FLAVIA ROSSI
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
LIM/03 - Laboratório de Medicina Laboratorial, Hospital das Clínicas, Faculdade de Medicina
31 resultados
Resultados de Busca
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- High prevalence of OXA-143 and alteration of outer membrane proteins in carbapenem-resistant Acinetobacter spp. isolates in Brazil(2012) MOSTACHIO, Anna Karina; LEVIN, Anna Sara; RIZEK, Camila; ROSSI, Flavia; ZERBINI, Jessika; COSTA, Silvia FigueiredoCarbapenem resistance amongst Acinetobacter spp. has been increasing in the last decade. This study evaluated the outer membrane protein (OMP) profile and production of carbapenemases in 50 carbapenem-resistant Acinetobacter spp. isolates from bloodstream infections. Isolates were identified by API20NE. Minimum inhibitory concentrations (MICs) for carbapenems were determined by broth microdilution. Carbapenemases were studied by phenotypic tests, detection of their encoding gene by polymerase chain reaction (PCR) amplification, and imipenem hydrolysis. Nucleotide sequencing confirming the enzyme gene type was performed using MegaBACE 1000. The presence of OMPs was studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and PCR. Molecular typing was performed using pulsed-field gel electrophoresis (PFGE). All isolates were resistant to carbapenems. Moreover, 98% of the isolates were positive for the gene encoding the enzyme OXA-51-like, 18% were positive for OXA-23-like (only one isolate did not show the presence of the insertion sequence ISAba1 adjacent to this gene) and 76% were positive for OXA-143 enzyme. Five isolates (10%) showed the presence of the IMP-1 gene. Imipenem hydrolysing activity was detected in only three strains containing carbapenemase genes, comprising two isolates containing the bla(IMP) gene and one containing the bla(OXA-51/OXA-23-like) gene. The OMP of 43 kDa was altered in 17 of 25 strains studied, and this alteration was associated with a high meropenem MIC (256 mu g/mL) in 5 of 7 strains without 43 kDa OMP. On the other hand, decreased OMP 33-36 kDa was found in five strains. The high prevalence of OXA-143 and alteration of OMPs might have been associated with a high level of carbapenem resistance.
- 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
- Clusters of infection due to metallo-beta-lactamase-producing Pseudomonas aeruginosa in stem cell transplant and haematology units(2011) PAEZ, J.; LEVIN, A. S.; FU, L.; BASSO, M.; FONSECA, G. H. H.; DULLEY, F. L.; ROSSI, F.; GUIMARAES, T.; COSTA, S. F.
- Clinical outcome from hematopoietic cell transplant patients with bloodstream infection caused by carbapenem-resistant P. aeruginosa and the impact of antimicrobial combination in vitro(2022) RAMOS, Jessica Fernandes; LEITE, Gleice; MARTINS, Roberta Cristina Ruedas; RIZEK, Camila; SANABANI, Sabri Saeed Al; ROSSI, Flavia; GUIMARAES, Thais; LEVIN, Anna Sara; ROCHA, Vanderson; COSTA, Silvia FigueiredoBloodstream infection (BSI) caused by carbapenem-resistant P. aeruginosa (CRPA) has high mortality in hematopoietic stem cell transplant (HSCT) recipients. We performed MIC, checkerboard, time-kill assay, PFGE, PCR, and whole genome sequence and described the clinical outcome through Epi Info comparing the antimicrobial combination in vitro. Mortality was higher in BSI caused by CRPA carrying the lasB virulence gene. The isolates were 97% resistant to meropenem displaying synergistic effect to 57% in combination with colistin. Seventy-three percent of the isolates harbored bla(SPM-1) and Tn4371 and belonged to ST277. The synergistic effect in vitro with meropenem with colistin appeared to be a better therapeutic option.
