DANILO YAMAMOTO THOMAZ
Projetos de Pesquisa
Unidades Organizacionais
FM, Faculdade de Medicina - Docente
LIM/53 - Laboratório de Micologia, Hospital das Clínicas, Faculdade de Medicina
LIM/53 - Laboratório de Micologia, Hospital das Clínicas, Faculdade de Medicina
15 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 15
- Candida blankii: an emergent opportunistic yeast with reduced susceptibility to antifungals(2018) ALMEIDA JR., Joao Nobrega de; CAMPOS, Silvia V.; THOMAZ, Danilo Y.; THOMAZ, Luciana; ALMEIDA, Renato K. G. de; NEGRO, Gilda M. B. del; GIMENES, Viviane F.; GRENFELL, Rafaella C.; MOTTA, Adriana L.; ROSSI, Flavia; BENARD, Gil
- Identification and antifungal susceptibility of Candida species isolated from the urine of patients in a university hospital in Brazil(2017) LIMA, Glaucia Moreira Espindola; NUNES, Maina de Oliveira; CHANG, Marilene Rodrigues; TSUJISAKI, Rosianne Assis de Sousa; NUNES, Joslaine de Oliveira; TAIRA, Cleison Ledesma; THOMAZ, Danilo Yamamoto; NEGRO, Gilda Maria Barbaro Del; MENDES, Rinaldo Poncio; PANIAGO, Anamaria Mello MirandaThe aim of this study was to identify Candida spp. isolated from candiduria episodes at a tertiary hospital in the Midwest region of Brazil, and to determine their susceptibility profiles to antifungal compounds. From May 2011 to April 2012, Candida spp. isolated from 106 adult patients with candiduria admitted to the University Hospital of the Federal University of Mato Grosso do Sul were evaluated. Both, species identification and susceptibility testing with fluconazole-FLC, voriconazole-VRC, and amphotericin B-AmB were carried out using the Vitek 2. To discriminate species of the C. parapsilosis complex, a RAPD-PCR technique using the RPO2 primer was performed. From the total of 106 isolates, 42 (39.6%) C. albicans and 64 (60.4%) Candida non-albicans (CNA) -33 C. tropicalis, 18 C. glabrata, 5 C. krusei, 4 C. parapsilosis sensu stricto, 2 C. kefyr, 1 C. lusitaniae, and 1 C. guilliermondii were identified. All isolates were susceptible to AmB and VRC, whereas all C. glabrata isolates presented either resistance (5.6%) or dose-dependent susceptibility (94.4%) to FLC. The study of Candida spp. and their resistance profiles may help in tailoring more efficient therapeutic strategies for candiduria.
- Lomentospora prolificans fungemia in hematopoietic stem cell transplant patients: First report in South America and literature review(2018) PENTEADO, Fernando D.; LITVINOV, Nadia; SZTAJNBOK, Jaques; THOMAZ, Danilo Y.; SANTOS, Antonio M. dos; VASCONCELOS, Dewton M.; MOTTA, Adriana L.; ROSSI, Flavia; FERNANDES, Juliana F.; MARQUES, Heloisa Helena S.; BENARD, Gil; ALMEIDA JR., Joao N. deLomentospora prolificans is a filamentous fungus and an emerging pathogen in immunocompromised patients. It is encountered most commonly in Australia, Spain, and USA. We described the first case of Lomentospora prolificans fungemia in South America. The patient was a hematopoietic stem cell transplantation (HSCT) recipient who developed the infection 37days after stem cells infusion. In addition, we performed a literature review of invasive lomentosporiosis in HSCT patients.
