Evaluation of virulence factors of clinical yeast isolates from nosocomial fungal infections with the determination of their antifungal susceptibility profile

Due to an increased resistance to antifungal medicines, the prevalence of hospital-acquired fungal infection has recently increased. This study aimed to determine the virulence features that assist in increasing the pathogenicity of clinical yeast isolates.For this purpose, 61 clinical yeast isolates were usedto examine their enzymatic activity (proteinase, phospholipase, and hemolysin), potential to form biofilms, and antifungal susceptibility patterns. The results indicated that majority of the yeast isolates exhibited potential proteinase activity, with 24.6% exhibiting weak activity, 19.7% moderate activity, and 9.8% high activity, while 45.9% phospholipase activity, with 16.4% weak activity, 24.6% exhibiting moderate activity, and 4.9% strong activity. Whilehemolysin production was demonstrated in 85.2%, that 59.0% were strong, 21.3% moderate, and 4.9% weak. Additionally, it was possible to identify biofilm development, which occurred in 90.2% of isolates. All isolates showed sensitivityto the antifungals tested, with the exception of one Candida glabrataisolate that demonstrated resistance to voriconazol and two Candida parapsilosisisolates resistance to flucytosine. The results also revealed no significant changes in proteinase activity or drug susceptibility profile, but significant variations in phospholipase, hemolysin, and biofilm generation amongst yeast isolates.