Assessment of virulence factors and antifungal susceptibility of Candida species isolated from catheter associated urinary tract infections

Abstract

ABSTRACT Background: Catheter associated urinary tract infection (CAUTI) is a crucial attribute to virulence of organisms. Emergency of non albicans Candida (NAC) species become common due to several virulence factors, which play an important role in pathogenicity and their resistance to treatment. The aim of work: To investigate different virulence factors of Candida spp. isolated from CAUTI patients and evaluate their antifungal susceptibility. Patients and methods: Urine samples collected from 219 indwelling catheters of ICU patients. Candida isolates identified using Germ tube test, Chrom ID agar, Corn meal tween agar, VITEK 2 system and Integral System Yeast Plus (ISYP) used to detect antifungal susceptibility. Enzymatic, haemolytic activity and biofilm formation assessed by standard methods. Results: The incidence of candiduria was 50/219 (22.8%). Candida tropicalis was predominant (54.0%) followed by C. albicans (26.0%) and C. glabrata (20.0%). Females gender (64.0%), Diabetes (50.0%) associated with positive candiduria, while antibiotic therapy was predominant risk factor (78.0%). C. albicans have highest enzymatic activity for phospholipase (84.6 %), proteinase (84.6%) and haemolytic activity (100%), while C. tropicalis have highest biofilm formation (100%). NAC spp. showed higher rates of resistance to azole drugs (Clotrimazole 77.6%, Miconazole 70.3%, Econazole 63.2%, Nystatine 44.3%), while C. albicans didn’t show any resistance. Conclusion: Candiduria is prevalent among catheterized patients with shift toward NAC spp. causing nosocomial UTI. A strong relationship between host risk factors (old age, antibiotic use, catheterization, female sex, ICU stay, diabetes) and expression of various virulence factors of Candida spp. causing candiduria and resistance to antifungal drugs.