- Candida haemulonii Complex Species, Brazil, January 2010-March 2015(2016) ALMEIDA JR., Joao Nobrega de; ASSY, Joao Guilherme Pontes Lima; LEVIN, Anna S.; NEGRO, Gilda M. B. Del; GIUDICE, Mauro C.; TRINGONI, Marcela Pullice; THOMAZ, Danilo Yamamoto; MOTTA, Adriana Lopes; ABDALA, Edson; PIERROTI, Ligia Camara; STRABELLI, Tania; MUNHOZ, Ana Lucia; ROSSI, Flavia; BENARD, Gil
- An Azole-Resistant Candida parapsilosis Outbreak: Clonal Persistence in the Intensive Care Unit of a Brazilian Teaching Hospital(2018) THOMAZ, Danilo Yamamoto; ALMEIDA JR., Joao Nobrega de; LIMA, Glaucia Moreira Espindola; NUNES, Maina de Oliveira; CAMARGO, Carlos Henrique; GRENFELL, Rafaella de Carvalho; BENARD, Gil; NEGRO, Gilda M. B. DelThe incidence of candidemia by the Candida parapsilosis complex has increased considerably in recent decades, frequently related to use of indwelling intravascular catheters. The ability of this pathogen to colonize healthcare workers (HCW)' hands, and to form biofilm on medical devices has been associated with the occurrence of nosocomial outbreaks and high mortality rates. Fluconazole has been the leading antifungal drug for the treatment of invasive candidiasis in developing countries. However, azole-resistant C. parapsilosis isolates are emerging worldwide, including in Brazil. Few studies have correlated outbreak infections due to C. parapsilosis with virulence factors, such as biofilm production. We thus conducted a microbiological investigation of C. parapsilosis complex isolates from a Brazilian teaching hospital. Additionally, we identified a previously unrecognized outbreak caused by a persistent azole-resistant C. parapsilosis (sensu stricto) clone in the intensive care unit (ICU), correlating it with the main clinical data from the patients with invasive candidiasis. The molecular identification of the isolates was carried out by PCR-RFLP assay; antifungal susceptibility and biofilm formation were also evaluated. The genotyping of all C. parapsilosis (sensu stricto) was performed by microsatellite analysis and the presence of ERG11 mutations was assessed in the azole non-susceptible isolates. Fourteen C. parapsilosis (sensu stricto) isolates were recovered from patients with invasive candidiasis, eight being fluconazole and voriconazole-resistant, and two intermediate only to fluconazole (FLC). All non-susceptible isolates showed a similar pattern of biofilm formation with low biomass and metabolic activity. The A395T mutation in ERG11 was detected exclusively among the azole-resistant isolates. According to the microsatellite analysis, all azole non-susceptible isolates from the adult ICU were clustered together indicating the occurrence of an outbreak. Regarding clinical data, all patients infected by the clonal non-susceptible isolates and none of the patients infected by the susceptible isolates had been previously exposed to corticosteroids (p=0.001), while the remaining characteristics showed no statistical significance. The current study revealed the persistence of an azole non-susceptible C. parapsilosis clone with low capacity to form biofilm over two years in the adult ICU. These results reinforce the need of epidemiological surveillance and monitoring antifungal susceptibility of C. parapsilosis isolates in hospital wards.
conferenceObject Candida parapsilosis clinical isolates resistant and susceptible to azoles with identical genetic profile determined by PFGE-RFLP(2015) THOMAZ, D. Y.; GIUDICE, M. C.; GAUDERETO, J. J.; GRENFELL, R. C.; LIMA, G. M. E.; NUNES, M. O.; FIGUEIREDO, D. S. Y.; NEGRO, G. M. B. del- A Brazilian Inter-Hospital Candidemia Outbreak Caused by Fluconazole-Resistant Candida parapsilosis in the COVID-19 Era(2022) THOMAZ, Danilo Y.; NEGRO, Gilda M. B. Del; RIBEIRO, Leidiane B.; SILVA, Mirian da; CARVALHO, Gabrielle O. M. H.; CAMARGO, Carlos H.; ALMEIDA, Joao N. de; MOTTA, Adriana L.; SICILIANO, Rinaldo F.; SEJAS, Odeli N. E.; ROSSI, Flavia; ABDALA, Edson; STRABELLI, Tania M. V.; BENARD, GilHorizontal transmission of fluconazole-resistant Candida parapsilosis (FRCP) through healthcare workers' hands has contributed to the occurrence of candidemia outbreaks worldwide. Since the first COVID-19 case in Brazil was detected in early 2020, hospitals have reinforced hand hygiene and disinfection practices to minimize SARS-CoV-2 contamination. However, a Brazilian cardiology center, which shares ICU patients with a cancer center under a FRCP outbreak since 2019, reported an increased FRCP candidemia incidence in May 2020. Therefore, the purpose of this study was to investigate an inter-hospital candidemia outbreak caused by FRCP isolates during the first year of the COVID-19 pandemic in Brazil. C. parapsilosis bloodstream isolates obtained from the cancer (n = 35) and cardiology (n = 30) centers in 2020 were submitted to microsatellite genotyping and fluconazole susceptibility testing. The ERG11 gene of all isolates from the cardiology center was sequenced and compared to the corresponding sequences of the FRCP genotype responsible for the cancer center outbreak in 2019. Unprecedentedly, most of the FRCP isolates from the cardiology center presented the same genetic profile and Erg11-Y132F mutation detected in the strain that has been causing the persistent outbreak in the cancer center, highlighting the uninterrupted horizontal transmission of clonal isolates in our hospitals during the COVID-19 pandemic.
