Identification of Candida Species from Blood Cultures with Fluorescent In Situ Hybridization (FISH), Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Conventional Methods

Objectives: Rapid and accurate identification of Candida species from blood cultures is crucial to ensure effective antifungal therapy and to reduce the morbidity and mortality associated with bloodstream fungal infections. In this study, we aimed to identify Candida spp. from blood culture samples with fluorescent in situ hybridization (FISH), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and conventional methods. Materials and Methods: A total of 50 yeast positive samples out of 325 blood culture positive samples and 50 blood culture negative samples were examined by FISH, PCR-RFLP and conventional methods to identify Candida spp. Results: All three methods generally were compatible for identification of single-species Candida spp. (p<0.001). But, FISH and PCR-RFLP for the identification of multi-species Candida spp. were found more compatible than conventional methods (p<0.001). Besides, FISH is cheaper and quicker than the other two methods in the identification of Candida spp. from blood culture positive samples. The rates of multi-species candidemia with FISH, PCR-RFLP and conventional methods were 20%, 6% and 4%, respectively. Conclusion: Both PCR-RFLP and FISH methods might be preferred for the rapid identification of Candida spp. from blood culture positive samples. However, FISH is a more suitable method for the detection of multi-species candidemia.