A Study on Virulence Determinants of Clinical Isolates of Candida Species and Their Correlation with Antifungal Resistance in a Tertiary Care Hospital in Eastern India

ABSTRACT

Candida Species are normal flora of skin and mucosa of gastrointestinal tract (GIT) and genital region. Usually they invade host tissue and cause diseases in patients with impaired immunity. OBJECTIVE: The aim of this study is to determine virulence factors expressed by various clinical isolates of different Candida species and to correlate with their antifungal resistance pattern. Methods: A total of 120 Candida isolates obtained from different clinical samples and speciated by standard microbiological laboratory protocol. Haemolysin, phospholipase and esterase activities were detected by growth characteristics on SDA with blood, egg yolk agar medium and Tween- 80 opacity test medium respectively. Adherence was seen microscopically over buccal epithelial cell and biofilm formation was detected visually with 2% Safranin staining. Antifungal susceptibility was detected by disk diffusion method using Mueller Hinton Agar supplemented with glucose and methylene blue (As per CLSI guideline). Results: Out of 120 isolates, 51(42.50%) were C.albicans and 69 (57.5%) were Non albicans Candida (NAC) including C.tropicalis 32(26.67%), C. guilliermondii 21(17.50%), C. parapsilosis 12(10%) and C. glabrata 04(3.33%). Haemolysin, phospholipase and esterase activities were detected in 110 (91.67%), 95 (79.17%) and 82 (68.33%) respectively. Adherence seen in 98 (81.67%) and in 59 (49.17%) cases biofilm had formed. The antifungal susceptibility patterns revealed that 81 (67.5%) were susceptible to Fluconazole and 72 (60%) were susceptible to Itraconazole, whereas 100% were susceptible to Voriconazole and Amphotericin B. Conclusion: Detection of virulence factor will help in better understanding of the changing behavioural patterns of Candida isolates and open doorways to better management and assessing prognosis of the patients.