Cross-Sectional Study of Candidemia from Isfahan, Iran: Etiologic Agents, Predisposing Factors, and Antifungal Susceptibility Testing

Abstract

BACKGROUND: Candidemia is a fatal invasive fungal infection that involves thousands of patients annually and is associated with high mortality rate and economic burden. The incidence of candidemia is increasing due to the use of invasive medical instruments and immunosuppressive drugs. The treatment of infection is problematic because of the increased resistance of clinical strains to antifungal drugs. The aim of the present study was to identify Candida species isolated from candidemia and determination of antifungal susceptibility patterns of clinical isolates. MATERIALS AND METHODS: Three thousand eight hundred BACTEC bottles suspected to candidemia were evaluated from April 2019 to June 2020. For primary identification, a positive blood culture was subcultured onto the sabouraud glucose agar and CHROMagar™ Candida. For molecular identification, ITS1-5.8SrDNA-ITS2 region was amplified by ITS1 and ITS4 primers and MspI restriction enzyme was applied to digest polymerase chain reaction amplicons. Minimum inhibitory concentration of seven antifungals was determined against clinical isolates by broth microdilution method in accordance with the Clinical and Laboratory Standards Institute M27-A3 and M27-S4 documents. RESULTS: Forty-six out of 3800 suspected specimens were positive for candidemia (1.2). The age range of the patients was between 11 days and 89 years, with a median age of 34.8 years. Candida albicans was found to be the most Candida species (58.7), followed by C. parapsilosis complex (19.6), C. glabrata complex (8.7), C. krusei (6.5), C. famata (4.3), and C. tropicalis (2.2). Resistance to amphotericin B, fluconazole, itraconazole, and voriconazole was detected in 13.6, 11.3, 6.8, and 4.5 of clinical isolates, respectively. CONCLUSION: The incidence of non-albicans Candida species is increasing that must be highlighted. Since resistant Candida strains are found repeatedly, consecutive tracing of the species distribution and in vitro antifungal susceptibility of clinical isolates is recommended for better management of infections.