Use of CSP typing for genotyping of azole-resistant and -susceptible Aspergillus fumigatus isolates in Iran

H Badali1, M Falahatinejad1, S Khodavaisy2, JF Meis3

Author address: 

1Department of Medical Mycology and Parasitology/Invasive Fungi Research Center (IFRC), School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran 2Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 3Department of Medical Microbiology and Infectious Diseases, Canisius-Wilhelmina Hospital (CWZ), Nijmegen, the Netherlands

Abstract: 

Purpose: Aspergillus fumigatus is the leading cause of mortality in severely immunocompromised individuals. Understanding pathogen dispersion and relatedness is essential for determining the epidemiology of nosocomial infections. Therefore, the aim of this study was to investigate the diversity and putative origins of clinical and environmental azole-susceptible and -resistant A. fumigatus isolates from Iran

Methods: Seventy-nine isolates, including 64 azole-susceptible and 15 azole-resistant isolates, were genotyped using the cell surface protein (CSP) gene

Results: Seven distinct repeat types (r01, r02, r03, r04, r05, r06 and r07) and 11 different CSP variants (t01, t02, t03, t04A, t06A, t06B, t08, t10, t18A, t18B and t22) were observed. Interestingly t06B, t18A and t18B were exclusively present in azole-resistant isolates. The Simpson’s index of diversity (D) was calculated at 0.78. Resistant isolates were genetically less diverse than azole-susceptible isolates. However, azole-resistant A. fumigatus without TR34/L98H were more diverse than with TR34/L98H.

Conclusion: The limited CSP type diversity of the TR34/L98H isolates versus azole- susceptible isolates suggests that repeated independent emergence of the TR34/L98H mechanism is unlikely. It has been suggested that CSP types might have a common ancestor that developed locally and subsequently migrated worldwide.

2018

abstract No: 

154

Full conference title: 

The 8th Advances Against Aspergillus, Lisbon Conference Center, Lisbon, Portugal
    • AAA 8th (2018)