RESUMO
Invasive candidosis is the most common invasive fungal infection in hospitalized patients and is associated with a high mortality rate. This is the first study from a Croatian tertiary care hospital describing epidemiology, risk factors and species distribution in patients with candidemia. A three-year retrospective observational study, from 2018 to 2020, was performed at the University Hospital Centre Zagreb, Zagreb, Croatia. A total of 160 patients with candidemia (n = 170 isolates) were enrolled. Candidemia incidence increased from 0.47 to 0.69 per 1000 admissions in 2018 and 2020, respectively. Ninety-five patients (58.38%) were in the intensive care unit. The main risk factors for candidemia were central venous catheter (CVC) (84.38%), previous surgical procedure (56.88%) and invasive mechanical ventilation (42.50%). Candida albicans was identified in 43.53% of isolates, followed by C. parapsilosis (31.76%) and C. glabrata (12.36%), C. krusei (5.29%), C. tropicalis (2.35%) and C. lusitaniae (2.35%). The study discovered a shift to non-albicansCandida species, particularly C. parapsilosis, and made it possible to determine the main tasks we should focus on to prevent candidemia in the hospital, these being mainly infection control measures directed towards prevention of catheter-related bloodstream infections, specifically comprising hand hygiene and CVC bundles of care. The potential benefit of fluconazole prophylaxis in certain populations of surgical patients could also be considered.
RESUMO
Gliotoxin is a secondary metabolite of the epipolythiodioxopiperazine family with biologically active internal disulfide bridge. It is produced by many fungal species, including Aspergillus fumigatus and A. terreus. A. fumigatus, which produces gliotoxin and more than twenty other secondary metabolites, is the leading cause of invasive aspergillosis. Gliotoxin production in situ influence the development of aspergillosis. This study investigated the in vitro production of gliotoxin in nine A. fumigatus isolates from the upper respiratory tract of immunocompromised patients. The effects of media composition and incubation temperature were studied. Gliotoxin was extracted from biomass and its concentration was semi-quantitatively analysed using thin-layer chromatography. Gliotoxin production was higher in the yeast-extract liquid medium (YES) than in the synthetic Czapek-Dox liquid medium (CZA). Incubation at 37 degrees C resulted in higher gliotoxin production than at 25 degrees C, probably because higher temperatures favour expansive growth of the mycelium. Gliotoxin could be detected after three days of incubation at concentrations 4.06 mg mL(-1) (in YES at 37 degrees C) and 1.07 mg mL(-1) (in CZA at 25 degrees C). YES broth as a medium containing 4% sucrose and 2% of yeast extract is a very rich substrate for the production of gliotoxin in vitro.
Assuntos
Aspergillus fumigatus/metabolismo , Gliotoxina/biossíntese , Meios de Cultura , TemperaturaRESUMO
AIM: The incidence, outcome and risk factors for developing invasive fungal infection were retrospectively analyzed in 150 patients with acute leukemia during intensive cytostatic therapy. PATIENTS AND METHODS: Patients with and without the diagnosis of fungal infection were compared according to age, sex, diagnosis, stage of disease, type of therapy, antimicrobial prophylaxis, duration of febrile episodes, duration of antimicrobial therapy, duration of antifungal therapy, chest x-ray findings, results of surveillance cultures for fungal species isolation, clinical diagnosis at discharge from hospital, and autopsy findings. Clinical findings in patients with confirmed fungal infection on autopsy were analyzed separately. RESULTS: The incidence of fungal infection according to clinical diagnosis was 38.5%. The incidence among patients who died during therapy at autopsy was 78.5%. The incidence of Candida and Aspergillus infections at autopsy was 40% and 60%, respectively. Specific incidence could not be determined during life. The mortality was 59% in the group of patients with fungal infection, and 43% in the group of patients without fungal infection. During the study, an increase in the rate of fungal infection as well as a trend to prolonged survival of these patients were observed. On multivariate analysis, independent risk factors associated with a greater incidence of fungal infection were duration of hospitalization (p=0.04), duration of granulocytopenia with granulocyte count less than 0.5x10(9)/L (p=0.05), number of febrile episodes (p=0.01), duration of febrile episode (p=0.001), intestinal decontamination (p=0.02), duration of antibiotic therapy (p=0.01), positive chest x-ray finding (p=0.001), and year of therapy (p=0.02). On univariate analysis, a greater incidence of fungal infections was also associated with younger age, acute lymphatic leukemia, newly diagnosed disease and second relapse of the disease. The occurrence of fungal infections showed no correlation with the type of therapy, number of chemotherapy cycles, type of fungal species isolated from particular locations and frequency of colonization at particular locations. However, the number of colonized locations and number of fungal species was two to three times greater in patients with than in those without fungal infection. CONCLUSIONS: Fungal infections are becoming an increasing problem during intensive therapy of acute leukemia and contribute to poor therapy outcome. The diagnosis of fungal infection during life is extremely difficult and frequently late. There is the need of a more precise diagnostic test that would provide earlier diagnosis. The knowledge of risk factors is helpful in the diagnosis and therapy of fungal infections. The suspicion of fungal infection in patients at risk justifies the introduction of antifungal therapy and contributes to better therapeutic outcome.
