High airborne level of Aspergillus fumigatus and presence of azole-resistant TR34/L98H isolates in the home of a cystic fibrosis patient harbouring chronic colonisation with azole-resistant H285Y A. fumigatus

Azole-resistant Aspergillus fumigatus (ARAF) has been reported in the domestic environment of patients at risk for aspergillosis. Here, we assessed the mother's and father's homes of an 18-year-old cystic fibrosis patient harbouring chronic colonisation with H285Y CYP51A azole-resistant isolate, in order to explore the link between environmental exposure and ARAF infection. In one dwelling, a very high overall contamination level was found (710–7.240 CFU/m3), with a predominance of A. fumigatus (640–6.490 CFU/m3), and ARAF showing the TR34/L98H mutation was isolated. Mycological follow-up of the patient showed the persistence of H285Y isolates, but no acquisition of TR34/L98H isolates was observed. This could be due to the low proportion of TR34/L98H isolates (