Primary antifungal prophylaxis in hematopoietic stem cell transplant recipients: clinical implications of recent studies.

PURPOSE OF REVIEW

Infectious complications after hematopoietic stem cell transplant, especially those caused by fungi, contribute to poor outcomes. Availability of new antifungal drugs has led to creative attempts to prevent infections caused by both yeasts and molds with new antifungal prophylaxis strategies; these studies will be reviewed.

RECENT FINDINGS

Trials evaluating mold-active azoles, posaconazole and voriconazole, demonstrate that invasive aspergillosis infections can be prevented by prophylactic therapy in patients with hematologic malignancies and after allogeneic hematopoietic stem cell transplant. However, issues arise regarding appropriate dosing and levels, drug interactions, and the importance of breakthrough infections caused by organisms that demonstrate microbiologic resistance. Other recent studies evaluating efficacy and safety of aerosolized lipid formulations of amphotericin B demonstrate promise with directed delivery to the lungs; more long-term follow-up safety information is needed to be assured that this strategy is safe late after allogeneic hematopoietic stem cell transplant, in the setting of acute and chronic graft vs. host disease.

SUMMARY

Clinicians should consider using new mold-active azole drugs for prophylaxis instead of fluconazole in allogeneic hematopoietic stem cell transplant recipients that have high risks due to prolonged neutropenia and severe graft vs. host disease. More investigations are needed to support other preventive strategies that utilize diagnostic tests and aerosolized delivery of amphotericin B formulations.