Maria F Gonzalez-Lara1, Carla M Roman-Montes1, Paulette Diaz-Lomeli1, Andrea Rangel-Cordero1, Maria O Valenzuela1, Alfredo Ponce-de-Leon1, Jose Sifuentes-Osornio2, Luis Ostrosky-Zeichner3,4, Areli Martinez-Gamboa1. 1. Clinical Microbiology Laboratory, Instituto Nacional de Ciencias Médicasy Nutrición Salvador Zubirán, 15 Vasco de Quiroga Ave, Belisario Domínguez Sección XVI, Tlalpan, México City, México. 2. Department of Medicine, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, 15 Vasco de Quiroga Ave, Belisario Domínguez Sección XVI, Tlalpan, México City, México. 3. Department of Medicine, University of Texas Health Medical School, Houston, TX, USA. 4. Department of Epidemiology, Memorial Hermann Texas Medical Center, Houston, TX, USA.
Abstract
BACKGROUND: Fungicide exposure in the environment has driven the emergence of azole-resistant Aspergillus fumigatus worldwide. A screening test allows identification of resistant isolates. OBJECTIVES: We screened clinical samples for azole-resistant Aspergillus through azole-containing agar plates and identified mutations in the cyp51A gene of A. fumigatus. METHODS: Aspergillus isolates from clinical samples collected in a tertiary care centre from 2014 to 2017 were screened for azole resistance. Samples were subcultured in azole-containing agar plates. Isolates with a positive screening test were subject to DNA extraction, DNA amplification and sequencing of the cyp51A gene (coding and promoter regions). Clinical data were obtained from medical records. RESULTS: We screened 43 Aspergillus isolates from 39 patients for azole resistance. Three isolates from three patients grew on azole-containing agar plates: two A. fumigatus and one Aspergillus flavus. PCR analysis and cyp51A sequencing identified the TR34/L98H mutation in both A. fumigatus isolates. The prevalence of cyp51A mutations among A. fumigatus was 8.3% (2/24). Both patients with TR34/L98H mutants were azole naive and presented with invasive aspergillosis; one had multiple myeloma and the other was a liver retransplant recipient. They suffered progressive disease and failed voriconazole therapy. CONCLUSIONS: To the best of our knowledge, this is the first report of azole-resistant A. fumigatus with the TR34/L98H mutation in two azole-naive patients with refractory invasive aspergillosis in Mexico.
BACKGROUND: Fungicide exposure in the environment has driven the emergence of azole-resistant Aspergillus fumigatus worldwide. A screening test allows identification of resistant isolates. OBJECTIVES: We screened clinical samples for azole-resistant Aspergillus through azole-containing agar plates and identified mutations in the cyp51A gene of A. fumigatus. METHODS:Aspergillus isolates from clinical samples collected in a tertiary care centre from 2014 to 2017 were screened for azole resistance. Samples were subcultured in azole-containing agar plates. Isolates with a positive screening test were subject to DNA extraction, DNA amplification and sequencing of the cyp51A gene (coding and promoter regions). Clinical data were obtained from medical records. RESULTS: We screened 43 Aspergillus isolates from 39 patients for azole resistance. Three isolates from three patients grew on azole-containing agar plates: two A. fumigatus and one Aspergillus flavus. PCR analysis and cyp51A sequencing identified the TR34/L98H mutation in both A. fumigatus isolates. The prevalence of cyp51A mutations among A. fumigatus was 8.3% (2/24). Both patients with TR34/L98H mutants were azole naive and presented with invasive aspergillosis; one had multiple myeloma and the other was a liver retransplant recipient. They suffered progressive disease and failed voriconazole therapy. CONCLUSIONS: To the best of our knowledge, this is the first report of azole-resistant A. fumigatus with the TR34/L98H mutation in two azole-naive patients with refractory invasive aspergillosis in Mexico.
Authors: A Arastehfar; A Carvalho; J Houbraken; L Lombardi; R Garcia-Rubio; J D Jenks; O Rivero-Menendez; R Aljohani; I D Jacobsen; J Berman; N Osherov; M T Hedayati; M Ilkit; D James-Armstrong; T Gabaldón; J Meletiadis; M Kostrzewa; W Pan; C Lass-Flörl; D S Perlin; M Hoenigl Journal: Stud Mycol Date: 2021-05-10 Impact factor: 16.097