- The changing epidemiology of Acinetobacter spp. producing MA. carbapenemases causing bloodstream infections in Brazil: a BrasNet report(2015) VASCONCELOS, Ana Tereza R.; BARTH, Afonso L.; ZAVASCKI, Alexandre P.; GALES, Ana C.; LEVIN, Anna S.; LUCAREVSCHI, Bianca R.; CABRAL, Blenda G.; BRASILIENSE, Danielle M.; ROSSI, Flavia; FURTADO, Guilherme H. C.; CARNEIRO, Irna Carla R. S.; SILVA, Juliana O. da; RIBEIRO, Julival; LIMA, Karla V. B.; CORREA, Luci; BRITTO, Maria H.; SILVA, Mariama T.; CONCEICAO, Marilia L. da; MOREIRA, Marina; MARTINO, Marines D. V.; FREITAS, Manse R. de; OLIVEIRA, Maura S.; DALBEN, Mirian F.; GUZMAN, Ricardo D.; CAYO, Rodrigo; MORAIS, Rosangela; SANTOS, Sania A.; MARTINS, Willames M. B. S.We evaluated the epidemiology of Acinetobacter spp. recovered from patients diagnosed with bloodstream infections in 9 tertiary hospitals located in all Brazilian geographic regions between April and August 2014. Although OXA-23-producing Acinetobacter baumannii clones were disseminated in most hospitals, it was observed for the first time the spread of OXA-72 among clonally related A. baumannii isolated from distinct hospitals. Interestingly, Acinetobacter pittii was the most frequent species found in a Northern region hospital. Contrasting with the multisusceptible profile displayed by A. pittii isolates, the tetracyclines and polymyxins were the only antimicrobials active against all A. baumannii isolates.
- Comparison of methods for the detection of in vitro synergy in multidrug-resistant gram-negative bacteria(2020) GAUDERETO, Juliana Januario; PERDIGAO NETO, Lauro Vieira; LEITE, Gleice Cristina; SANCHEZ, Evelyn; MARTINS, Roberta Cristina Ruedas; PRADO, Gladys Villas Boas; ROSSI, Flavia; GUIMARAES, Thais; LEVIN, Anna Sara; COSTA, Silvia FigueiredoBackground The use of combined antibiotic therapy has become an option for infections caused by multidrug-resistant (MDR) bacteria. The time-kill (TK) assay is considered the gold standard method for the evaluation of in vitro synergy, but it is a time-consuming and expensive method. The purpose of this study was to evaluate two methods for testing in vitro antimicrobial combinations: the disk diffusion method through disk approximation (DA) and the agar gradient diffusion method via the MIC:MIC ratio. The TK assay was included as the gold standard. MDR Gram-negative clinical isolates (n = 62; 28 Pseudomonas aeruginosa, 20 Acinetobacter baumannii, and 14 Serratia marcescens) were submitted to TK, DA, and MIC:MIC ratio synergy methods. Results Overall, the agreement between the DA and TK assays ranged from 20 to 93%. The isolates of A. baumannii showed variable results of synergism according to TK, and the calculated agreement was statistically significant in this species against fosfomycin with meropenem including colistin-resistant isolates. The MIC:MIC ratiometric agreed from 35 to 71% with TK assays. The kappa test showed good agreement for the combination of colistin with amikacin (K = 0.58; P = 0.04) among the colistin-resistant A. baumannii isolates. Conclusions The DA and MIC:MIC ratiometric methods are easier to perform and might be a more viable tool for clinical microbiology laboratories.
- Methicillin-resistant Staphylococcus aureus carrying SCCmec type II was more frequent than the Brazilian endemic clone as a cause of nosocomial bacteremia(2013) CAIAFFA-FILHO, Helio Hehl; TRINDADE, Priscila A.; CUNHA, Paula Gabriela da; ALENCAR, Cecilia Salete; PRADO, Gladys V. B.; ROSSI, Flavia; LEVIN, Anna S.Fifty consecutive MRSA blood isolates were evaluated: 30(60%) carried SCCmec type II (single PFGE clone; sequence type 5 or ST105); 12 (26%), IV; 5 (10%), III; 3 (6%), I. Brazilian endemic clone, carrying SCCmec type III, has been the main nosocomial clone in Brazil; however, this study showed that a clone carrying. type II predominated.
