Antifungal prophylaxis in hematopoietic stem cell transplant recipients: the unfinished tale of imperfect success.

Antifungal prophylaxis in hematopoietic stem cell transplant recipients is a rapidly evolving field. For this prophylaxis to be beneficial and cost-effective, the risk of a life-threatening invasive fungal infection (IFI) should outweigh the risks of toxic effects and drug interactions introduced by the antifungal agent used. Not all hematopoietic stem cell transplant recipients have the same risk of IFIs. New prophylactic strategies using risk stratification and new broad-spectrum antifungals have the potential for reducing IFI-associated mortality in these patients. Further refinement of risk stratification and risk/benefit analysis (including pharmacoeconomic analysis) is needed. Stratification of IFI risk could be further sharpened based on emerging genetic and metabolic risk factors. However, 10 years after deciphering the human genome, it is unclear whether the genomic revolution would pay off for identifying the SCT recipients at highest risk for IFIs. Empiricism and reliance on institution-specific epidemiologic data are still expected to be a major part of the 'art and science' of risk stratification for fungal infections in SCT.