Tehran University of Medical Sciences

Science Communicator Platform

Stay connected! Follow us on X network (Twitter):
Share this content! On (X network) By
Virulence Factors and Azole-Resistant Mechanism of Candida Tropicalis Isolated From Candidemia Publisher



Sasani E1 ; Yadegari MH1 ; Khodavaisy S2 ; Rezaie S2 ; Salehi M3 ; Getso MI2, 4
Authors
Show Affiliations
Authors Affiliations
  1. 1. Department of Medical Mycology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
  2. 2. Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
  3. 3. Department of Infectious Diseases and Tropical Medicine, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
  4. 4. Department of Medical Microbiology and Parasitology, College of Health Sciences, Bayero University, Kano, Nigeria

Source: Mycopathologia Published:2021


Abstract

Background: Limited knowledge exists on the virulence factors of Candida tropicalis and the mechanisms of azole resistance that lead to an intensified pathogenicity and treatment failure. We aimed to evaluate the virulence factors and molecular mechanisms of azole resistance among C. tropicalis isolated from patients with candidemia. Materials and Methods: Several virulence factors, including extracellular enzymatic activities, cell surface hydrophobicity (CSH), and biofilm formation, were evaluated. Antifungal susceptibility pattern and expression level of ERG11, UPC2, MDR1, and CDR1 genes of eight (4 fluconazole resistance and 4 fluconazole susceptible) clinical C. tropicalis isolates were assessed. The correlation between the virulence factors and antifungal susceptibility patterns was analyzed. Results: During a 4 year study, forty-five C. tropicalis isolates were recovered from candidemia patients. The isolates expressed different frequencies of virulence determinants as follows: coagulase 4 (8.9%), phospholipase 5 (11.1%), proteinase 31 (68.9%), esterase 43 (95.6%), hemolysin 44 (97.8%), biofilm formation 45 (100%) and CSH 45(100%). All the isolates were susceptible to amphotericin B and showed the highest resistance to voriconazole. There was a significant positive correlation between micafungin minimum inhibitory concentrations (MICs) and hemolysin production (rs = 0.316). However, we found a negative correlation between fluconazole MICs and esterase production (rs = −0.383). We observed the high expression of ERG11 and UPC2 genes in fluconazole-resistant C. tropicalis isolates. Conclusion: C. tropicalis isolated from candidemia patients extensively displayed capacities for biofilm formation, hemolysis, esterase activity, and hydrophobicity. In addition, the overexpression of ERG11 and UPC2 genes was considered one of the possible mechanisms of azole resistance. © 2021, The Author(s), under exclusive licence to Springer Nature B.V.
Experts (# of related papers)
Other Related Docs