Electrophoretic karyotyping and triazole susceptibility of Candida glabrata clinical isolates

A series of 35 strains of Candida glabrata isolated from 29 subjects (5 AIDS patients and 24 HIV-seronegative individuals) were typed by electrophoretic karyotyping and tested for their susceptibilities to both fluconazole and itraconazole. Almost every individual harboured his/her own specific isolate (DNA type). Neither the source of isolation nor the patient's HIV status was associated with a given DNA type. Recurrences were generally due to the persistence of the same DNA type over time. Only 9% of the isolates showed reduced susceptibility to fluconazole (MIC > or = 8.0 microg/ml), while 43% of the isolates showed reduced susceptibility to itraconazole (MIC > or = 0.25 microg/ml) (P = 0.02). These data show that electrophoretic karyotyping is a useful technique for DNA typing of isolates of Candida glabrata. Care must be taken prior to initiation of antifungal therapy with either of these drugs.