Distribution of filamentous fungi causing invasive fungal disease at the Haematological Unit, Hospital de Clínicas de Porto Alegre, Brazil

AbstractVery limited data are available in the literature to elucidate the aetiology of invasive mould infections in Latin America. Here we report that Aspergillus species caused only half of such cases in a cohort study conducted over 21 months in a university hospital in Porto Alegre, Southern Brazil. Fusarium spp. were the second most prevalent moulds (20.7%), followed by Zygomycetes (13.8%). The importance of obtaining local epidemiological data for adequately guiding empirical antifungal therapy is reinforced

Distribution of filamentous fungi causing invasive fungal disease at the Haematological Unit, Hospital de Clínicas de Porto Alegre, Brazil

AbstractVery limited data are available in the literature to elucidate the aetiology of invasive mould infections in Latin America. Here we report that Aspergillus species caused only half of such cases in a cohort study conducted over 21 months in a university hospital in Porto Alegre, Southern Brazil. Fusarium spp. were the second most prevalent moulds (20.7%), followed by Zygomycetes (13.8%). The importance of obtaining local epidemiological data for adequately guiding empirical antifungal therapy is reinforced

Epidemiological aspects and characterization of the resistance profile of Fusarium spp. in patients with invasive fusariosis

Introduction. The remarkable intrinsic resistance of Fusarium species to most antifungal agents results in high mortality rates in the immunocompromised population. Aims. This study aimed to investigate the epidemiology, clinical features and antifungal susceptibility of Fusarium isolates in patients with invasive fusariosis. Methodology. A total of 27 patients admitted to a referral hospital from January 2008 to June 2017 were evaluated. Antifungal susceptibility testing of isolates was performed by broth microdilution according to the Clinical and Laboratory Standards Institute guidelines. Results. Haematological malignancy was the predominant underlying condition, with an incidence of invasive fusariosis of 14.8 cases per 1000 patients with acute lymphoid leukaemia and 13.1 cases per 1000 patients with acute myeloid leukaemia. The Fusarium solani species complex (FSSC) was the most frequent agent group, followed by the Fusarium oxysporum species complex (FOSC). Voriconazole showed the best activity against Fusarium, followed by amphotericin B. Itraconazole showed high minimum inhibitory concentration values, indicating in vitro resistance. Clinical FSSC isolates were significantly (P<0.05) more resistant to amphotericin B and voriconazole than FOSC isolates. Conclusion. The present antifungal susceptibility profiles indicate a high incidence of fusariosis in patients with haematological malignancy. Species- and strain-specific differences in antifungal susceptibility exist within Fusarium in this setting

Variability in Galactomannan detection by platelia Aspergillus EIA™ according to the Aspergillus species

Here we investigate the extent to which different Aspergillus species release galactomannan (GM) in vitro. Marked variability was observed in GM reactivity between and within Aspergillus species, with A. terreus strains showing the highest GM indexes. The in vivo significance of these findings remains to be determined.O estudo objetivou investigar a liberação in vitro de galactomanana (GM) em distintas espécies patogênicas de fungos do gênero Aspergillus. Grande variabilidade foi detectada tanto intra quanto inter espécies, sendo as cepas da espécie A. terreus relacionadas aos maiores índices de GM detectados. O significado in vivo destes achados permanece em aberto, porém merece investigação

Evaluation of identification and susceptibility for Candida spp. isolated directly from positive blood culture bottles

Determination of the susceptibility profile of isolates of Candida from blood culture bottles is extremely important for correctly guiding patient pharmacotherapy. ,e aim of this study was to compare the results of analysis of Candida isolated directly from blood culture bottles by the VITEK MS MALDI-TOF identification system and the fluconazole disk diffusion assay with those of standard identification methods. Testing directly from the bottle allowed results 24 to 48 hours quicker than the standard method. ,ere was a categorical agreement of 51.64% (47 of 91 samples) between the results of analysis directly from the bottle and analysis by the standard method. Regarding species identification, there was 96.15% agreement for Candida parapsilosis (25 of 26 samples). Categorical agreement between the rapid and standard disk diffusion methods was 95%, and the agreement between the rapid disk diffusion method and the broth microdilution method was 97%. Only minor errors in the rapid method were observed: 3 (5%) in the standard disk diffusion method and 2 (3%) in the broth microdilution method. Our study concluded that the rapid disk diffusion method for fluconazole is a fast, easy, reproducible, and consistent method. Its timely implementation for testing antifungal agents in the clinical microbiology laboratory can help reduce profile release times, thus helping to determine the most appropriate antifungal treatment

Performance of polymyxin B Etest in a setting of high prevalence of KPC-producing Klebsiella pneumoniae

Objectives: Polymyxin resistance has been increasing in many regions, and appropriate determination ofpolymyxin susceptibility is now a major challenge worldwide. Many clinical laboratories rely on gradientdiffusion methods to assess polymyxin susceptibility, although broth microdilution (BMD) is the onlymethod currently recommended by the CLSI and EUCAST. The aim of this study was to assess theperformance of the polymyxin B (PMB) Etest in a setting with a high prevalence of KPC-producingKlebsiella pneumoniae (KPC-KP).Methods: A commercial Etest susceptibility testing method was evaluated and compared with thereference BMD method, considering isolates with a minimum inhibitory concentration (MIC) 2 mg/L forPMB as susceptible to this drug. A total of 310 clinical KPC-KP isolates were evaluated.Results: Susceptibility was significantly higher by Etest compared with BMD (82.6% vs. 75.8%). The MIC50,MIC90and modal MICs for PMB were 0.25, 32 and 0.25 mg/L (27.1%) by BMD and 0.5, 16 and 0.5 mg/L(49.7%) by Etest, respectively. Although categorical agreement was 90.0%, there was poor essentialagreement (50.6%). A high rate (34.7%) of very major errors (VMEs) and a relatively low rate (2.1%) ofmajor errors were found.Conclusion: The considerable number of resistant isolates in this study allowed an accurate estimation ofVME rates and, consequently, a more comprehensive assessment of susceptibility testing for polymyxins.Etest did not meet fully the acceptance criteria for US FDA requirements. These data do not support theuse of this commercial method for determining PMB MICs in carbapenem-resistant Enterobacterales populations