[Prophylactic strategies for invasive fungal infections after allogeneic hematopoietic stem cell transplantation].

Invasive fungal infections (IFIs) are one of the most serious complications developing after allogeneic hematopoietic stem cell transplantation (allo-HSCT). They are difficult to treat once present and usually have a fatal course in profoundly immunosuppressed patients. Upfront prevention therefore plays an important role in overcoming this threat. The combination of a protected environment and antifungal prophylaxis against Candida spp. is conventionally applied to prevent IFIs during the neutropenic period after HSCT, whereas mold-active agents are recommended for prophylaxis against Aspergillus spp. in the later period when high-dose steroids are frequently used for the treatment of graft-versus-host disease (GVHD). However, advances in transplantation technology have made the risk of IFIs more diverse and complex. Preventive strategies should be planned using the patient's background and surrounding environment as a guide for accurate evaluation of individual risks, and should also be revised to fit time-dependent changes in the patient's immune status and condition after HSCT. Sufficient knowledge of the properties of antifungal agents is also essential for maintaining the balance between the efficacy and the toxicity of the prophylaxis over time.