Azole-resistant Aspergillus fumigatus in the environment of Northern Italy, May 2011 to June 2012

In recent years acquired azole resistance in Aspergillus fumigatus has been increasingly reported and a dominant mechanism of resistance (TR34/L98H) was found in clinical and environmental isolates.The aim of the present study was to investigate the prevalence of azole resistance in environmental A. fumigatus isolates collected in Northern Italy. A. fumigatus grew from 29 out of 47 soil samples analysed. Azole resistant isolates were detected in 12.7% of the soil samples and in 20.7% of the soil samples containing A. fumigatus. High minimal inhibitory concentrations of itraconazole, posaconazole and voriconazole were displayed by nine isolates from six different soil samples, namely apple orchard (1 sample), rose pot compost (2 samples), and cucurbit yields (3 samples). Seven out of nine resistant isolates harboured the same TR34/L98H mutation of cyp51A. These findings, together with the occurrence of resistant clinical isolates, suggest that azole resistance should be considered in primary patient care. suggest that azole resistance should be considered in primary patient care.