Managing Breakthrough Fungal Infections in Hematologic Patients: Determinants and Practical Management from a Latin American Perspective on Behalf of INFOCUS LATAM-ISHAM Working Group.

Breakthrough invasive fungal infections (bIFIs) are a challenging serious complication in high-risk hematologic patients and allogeneic hematopoietic stem cell transplantation recipients that may negatively impact their outcome. Despite advances in antifungal prophylaxis, diagnostics, and supportive care, bIFI occurrence reflects a complex interaction between host immunosuppression, emergence of resistant pathogens and pharmacological variables, including subtherapeutic drug exposure. Candida spp. have shifted towards non-albicans yeasts, whereas breakthrough mold infections more frequently involve non-fumigatus Aspergillus, Mucorales, Fusarium spp., and Scedosporium/Lomentospora spp. Early clinical recognition, rapid therapy escalation, aggressive diagnostic investigation, a switch to liposomal amphotericin B-based regimens in patients on azole prophylaxis, and therapeutic drug monitoring are essential to improve outcomes. Reducing the growing global burden of bIFIs will also require improved access to high-quality diagnostics and strengthened educational and stewardship efforts that prioritize antifungal resistance as an urgent health concern.