Invasive Fungal Disease, Isavuconazole Treatment Failure, and Death in Acute Myeloid Leukemia Patients

: We present 2 fatal cases of invasive fungal disease with isavuconazole treatment failure in immunocompromised patients: one with a TR34-L98H azole-resistant Aspergillus fumigatus isolate and the other a Rhizomucor-A. fumigatus co-infection. Such patients probably require surveillance by galactomannan antigen detection and quantitative PCRs for A. fumigatus and Mucorales fungi.