Fusariosis in Immunocompromised Pediatric Patients: Results of a Monocentric Study

Over the past two decades, the incidence of rare invasive mycoses, including fusariosis, has increased. Fusariosis remains diagnostically challenging and is associated with high mortality. We conducted a retrospective-prospective monocentric study (01.01.2013 -01.11.2025) at the D. Rogachev National Medical Research Center for Pediatric Hematology, Oncology and Immunology to evaluate the clinical characteristics, diagnostic performance, and treatment outcomes of fusariosis in immunocompromised children. Sixteen patients (10 males, 6 females; median age 11.5 years, range 2.5–16) were included. Hematological malignancies were present in 70% cases; primary immunodeficiency, aplastic anemia, osteosarcoma, and systemic lupus erythematosus were less common. Fusariosis developed following chemotherapy (n=9), HSCT (n=4), or immunosuppressive therapy (n=3). Major risk factors included severe neutropenia and corticosteroid use (87.5%). Disseminated disease occurred 50% of patients, localized - in 40%, and isolated fungemia in one case. The most frequently affected sites were skin/soft tissues (50%), paranasal sinuses (50%), and lungs (43.75%). Parenchymal organs, bones and eyes involved less often. The predominant pathogens were Fusarium solani (n=6) and Fusarium proliferatum (n=5), followed by F. oxysporum, F. verticilioides, and F. petroliphilum. Invasive fungal co-infections (n=7) with Aspergillus flavus, Rhizopus spp., Scedosporium aurantiacum and Candida glabrata were associated with increased mortality. First–line therapy included lipid formulations of amphotericin B (81%) and voriconazole (56%), with combination therapy used in 62.5%. Fourteen patients achieved a rapid partial response (median 21 days), which correlated with favorable outcomes: all these patients were cured, with significantly higher overall survival. In the entire cohort 6-week survival was 81%, overall survival was 69%. The study demonstrated that early diagnostic and targeted therapy significantly improve outcomes in immunocompromised children with invasive fusariosis.