Disseminated Fusarium infection following cladribine chemotherapy for hairy-cell leukaemia

Hairy cell leukaemia (HCL) is a B-cell malignancy whose induction chemotherapy consists of 5 days of cladribine, a purine nucleoside analogue. While there are consensus guidelines from the National Comprehensive Cancer Network (NCCN) on antifungal prophylaxis in the setting of acute myeloid leukaemia or acute lymphocytic leukaemia, there are no consensus guidelines for antifungal prophylaxis during induction treatment of HCL. We describe a case of angioinvasive Fusarium infection in a healthy, young patient who completed cladribine chemotherapy for HCL. While rare, fusariosis poses a significant morbidity and mortality risk in neutropenic patients undergoing treatment. Prevention of fusariosis requires appropriate prophylactic agents and treatment requires resolution of neutropenia and the elimination of the fungus. This case highlights early recognition and prompt start of antifungals as the cornerstone of management. Antifungal prophylaxis is not routinely recommended during HCL induction, and whether patients might benefit from prophylaxis warrants further study.