ANA PAULA MARCHI ROSIN
Projetos de Pesquisa
Unidades Organizacionais
LIM/49 - Laboratório de Protozoologia, Hospital das Clínicas, Faculdade de Medicina
5 resultados
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- Alternative drugs against multiresistant Gram-negative bacteria(2020) PERDIGAO NETO, Lauro Vieira; OLIVEIRA, Maura Salaroli; ORSI, Tatiana D'Annibale; PRADO, Gladys Villas Boas do; MARTINS, Roberta Cristina Ruedas; LEITE, Gleice Cristina; MARCHI, Ana Paula; LIRA, Esther Sant'Ana de; CORTES, Marina Farrel; ESPINOZA, Evelyn Patricia Sanchez; CARRILHO, Claudia Maria Dantas de Maio; BOSZCZOWSKI, Icaro; GUIMARAES, Thais; COSTA, Silvia Figueiredo; LEVIN, Anna S.Objectives: Enterobacterales and other non-fermenting Gram-negative bacteria have become a threat worldwide owing to the frequency of multidrug resistance in these pathogens. On the other hand, efficacious therapeutic options are quickly diminishing. The aims of this study were to describe the susceptibility of 50 multiresistant Gram-negative bacteria, mostly pan-resistant, against old and less-used antimicrobial drugs and to investigate the presence of antimicrobial resistance genes. Methods: A total of 50 genetically distinct isolates were included in this study, including 14 Acinetobacter baumannii (belonging to ST79, ST317, ST835 and ST836), 1 Pseudomonas aeruginosa (ST245), 8 Serratia marcescens and 27 Klebsiella pneumoniae (belonging to STII, ST340, ST258, ST16, ST23, ST25, ST101, ST234, ST437 and ST442). The isolates were submitted to antimicrobial susceptibility testing and whole-genome sequencing to evaluate lineages and resistance genes. Results: Our results showed that some strains harboured carbapenemase genes, e.g. bla(K)(PC-)(2) (28/50; 56%) and bla(OXA-23) (11/50; 22%), and other resistance genes encoding aminoglycoside-modifying enzymes (49/50; 98%). Susceptibility rates to tigecycline (96%) in all species (except P. aeruginosa), to minocycline (100%) and doxycycline (93%) in A. baumannii, to ceftazidime/avibactam in S. marcescens (100%) and K. pneumoniae (96%), and to fosfomycin in S. marcescens (88%) were high. Chloramphenicol and quinolones (6% susceptibility each) did not perform well, making their use in an empirical scenario unlikely. Conclusions: This study involving genetically distinct bacteria showed promising results for tigecycline for all Gram-negative bacteria (except P. aeruginosa), and there was good activity of minocycline against A. baumannii, ceftazidime/avibactam against Enterobacterales, and fosfomycin against S. marcescens. (C) 2020 The Author(s).
- Phenotypic and genotypic characteristics of a carbapenem-resistant Serratia marcescens cohort and outbreak: describing an opportunistic pathogen(2022) PRADO, Gladys; MENDES, Elisa Teixeira; MARTINS, Roberta Cristina Ruedas; PERDIGAO-NETO, Lauro Vieira; FREIRE, Maristela Pinheiro; MARCHI, Ana Paula; CORTES, Marina Farrel; LIMA, Victor Augusto Camarinha de Castro; ROSSI, Flavia; GUIMARAES, Thais; LEVIN, Anna Sara; COSTA, Silvia FigueiredoSerratia marcescens is an emerging opportunistic pathogen with high genetic diversity. This article describes the microbiological characteristics of isolates and the risk factors for infections caused by carbapenem-resistant S. marcescens. A retrospective study of patients colonized (n=43) and infected (n= 20) with carbapenem-resistant S. marcescens over a 3-year period was conducted. Polymerase chain reaction for carbapenemase genes and molecular typing of all available strains was performed. Forty-two isolates were analysed, including three environmental samples identified during an outbreak. Thirty-five carbapenem-resistant S. marcescens carried bla KPC-2, one isolate was bla(NDM)-positive and four isolates carried bla(OXA)-101. The genomes were grouped into three clusters with 100% bootstrap; three patterns of mutations on ompC and ompF were found. The strains carried virulence genes related to invasion and haemolysis, and the environmental strains presented fewer mutations on the virulence genes than the clinical strains. Multi-variate analysis showed that previous use of polymyxin (P= 0.008) was an independent risk factor for carbapenem-resistant S. marcescens infection. This study highlighted that bla KPC-2 in association with ompC or ompF mutation was the most common mechanism of resistance in the study hospital, and that previous use of polymyxin was an independent risk factor for carbapenem-resistant S. marcescens. There was a predominant clone, including the environmental isolates, suggesting that crosstransmission was involved in the dissemination of this pathogen.
