Correlacionou-se a região acometida e a espécie de Candida, isolada através técnica CHROMagar Candida®. Avaliou-se a susceptibilidade das espécies a cetoconazol, fluconazol, itraconazol e anfotericina B, através do Etest®. RESULTADOS: C. albicans foi isolada em 76,0% dos materiais, C. krusei em 19% e C. tropicalis em 1%. Não houve correlação significante entre a região acometida e as espécies. A maioria das amostras mostrou susceptibilidade aos antifúngicos. CONCLUSÃO: C. albicans foi a espécie mais observada. A maioria das amostras de Candida mostrou-se susceptível aos antifúngicos.

Persistence of pigment production by yeast isolates grown on CHROMagar Candida medium

We evaluated the persistence of pigmentation in yeast isolates grown on the chromogenic medium CHROMagar Candida over 7 days. Candida, Cryptococcus, and Trichosporon isolates were inoculated alone or mixed onto duplicate sets of plates and incubated at 30 and 35 degrees C. Candida albicans and Candida krusei were readily identified throughout the reading period, but Candida glabrata was difficult to differentiate from other species until the 3- or 4-day time point. Candida tropicalis produced colonies similar to those of rare Cryptococcus and Trichosporon species, and mixed cultures were often difficult to identify as such.