Invasive fungal infections in patients with acute leukemia: A retrospective cohort study at a tertiary-care hospital

Invasive fungal infection (IFI) is an important cause of morbidity and mortality in acute leukemia patients. In the past few decades, the incidence of IFI has dramatically increased. Nevertheless, the management of IFI has become more complicated owing to changes in the epidemiology of fungal diseases and therapeutic regimens. Therefore, it is important to establish an appropriate strategy for centers that provide the diagnosis and treatment of acute leukemia patients based on scientific data and with available resources. In this study we investigated the incidence of IFI, pathogens, the use of diagnostic methods, and risk factors for IFI in acute leukemia patients over a 17-year period. A total of 502 acute leukemia patients (male/female: 57%/43%, mean age: 57.7 ± 15.5 years) hospitalized at adult and oncology hospitals between 2003 and 2020 were reviewed retrospectively. The incidence of proven and probable IFI was 13.2% (33.1%, when possible cases were included). The most common IFI was aspergillosis (49 patients, 9.7%), followed by candidemia, mucormycosis, and Pneumocystis jirovecii pneumonia. The galactomannan antigen test was positive in the serum of 39 (23.5%) patients and in bronchoalveolar lavage (BAL) fluid in 6 (3.6%) patients. Thirteen (7.8%) sputum cultures (11 Aspergillus spp. and 2 Candida spp.) and 4 (2.4%) BAL fluid (1 Aspergillus spp., 2 Candida spp., 1 P jirovecii) were positive for a fungal pathogen. Neutropenia, intensive care unit (ICU) follow-up and mechanical ventilation (MV) increased the risk of IFI by 3.5, 2.5, and 1.8 times, respectively. The median survival was 5 (range: 1.9-8) months. ICU follow-up shortened the survival by 12 months and increased the death risk by 2.49-fold. MV shortened survival by 57 months and increased the death risk by 3.82-fold. IFI remains a significant contributor to the morbidity and mortality in acute leukemia patients. Pulmonary involvement is the most common site. Neutropenia, ICU follow-up and MV are associated with an increased risk for IFI and mortality. We recommend in the IFI approach, to be aware of IFI in patients receiving intensive chemotherapy and/or recipients of hematopoietic stem cell transplantation, and to evaluate with microbiological, serological and radiological tests during the clinical follow-up.