Background: The AsperGeniusVR assay is a multiplex real-time PCR test that allows the simultaneous detection of Aspergillus species and identification of the most common mutations in the Aspergillus fumigatus cyp51A gene conferring resistance (TR34/L98H and TR46/T289A/Y121F) by using melting curve analysis. Mixed infections with azole-resistant and susceptible A. fumigatus have rarely been described. Methods: The AsperGeniusVR multiplex real-time PCR assay (PathoNostics, Maastricht, the Netherlands) was used on bronchoalveolar lavage (BAL) samples of 91 consecutive patients with a suspected invasive Aspergillus infection at the Erasmus MC University Medical Center, Rotterdam. Results: In three cases the AsperGeniusVR assay indicated the simultaneous presence of WT and mutant genes (two patients with TR34/L98H mutation and one patient with TR46/T289A/Y121F mutation) and therefore mixed infections with azole-susceptible and -resistant isolates. In one of the three cases, the mixed infection was confirmed by phenotypic antifungal testing of multiple A. fumigatus colonies. Conclusions: The use of a dedicated A. fumigatus cyp51A resistance PCR allowed the detection of mixed infections with azole-resistant and -susceptible Aspergillus strains. These mixed infections may remain undiagnosed with conventional phenotypic susceptibility testing.,
Journal of Antimicrobial Chemotherapy
Department of Internal Medicine

Schauwvlieghe, A., Vonk, A., Buddingh, E., Hoek, R., Dalm, V., Klaassen, C.H.W. (C. H.W.), & Rijnders, B. (2017). Detection of azole-susceptible and azole-resistant Aspergillus coinfection by cyp51A PCR amplicon melting curve analysis. Journal of Antimicrobial Chemotherapy, 72(11), 3047–3050. doi:10.1093/jac/dkx262