PERFIL CLÍNICO DE FUNGEMIA EM PACIENTES COM NEOPLASIAS HEMATOLÓGICAS EM UM HOSPITAL DE REFERÊNCIA DE SÃO LUÍS – MA, NOS ANOS DE 2022 A 2024

Abstract

In recent years, invasive fungal infections (IFIs) have become an important cause of morbidity and mortality in patients with hematologic malignancies. The difficulty of early diagnosis, combined with emerging antifungal resistance and variability among etiological agents—such as non-albicans Candida and emerging species—worsens the clinical scenario. Factors such as prolonged antifungal exposure, neutropenia, and intensive care unit admission increase the risk of unfavorable outcomes. In this context, the present study aimed to evaluate the clinical aspects of fungemia in patients with hematologic malignancies treated at a referral hospital in São Luís, Maranhão, Brazil, between 2022 and 2024. This retrospective study assessed 89 episodes of fungemia, including clinical variables, risk factors, isolated species, antifungal susceptibility profiles, and outcomes. Additionally, a cluster involving 14 Candida vulturna bloodstream isolates identified over a four-month period in 2022 was analyzed. Initial identification was performed using MALDI-TOF mass spectrometry, followed by confirmation through ITS sequencing and whole-genome sequencing. Antifungal susceptibility testing was conducted using microdilution and Sensititre YeastOne. The study population showed a pediatric predominance (median age 8.5 years), with acute lymphoblastic leukemia as the most frequent underlying malignancy. Risk factors were widely present, including central venous catheter use (92.6%), prior exposure to antibiotics (85.4%), and therapy-induced immunosuppression (58.4%). Candida parapsilosis (32.6%) and Candida tropicalis (19.1%) were the most prevalent species, while emerging yeasts such as C. vulturna, C. duobushaemulonii, and C. haemulonii were also identified. Most isolates demonstrated susceptibility to antifungal agents, although fluconazole resistance was observed in some C. parapsilosis strains, and high MIC values were noted in emerging species. Overall mortality was 48.3%, although deaths were not directly attributed to fungemia. During the C. vulturna outbreak, phenotypic methods misidentified isolates as other species within the C. haemulonii complex, necessitating molecular and genomic confirmation. Wholegenome sequencing analyses demonstrated clonality among the 14 isolates, confirming a hospital outbreak. All isolates exhibited low MICs and favorable clinical outcomes. Fungemia in patients with hematologic malignancies in Maranhão exhibits distinct epidemiological characteristics, with a predominance of non-albicans species and a significant occurrence of emerging yeasts, underscoring the need for continuous surveillance. The C. vulturna outbreak highlights the importance of incorporating molecular and genomic tools into routine diagnostics, as conventional methods may fail to correctly identify these yeasts. The findings contribute to the regional understanding of fungemia and reinforce the need for preventive strategies, rational antimicrobial use, strict management of invasive devices, and advanced identification methods to improve clinical outcomes in highly vulnerable populations.