- Virulence and resistance pattern of a novel sequence type of linezolid-resistant Enterococcus faecium identified by whole-genome sequencing(2016) PRADO, Gladys Villas Boas do; MARCHI, Ana Paula; MORENO, Luisa Zanolli; RIZEK, Camila; AMIGO, Ulisses; MORENO, Andrea Micke; ROSSI, Flavia; GUIMARAES, Thais; LEVIN, Anna Sara; COSTA, Silvia F.Empirical use of linezolid has been advocated in neutropenic febrile patients colonised by vancomycin-resistant enterococci (VRE) because of the risk of bloodstream infection (BSI). This study aimed to genetically describe a vancomycin-resistant Enterococcus faecium (VREfm) BSI isolate resistant to linezolid (VRLRE) in a patient previously colonised by VREfm and to determine the incidence of colonisation and infection by VREfm in a bone marrow transplant unit over a 10-year period. Data for VREfm colonisation and infection were evaluated. PCR for the vanA and vanB genes, pulsed-field gel electrophoresis (PFGE) and microdilution antimicrobial susceptibility testing (vancomycin, teicoplanin, linezolid and aminoglycosides) were performed. Three isolates, including the VRLRE, were selected for whole-genome sequencing by Ion Torrent (TM), with E. faecium CP006620-Aus0085 used as a reference. Eighty-seven VREfm were analysed; all were linezolid-susceptible and harboured vanA, except for one blood isolate from a febrile neutropenic patient colonised by VREfm who received linezolid for 12 days and developed a BSI by VRLRE (linezolid MIC >= 8 mu g/mL). Linezolid resistance was associated with a G2576T mutation in the 23SrRNA gene. PFGE analysis demonstrated that the 87 isolates belonged to four major clusters; however, the VRLRE presented only 50% similarity. Three sequence types (STs) were identified: ST412 (the predominant clone, which was more virulent compared with the other isolates); ST478 (linezolid-susceptible VREfm); and a novel ST named ST987 (VRLRE). SNP analysis showed a higher similarity between linezolid-susceptible VREfm and the predominant clone compared with VRLRE. VRLRE presented a G2576T mutation and belonged to a novel ST (ST987).
- Fosfomycin in severe infections due to genetically distinct pan-drug-resistant Gram-negative microorganisms: synergy with meropenem(2019) PERDIGAO NETO, Lauro Vieira; OLIVEIRA, Maura S.; MARTINS, Roberta Cristina Ruedas; MARCHI, Ana Paula; GAUDERETO, Juliana Januario; COSTA, Lucianna Auxi Teixeira Josino da; LIMA, Lia Fernandes Alves de; TAKEDA, Christianne Fernandes Valente; COSTA, Silvia F.; LEVIN, Anna S.Background: In vitro and clinical studies using parenteral fosfomycin have suggested the possibility of using this drug against infections caused by MDR microorganisms. The aim of this study was to describe a case series of patients treated with fosfomycin who had severe infections caused by pan-drug-resistant Gram-negative bacteria. Methods: We describe a prospective series of cases of hospitalized patients with infections caused by Gram-negative bacteria resistant to beta-lactams and colistin, treated with 16 g of fosfomycin daily for 10-14 days. Isolates were tested for antimicrobial susceptibility and synergism of fosfomycin with meropenem. We tested for resistance genes and performed typing using PCR and WGS. Results: Thirteen patients received fosfomycin (seven immunosuppressed); they had bloodstream infections (n = 11; 85%), ventilator-associated pneumonia (n = 1; 8%) and surgical site infection (n = 1; 8%), caused by Klebsiella pneumoniae (n = 9), Serratia marcescens (n = 3) and Pseudomonas aeruginosa (n = 1). Overall, eight (62%) patients were cured. Using time-kill assays, synergism between fosfomycin and meropenem occurred in 9 (82%) of 11 isolates. Typing demonstrated that K. pneumoniae were polyclonal. Eight patients (62%) had possible adverse events, but therapy was not discontinued. Conclusions: Fosfomycin may be safe and effective against infections caused by pan-drug-resistant Gram-negative microorganisms with different antimicrobial resistance mechanisms and there seems to be synergism with meropenem.
- Virulomic Analysis of Multidrug-Resistant Klebsiella pneumoniae Isolates and Experimental Virulence Model Using Danio rerio (Zebrafish)(2022) DUARTE, Edson Luiz Tarsia; RIZEK, Camila Fonseca; ESPINOZA, Evelyn Sanchez; MARCHI, Ana Paula; NOGUERA, Saidy Vasconez; CORTES, Marina Farrel; FERNANDES, Bianca H. Ventura; GUIMARAES, Thais; CARRILHO, Claudia M. D. de Maio; V, Lauro Perdigao Neto; TRINDADE, Priscila A.; COSTA, Silvia FigueiredoThis study evaluates a possible correlation between multidrug-resistant Klebsiella pneumoniae strains and virulence markers in a Danio rerio (zebrafish) model. Whole-genome sequencing (WGS) was performed on 46 strains from three Brazilian hospitals. All of the isolates were colistin-resistant and harbored bla(KPC-2). Ten different sequence types (STs) were found; 63% belonged to CC258, 22% to ST340, and 11% to ST16. The virulence factors most frequently found were type 3 fimbriae, siderophores, capsule regulators, and RND efflux-pumps. Six strains were selected for a time-kill experiment in zebrafish embryos: infection by ST16 was associated with a significantly higher mortality rate when compared to non-ST16 strains (52% vs. 29%, p = 0.002). Among the STs, the distribution of virulence factors did not differ significantly except for ST23, which harbored a greater variety of factors than other STs but was not related to a higher mortality rate in zebrafish. Although several virulence factors are described in K. pneumoniae, our study found ST16 to be the only significant predictor of a virulent phenotype in an animal model. Further research is needed to fully understand the correlation between virulence and sequence types.