- Determinants of fluconazole resistance and echinocandin tolerance in C. parapsilosis isolates causing a large clonal candidemia outbreak among COVID-19 patients in a Brazilian ICU(2022) DANESHNIA, Farnaz; ALMEIDA JUNIOR, Joao N. de; ARASTEHFAR, Amir; LOMBARDI, Lisa; SHOR, Erika; MORENO, Lis; MENDES, Ana Verena; BARBERINO, Maria Goreth; YAMAMOTO, Danilo Thomaz; BUTLER, Geraldine; PERLIN, David S.; COLOMBO, Arnaldo LopesPatients presenting with severe COVID-19 are predisposed to acquire secondary fungal infections such as COVID-19-associated candidemia (CAC), which are associated with poor clinical outcomes despite antifungal treatment. The extreme burden imposed on clinical facilities during the COVID-19 pandemic has provided a permissive environment for the emergence of clonal outbreaks of multiple Candida species, including C. auris and C. parapsilosis. Here we report the largest clonal CAC outbreak to date caused by fluconazole resistant (FLZR) and echinocandin tolerant (ECT) C. parapsilosis. Sixty C. parapsilosis strains were obtained from 57 patients at a tertiary care hospital in Brazil, 90% of them were FLZR and ECT. Although only 35.8% of FLZR isolates contained an ERG11 mutation, all of them contained the TAC1(L518F) mutation and significantly overexpressed CDR1. Introduction of TAC1(L518F) into a susceptible background increased the MIC of fluconazole and voriconazole 8-fold and resulted in significant basal overexpression of CDR1. Additionally, FLZR isolates exclusively harboured E1939G outside of Fks1 hotspot-2, which did not confer echinocandin resistance, but significantly increased ECT. Multilocus microsatellite typing showed that 51/60 (85%) of the FLZR isolates belonged to the same cluster, while the susceptible isolates each represented a distinct lineage. Finally, biofilm production in FLZR isolates was significantly lower than in susceptible counterparts Suggesting that it may not be an outbreak determinant. In summary, we show that TAC1(L518F) and FKS1(E1393G) confer FLZR and ECT, respectively, in CAC-associated C. parapsilosis. Our study underscores the importance of antifungal stewardship and effective infection control strategies to mitigate clonal C. parapsilosis outbreaks.
conferenceObject Variation in the polysaccharide capsule size interferes with identification of Cryptococcus neoformans and C. gattii by MALDI-TOF mass spectrometry(2015) THOMAZ, D. Y.; VIDAL, M. S. M.; GRENFELL, R. C.; GIUDICE, M. C.; JULIANO NETO, L.; BENARD, G.; NEGRO, G. M. B. del; ALMEIDA JR., J. N.- In vitro activity of sanitizers against mono- and polymicrobial biofilms of C. parapsilosis and S. aureus(2023) CASTRO, Vitor de Paula; THOMAZ, Danilo Yamamoto; VIEIRA, Kayro de Lima; LOPES, Leonardo Guedes; ROSSI, Flavia; NEGRO, Gilda M. B. Del; BENARD, Gil; PIRES, Regina HelenaThe emergence of disinfectant-resistant microorganisms poses a significant threat to public health. These resilient pathogens can survive and thrive in hospital settings despite routine disinfection practices, leading to persistent infections and the potential for outbreaks. In this study, we investigated the impact of 11 different commercial sanitizers at various concentrations and exposure times on biofilms consisting of clinical and nosocomial environmental isolates of Candida parapsilosis and Staphylococcus aureus. Among the sanitizers tested, 0.5% and 2.0% chlorhexidine (CLX), 10% polyvinyl pyrrolidone (PVP-I), a disinfectant based on quaternary ammonium compound (QAC), 2% glutaraldehyde, and 0.55% orthophthalaldehyde (OPA) demonstrated efficacy against both C. parapsilosis and S. aureus in monospecies and mixed biofilms. Analysis showed that 0.5% CLX and 10% PVP-I had fungicidal and bactericidal activity against all biofilms. However, the sanitizer based on QAC and 0.55% OPA proved to be bacteriostatic and fungicidal against both monospecies and mixed biofilms. In mixed biofilms, despite the last four sanitizers exerting fungicidal action, the reduction of fungal cells was approximately 4 log(10) CFU/mL compared to monospecies biofilms, showing that the interaction provided more resistance of the yeast to the sanitizer. Formation of mixed biofilms in hospital settings can create an ecological niche that enhances the survival of pathogens against routine sanitization procedures. Therefore, effective sanitization practices, including regular cleaning with effective sanitizers, should be implemented to prevent C. parapsilosis/S. aureus biofilm formation in healthcare settings.