Selection of isolates carrying the G448S substitution in 51A gene after long-term treatment with voriconazole in an immunocompromised patient.

We present a case of a 55-year-old man with a heart transplant who acquired Invasive Aspergillosis by with the focus in the kidney. During about two years of antifungal treatment, most of the time with voriconazole, it was possible to obtain nine isolates of with the same genotypic characteristics, but with an increase in MIC for several azoles. The two last isolates presented high MICs for Voriconazole (>8 μg/mL>). Sequencing of the 51A gene showed G448S amino acid substitution in the same two isolates. In long-term treatments with antifungals, it would be important to regularly evaluate the susceptibility of isolated strains, as resistance to azoles has been increasingly described around the world.