Epidemiological shifts of invasive fungal infections in the current era of haematology

We aim to describe the epidemiology and risk factors for invasive fungal infections (IFI) and invasive mould infections (IMI) in hospitalized hematologic patients within the context of current hematologic therapies. Retrospective observational cohort study conducted on consecutive hematologic patients admitted to a tertiary hospital (2020-2023). Two populations were analysed: the full cohort of hospitalized patients (FC) and the subset of patients for whom mycological testing was specifically requested to rule out an IFI (SC). Proven or probable IFI was classified using European Organization for Research and Treatment of Cancer criteria. Risk factors for IFI and IMI were identified. A total of 1975 patients were included in the FC, whereas 1154 were included in the SC. IFI was diagnosed in 64 patients (65 episodes), and IMI in 43 patients (44 episodes). Aspergillosis was the most common IFI (58.4%), followed by candidemia (18.5%), Pneumocystis jirovecii pneumonia (PJP) (15.4%), mucormycosis (6.2%), and fusariosis (4.6%). Independent risk factors for IFI in the FC included acute leukemia (aOR 2.40, 95% CI 1.37-4.10, P = .002), corticosteroid use (aOR 2.36, 95% CI 1.40-4.03, P = .001) and graft versus host disease (GVHD) (aOR 2.13, 95% CI 0.93-4.46, P = .05). For IMI, risk factors were acute leukemia (aOR 2.71, 95% CI 1.33-5.52, P = .006), corticosteroid use (aOR 1.96, 95% CI 0.98-4.03, P = .05) and chronic lung disease (aOR 2.25, 95% CI 1.06-4.5, P = .02). In the SC, corticosteroid use (aOR 2.45, 95% CI 1.44-4.25, P = .001) was the independent risk factor for IFI, and corticosteroid use (aOR 2.40, 95% CI 1.21-4.91, P = .01) and GVHD (aOR 2.95, 95% CI 1.23-6.52, P = .009) were independent factors associated with IMI. Mortality was significantly higher in IFI patients compared to non-IFI patients (51.6% vs. 20.3%, P < .001). In this new era of haematology, the epidemiology of IFI is shifting, with Pneumocystis, Mucorales, and Fusarium becoming more prevalent. While corticosteroids and GVHD remain key risk factors, factors such as chronic lung disease are increasing its importance. Prolonged neutropenia may have decreased in relevance, likely due to prophylaxis. Preventing PJP has become a new challenge in IFI management.