Febrile neutropenia (FN) is a complication of hematologic malignancy therapy. An early diagnosis would allow optimization of antimicrobials. The ¹⁸F-FDG-PET-CT may be useful; however, its role is not well established. We analyzed retrospectively patients with hematological malignancies who underwent ¹⁸F-FDG-PET-CT as part of FN management in our university hospital and compared with conventional imaging. In addition, we performed a systematic review of the literature assessing the usefulness of ¹⁸F-FDG-PET-CT in FN. A total of 24 cases of FN underwent ¹⁸F-FDG-PET-CT. In addition, 92% had conventional CT. In 5/24 episodes (21%), the fever was of infectious etiology: two were bacterial, two were fungal, and one was parasitic. When compared with conventional imaging, ¹⁸F-FDG-PET-CT had an added value in 20 cases (83%): it diagnosed a new site of infection in 4 patients (17%), excluded infection in 16 (67%), and helped modify antimicrobials in 16 (67%). Antimicrobials could be discontinued in 10 (41.6%). We identified seven publications of low quality and one randomized trial. Our results support those of the literature. The available data suggest that ¹⁸F-FDG-PET-CT is useful in the management of FN, especially to diagnose fungal infections and rationalize antimicrobials. This review points out the low level of evidence and indicates the gaps in knowledge.

Ruxolitinib is a JAK1 and JAK2 inhibitor approved in 2011 for the treatment of myelofibrosis., It is unclear if this drug can increase the risk of fungal infections. We present the case of a 67-year-old man with post-polycythemia vera myelofibrosis under treatment with ruxolitinib and azacitidine admitted to the Hematology Department with a history of subacute constitutional syndrome and diarrhea followed by fever. Biopsies of oral and colonic ulcerated lesions revealed Histoplasma; and subsequent bronchoalveolar lavage (BAL) was also positive for Histoplasma and Pneumocystis. Treatment with amphotericin B and isavuconazole was initiated without discontinuing ruxolitinib, resulting in a favourable response, confirmed by PET/CT. This case highlights the potential association of invasive fungal infection (IFI) with ruxolitinib treatment, the risk of endemic opportunistic fungal infections and the usefulness of PET/CT for follow-up of disseminated IFI.