- Carbapenem-resistant Enterobacteriaceae in patients admitted to the emergency department: prevalence, risk factors, and acquisition rate(2017) SALOMAO, M. C.; GUIMARAES, T.; DUAILIBI, D. F.; PERONDI, M. B. M.; LETAIF, L. S. H.; MONTAL, A. C.; ROSSI, F.; CURY, A. P.; DUARTE, A. J. S.; LEVIN, A. S.; BOSZCZOWSKI, I.Background: Carbapenem-resistant Enterobacteriaceae (CRE) have been reported worldwide and are associated with high mortality rates. Intestinal colonization acts as a reservoir and fosters exchange of resistance mechanisms. Aim: To investigate the prevalence of patients harbouring CRE on hospital admission, risk factors associated, and the acquisition rate within the emergency department (ED). Methods: This was a cross-sectional survey with 676 patients consecutively admitted to the ED study during the months of May to July 2016. A questionnaire was performed and rectal swabs were collected from patients on admission, for culture and for multiplex real-time polymerase chain reaction (PCR). If the patient was hospitalized for more than one week in the ED, samples were taken again to determine the acquisition rate of CRE. Findings: Forty-six patients were colonized; all positive PCR were Klebsiella pneumoniae carbapenemase. The acquisition rate was 18%. Previous exposure to healthcare in the last year, liver disease, and use of antibiotics in the last month were risk factors for colonization. Six patients with no previous exposure to healthcare were CRE-colonized on admission, suggesting transmission of CRE within the community. Conclusion: Screening of high-risk patients on admission to the ED is a strategy to early identify CRE carriage and may contribute to control CRE dissemination.
- Colistin-resistant Klebsiella pneumoniae co-harboring KPC and MCR-1 in a Hematopoietic Stem Cell Transplantation Unit(2019) HIGASHINO, Hermes Ryoiti; MARCHI, Ana Paula; MARTINS, Roberta Cristina Ruedas; BATISTA, Marjorie Vieira; PERDIGAO NETO, Lauro Vieira; LIMA, Victor Augusto Camarinha de Castro; ROSSI, Flavia; GUIMARAES, Thais; LEVIN, Anna Sara; ROCHA, Vanderson; COSTA, Silvia Figueiredo
- Genetic and virulence characterization of colistin-resistant and colistin-sensitive A. baumannii clinical isolates(2019) LEITE, Gleice Cristina; STABLER, Richard A.; NEVES, Patricia; PERDIGAO NETO, Lauro V.; MARTINS, Roberta C. Ruedas; RIZEK, Camila; ROSSI, Flavia; LEVIN, Anna S.; COSTA, Silvia FigueiredoTreatment of infections caused by A. baumannii is becoming a challenge due to the ability to develop multidrug-resistance, virulence, and high mortality. We described the colistin resistance and virulence genes present in sixA. baumannii clinical isolates using WGS, expression by qPCR, and virulence in the Galleria mellonella model. The colistin-resistant isolates were assigned as ST233 and the colistin-susceptible isolates as ST236 and ST407. The colistin-resistant isolates contained mutations within PmrA/PmrB, and the pmrA showed up-regulation in all of them. Only one colistin-resistant isolate indicating virulence in G. mellonella. This particular isolate belonged to a different clone, and it was the only isolate that presented non-synonymous mutations in pmrB. Colistinresistance in A. baumannii isolates seems to be caused by up-regulation of pmrA gene. Only one isolate appeared to be virulent in the G. mellonella model. This finding indicating low virulence in isolates belonging to emerging clones circulating in our hospital.