RESUMEN
Aspergillus fumigatus resistant to azole as first-line therapy has been reported in azole-naïve patients. This worldwide resistance phenomenon has been linked to fungicide-driven alterations in the cyp51A gene and its promoter region (such as TR34/L98H and TR46/Y121F/T289A). Azole-resistant A. fumigatus related to the use of triazole fungicides in flower fields was recently reported In Colombia. The purpose of this study was to investigate the presence of azole-resistant A. fumigatus in soil samples from vegetable crops such as carrots, potatoes, maize, strawberries, and pea, and from prepared farming land surrounding the city of Bogotá. Species identification was based on sequencing of the ß-tubulin and calmodulin genes. All A. fumigatus strains were screened for azole resistance on agar supplemented with itraconazole or voriconazole. Among the 60 soil samples, 34 (56.6%) were positive for A. fumigatus and 15 samples exhibited strains (n = 18) that grew on agar supplemented with itraconazole or voriconazole. Triazole-resistant strains were isolated from soil samples associated with carrot, potato, maize, and pea crops. Sequencing of the cyp51A gene and its promoter region indicated polymorphism, mainly with the presence of TR46/Y121F/T289A (n = 8), TR34/L98H, and TR53. Eight resistant isolates exhibited cyp51A wild type without alterations in the promoter region. Our study showed evidence of dissemination of azole-resistant A. fumigatus, with high genetic diversity, in vegetable crops in Colombia. These data underline the need to determine the prevalence of azole resistance in A. fumigatus in clinical and environmental settings for other regions of Colombia as well as Latin America.
Asunto(s)
Aspergillus fumigatus/efectos de los fármacos , Azoles/administración & dosificación , Sistema Enzimático del Citocromo P-450/genética , Farmacorresistencia Fúngica , Proteínas Fúngicas/genética , Fungicidas Industriales/administración & dosificación , Enfermedades de las Plantas/prevención & control , Verduras/microbiología , Aspergillus fumigatus/clasificación , Aspergillus fumigatus/crecimiento & desarrollo , Aspergillus fumigatus/aislamiento & purificación , Azoles/farmacología , Calmodulina/genética , Colombia , Fungicidas Industriales/farmacología , Humanos , Polimorfismo Genético , Regiones Promotoras Genéticas , Análisis de Secuencia de ADN , Microbiología del Suelo , Tubulina (Proteína)/genéticaRESUMEN
A case of fatal aspergillosis due to a TR46/Y121F/T289A azole-resistant Aspergillus fumigatus is reported. Environmental investigations at the patient's residence led to the recovery of TR46/Y121F/T289A isolates, genotypically indistinguishable from the clinical isolate, supporting for the first time the direct role of household as potential source of azole-resistant invasive aspergillosis.