Typing of Candida Strains Straightened from Immunesupressed Patients and Investigation of Their Sensitivity to Antifungal Drugs by E-Test Method

Objective: Investigation of the Antifungal Susceptibility of Candida Strains Isolated from Immune Suppressed Patients, with E test Method It is well-known that Candida causes a considerable mortality via leading invasive and disseminated-systemic infections in the patients whose immune suppressed or in poor clinic condition.

Materials and Methods: In this study, it was aimed to investigate typing of Candida species that were isolated from various clinic samples from inpatients whose immune-suppressed or in poor clinic condition and also to determine the antifungal susceptibility of these isolates. During the study, a total 46 Candida were isolated from urine (6), sputum (6), blood (11), wound (4), endotracheal aspirate (7), nasopharynx (3), catheter (7) and stool (2) samples of 39 febrile neutropenic patients and 7 patients with poor clinic condition in intensive care units. Typing of the Candida isolates were carried out with API ID 32 C (bio Mérieux) kits. Antifungal susceptibility was determined with the E test (AB Biodisk, Sweden).

Result: Of the strains included into the study, 24 (52.1%) were identified as Candida albicans, five (10.8%) were Candida krusei, seven (15.2 %) were Candida tropicalis, four (8.6 %) were Candida glabrata, three (6.5 %) were Candida parapsilosis and three (6.5%) were Candida guillermondii. In the susceptibility assay with E test, 2.1% of the isolates were found resistant to amphotericin B, 21.7 % to ketoconazole and fluconazole, 17.3 % to voriconazole, 23.9% to itraconazole and 6.5 % to flucytosine. The MIC50 and MIC90 values of the most active antifungal, amphotericin B, were determined as 0.019 and 0.75 μg/ml, respectively; and the MIC50 and MIC90 values of the least active antifungal, itraconazole, were determined as 0.032 and 16 μg/ml, orderly.

Conclusion: Due to development of the medicine, the target patient population of Candida, which is an opportunistic pathogen, is progressively augmented, and by the time, it is observed that the prevalence of the invasive candida infections are being increased. Therefore, to successfully treat the serious infections caused by Candida in the patients at high risk, typing of the Candida should be routinely performed and antifungal susceptibility of these strains should be investigated with a reliable method, regularly.

Keywords: Candida strains; Amphotericin B; Voriconazole; Ketoconazole; Itraconazole; Fluconazole; Flucytosine; Antifungal susceptibility