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
10 resultados
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- 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
- 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.
- 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.
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.- Lack of efficacy of echinocandins against high metabolic activity biofilms of Candida parapsilosis clinical isolates(2020) THOMAZ, Danilo Yamamoto; MELHEM, Marcia de Souza Carvalho; ALMEIDA JUNIOR, Joao Nobrega de; BENARD, Gil; NEGRO, Gilda Maria Barbaro DelCandida parapsilosis produces biofilm, which colonizes catheters and other invasive medical devices that are manipulated by health care workers. In previous studies, C. parapsilosis in vitro biofilms have exhibited high resistance rates against conventional antifungals, but susceptibility to both echinocandins and lipid formulations of amphotericin B (lipid complex and liposomal). However, a recent study showed good activity of amphotericin B deoxycholate on the biomass of C. parapsilosis biofilms. Although moderate activity of echinocandins has been demonstrated against low metabolic activity biofilms of C. parapsilosis, few studies have analyzed the action of these drugs on high metabolic activity biofilms. Moreover, high biofilm-forming isolates have been associated with central venous catheter-related fungemia outbreaks and higher mortality rates. Therefore, it is relevant to verify the activity of the main antifungal drugs against high metabolic activity biofilms of C. parapsilosis. Our study aimed to evaluate the in vitro activity of amphotericin B deoxycholate, anidulafungin, caspofungin, and micafungin against high biofilm-forming and high metabolic activity clinical isolates of C. parapsilosis. Our results showed good activity of amphotericin B against C. parapsilosis biofilms, but none of the echinocandin drugs was effective. This suggests that amphotericin B deoxycholate may be a better choice than echinocandins for the treatment of biofilm-associated infections by C. parapsilosis, mainly in countries with insufficient health care resources to purchase lipid formulations of amphotericin B. These results warn of the possibility of persistent catheter-related candidemia caused by high biofilm-forming C. parapsilosis strains when treated with echinocandin drugs.
- Environmental Clonal Spread of Azole-Resistant Candida parapsilosis with Erg11-Y132F Mutation Causing a Large Candidemia Outbreak in a Brazilian Cancer Referral Center(2021) THOMAZ, Danilo Y.; ALMEIDA, Joao N. de; SEJAS, Odeli N. E.; NEGRO, Gilda M. B. Del; CARVALHO, Gabrielle O. M. H.; GIMENES, Viviane M. F.; SOUZA, Maria Emilia B. de; ARASTEHFAR, Amir; CAMARGO, Carlos H.; MOTTA, Adriana L.; ROSSI, Flavia; PERLIN, David S.; FREIRE, Maristela P.; ABDALA, Edson; BENARD, GilClonal outbreaks due to azole-resistant Candida parapsilosis (ARCP) isolates have been reported in numerous studies, but the environmental niche of such isolates has yet to be defined. Herein, we aimed to identify the environmental niche of ARCP isolates causing unremitting clonal outbreaks in an adult ICU from a Brazilian cancer referral center. C. parapsilosis sensu stricto isolates recovered from blood cultures, pericatheter skins, healthcare workers (HCW), and nosocomial surfaces were genotyped by multilocus microsatellite typing (MLMT). Antifungal susceptibility testing was performed by the EUCAST (European Committee for Antimicrobial Susceptibility Testing) broth microdilution reference method and ERG11 was sequenced to determine the azole resistance mechanism. Approximately 68% of isolates were fluconazole-resistant (76/112), including pericatheter skins (3/3, 100%), blood cultures (63/70, 90%), nosocomial surfaces (6/11, 54.5%), and HCW's hands (4/28, 14.2%). MLMT revealed five clusters: the major cluster contained 88.2% of ARCP isolates (67/76) collected from blood (57/70), bed (2/2), pericatheter skin (2/3), from carts (3/7), and HCW's hands (3/27). ARCP isolates were associated with a higher 30 day crude mortality rate (63.8%) than non-ARCP ones (20%, p = 0.008), and resisted two environmental decontamination attempts using quaternary ammonium. This study for the first time identified ARCP isolates harboring the Erg11-Y132F mutation from nosocomial surfaces and HCW's hands, which were genetically identical to ARCP blood isolates. Therefore, it is likely that persisting clonal outbreak due to ARCP isolates was fueled by environmental sources. The resistance of Y132F ARCP isolates to disinfectants, and their potential association with a high mortality rate, warrant vigilant source control using effective environmental decontamination.
- Breakthrough Candidemia in Pediatric Patients With Cancer From a Brazilian Center(2021) BARRIENTOS, Anna Carlota Mott; ALMEIDA JUNIOR, Joao Nobrega de; LITVINOV, Nadia; BAIN, Vera; CRISTOFANI, Lilian Maria; PEREIRA, Maria Fernanda Badue; PAULA, Camila Sanson Yoshino de; MOTTA, Adriana Lopes; ROSSI, Flavia; NEGRO, Gilda Maria Barbaro Del; THOMAZ, Danilo Yamamoto; MARQUES, Heloisa Helena SousaWe analyzed 19 cases of breakthrough candidemia from a referral pediatric cancer center in Brazil. All patients had neutropenia and were under antifungal prophylactic regimens, mostly micafungin (68%). Most of the patients were treated with amphotericin B formulations and 30-day mortality was 21%. Candida parapsilosis was the main etiologic agent (63%), and horizontal transmission was not evidenced by microsatellite analysis.
- Does the Capsule Interfere with Performance of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for Identification of Cryptococcus neoformans and Cryptococcus gattii?(2016) THOMAZ, Danilo Y.; GRENFELL, Rafaella C.; VIDAL, Monica S. M.; GIUDICE, Mauro C.; NEGRO, Gilda M. B. Del; JULIANO, Luiz; BENARD, Gil; ALMEIDA JUNIOR, Joao N. deWe described the impact of the capsule size for Cryptococcus neoformans and Cryptococcus gattii identification at the species level by Bruker matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). After experimental capsule size modulation, we observed that reducing the capsule size resulted in improved identification by Bruker MALDI-TOF MS across all of the reference strains analyzed.