Unveiling Profile of Candidemia in a Tertiary Care Hospital in Bihar and Comparing Fluconazole and Amphotericin B Susceptibility Testing Methods in Candida Species by Broth Microdilution vs Vitek2 System

Background: Candidemia is a major healthcare concern, particularly in immunocompromised patients, with an increasing prevalence of nonalbicans Candida species demonstrating antifungal resistance . Rapid and accurate identification of Candida species and antifungal susceptibility testing (AFST) are critical for appropriate management1-6. This study aims to characterize the species distribution of Candida isolates in a tertiary care hospital in Bihar and compare the essential and categorical agreement of Fluconazole and Amphotericin B susceptibility testing using the broth microdilution method versus the automated VITEK 2 system 7-9. Methods: A total of 126 Candida isolates from bloodstream infections were identified using both conventional methods (Gram staining, germ tube test, CHROMagar, Dalmau plate using cornmeal agar, and carbohydrate assimilation and fermentation profiles) and the automated VITEK 2 system (bioMérieux, version 9.02) 1,2. AFST for Fluconazole and Amphotericin B was performed using the Clinical and Laboratory Standards Institute (CLSI) M27/A3 broth microdilution method and the VITEK 2 system (bioMérieux, version 9.02) 8. Essential and categorical agreement between the two methods was assessed 10. Results: Among the isolates, 11.9% were Candida albicans, while 88.1% were non-albicans Candida, with Candida parapsilosis and Candida tropicalis being the most prevalent. The VITEK 2 system demonstrated high reliability, with 100% categorical agreement for Fluconazole and 95.4% for Amphotericin B compared to broth microdilution. Essential agreement was 98.4% for Fluconazole and 60.3% for Amphotericin B. The VITEK 2 system significantly reduced the time required for Candida speciation and susceptibility testing, enabling timely clinical decision-making. Conclusion: Candida speciation and antifungal susceptibility testing are crucial for guiding appropriate therapy and preventing resistance 7. Non-albicans Candida species are emerging as significant pathogens, necessitating accurate identification and susceptibility testing 4-6. The VITEK 2 system enhances Candida identification and antifungal susceptibility determination, offering a rapid and reliable alternative to conventional methods 8-10. With high agreement rates for Fluconazole and Amphotericin B, it serves as an efficient tool for clinical decisionmaking. However, further research is needed to refine susceptibility testing methods and ensure optimal antifungal therapy