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.

Additional Metadata
Persistent URL dx.doi.org/10.1093/jac/dkx262, hdl.handle.net/1765/108502
Journal Journal of Antimicrobial Chemotherapy
Citation
Schauwvlieghe, A.F.A.D. (A. F.A.D.), Vonk, A.G, Buddingh, E.P. (E. P.), Hoek, R.A.S, Dalm, V.A.S.H, Klaassen, C.H.W. (C. H.W.), & Rijnders, B.J.A. (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