Mycological Profile of Candida tropicalis and its Virulence Factors from Candidemia Patients at A Tertiary Care Facility

Abstract

Candida tropicalis is the fourth main infective agent of Candida species in several developing nations and leads to the greatest fatality rate among the non-albicans Candida (NAC) species that cause candidemia. Seventy clinically known Candida isolates are isolated in positively flagged blood samples from BacT/ALERT 3D from various wards. Virulence factors like hemolysin production, coagulase activity, phospholipase activity, and biofilm formation were studied and antifungal susceptibility testing was and Minimum Inhibitory Concentration (MIC) values were interpreted. Of the total 70 clinical Candida isolates, the most predominant organism isolated was found to be C. tropicalis 27 (38.57%) which is succeeded by 19 (27.14%) C. albicans, 13 (18.57%) C. parapsilosis, 6 (8.57%) C. glabrata, and 5 (7.14%) C. krusei respectively. Among the70 Candida isolates, 49 (70%) showed hemolysin production, 43 (61.42%) isolates demonstrated phospholipase activity, 34 (48.57%) showed coagulase activity and 55 (78.57%) isolates showed biofilm production by crystal violet assay. A high level of Fluconazole resistance has been observed in 23 (32.85%) Candida isolates in comparison with other antimicrobials utilized in this study. The higher MIC value of: ≥ 64 µg/mL Fluconazole was shown by 4 (57.14%) isolates of C. tropicalis by broth microdilution method. The interpretation of various virulence factors and antifungal drug resistance were seen mostly among NAC species, thus hence signifying its pivotal role in immunocompromised individual treatment.

Keywords

• candida tropicalis
• candidemia
• virulence factors
• antifungal drug resistance