LAURO VIEIRA PERDIGAO NETO
Projetos de Pesquisa
Unidades Organizacionais
LIM/49 - Laboratório de Protozoologia, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
Agora exibindo 1 - 4 de 4
- Multidrug-resistant Stenotrophomonas maltophilia: Description of new MLST profiles and resistance and virulence genes using whole-genome sequencing(2018) RIZEK, Camila Fonseca; JONAS, Daniel; PAEZ, Jorge Isaac Garcia; ROSA, Juliana Ferraz; PERDIGAO NETO, Lauro Vieira; MARTINS, Roberta Ruedas; MORENO, Luisa Z.; ROSSI JUNIOR, Alfio; LEVIN, Anna S.; COSTA, Silvia FigueiredoObjectives: Stenotrophomonas maltophilia is an opportunistic pathogen that has high intrinsic and acquired antimicrobial resistance, with great genetic diversity. The aim of this study was to characterise four S. maltophilia clinical isolates displaying different susceptibility profiles using whole-genome sequencing. Methods: The whole genomes of four clinical isolates of S. maltophilia from three patients were sequenced using Ion Torrent (TM) PGM technology. The isolates presented different susceptibilities to trimethoprim/sulfamethoxazole (SXT) and levofloxacin. Results: Three new multilocus sequence typing (MLST) profiles were identified (ST144, ST172 and ST173), differing in virulence and resistance genes. The ST172 isolate had more genes related to toxins than related to motility or adhesion and had different types of efflux pumps than the other isolates. The SXT-resistant strains belonged to ST172 or ST144 and did not harbour the sul1, sul2 or dfrA resistance genes. Strains I and II, from the same patient and belonging to the same ST but differing in resistance to SXT, had all of the resistance genes searched for in common, except for the SmeABC efflux pump complex genes that were only found in the SXT-resistant strain. All strains, including the strain susceptible to levofloxacin, harboured the qnrB gene, which may question the importance of this gene in determining levofloxacin resistance in S. maltophilia. Conclusion: Here we describe three new MLST profiles. Resistance to SXT in these strains appears to be associated with efflux pumps.
- 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).
- Polymyxin-resistant Pseudomonas aeruginosa assigned as ST245: First report in an intensive care unit in Sao Paulo, Brazil(2019) ORSI, Tatiana D'Annibale; PERDIGAO NETO, Lauro Vieira; MARTINS, Roberta Cristina Ruedas; LEVIN, Anna S.; COSTA, Silvia FigueiredoObjectives: Pseudomonas aeruginosa is a Gram-negative bacterium that causes severe infections, especially in hospitalised and immunocompromised patients. Polymyxins are the last therapeutic option to treat infections caused by this micro-organism. Here we describe a polymyxin-resistant P. aeruginosa assigned as sequence type (ST) 245 for the first time in Brazil. Methods: Antimicrobial susceptibility testing of the isolate was performed. In addition, whole-genome sequencing was performed and its virulence and resistance genes were analysed. Results: The P. aeruginosa ST245 isolate was identified for the first time in Brazil in a patient with ventilator-associated pneumonia hospitalised at Hospital das Clinicas, Sao Paulo. Analysis of the genome showed the presence of several resistance and virulence genes. Mutations in beta-lactam resistance genes were found in beta-lactamases, outer membrane proteins, efflux pump and penicillin-binding proteins. Polymorphisms related to pathways leading to polymyxin resistance are also present, such as lipid A or keto-deoxyoctulosonate modification with aminoarabinose as well as activation of lipopolysaccharide (LPS). Conclusion: Such findings may represent an alert for the spread of an unusual profile in the country.
- Carbapenem-resistant Pseudomonas aeruginosa carrying bla(VIM-36) assigned to ST308: Indicated non-virulence in a Galleria mellonella model(2019) NEVES, Patricia R.; PERDIGAO NETO, Lauro Vieira; MARTINS, Roberta Cristina Ruedas; RAMOS, Jessica F.; LEITE, Gleice; ROSSI, Flavia; SANABANI, Sabri Saeed; ROCHA, Vanderson; BATISTA, Marjorie Vieira; GUIMARAES, Thais; LEVIN, Anna S.; COSTA, Silvia F.Objectives: Based on pulsed-field gel electrophoresis (PFGE) profile, whole-genome sequencing (WGS) of eight carbapenem-resistant Pseudomonas aeruginosa isolates from a bone marrow transplant unit in Sao Paulo, Brazil, was performed to investigate the presence of resistance and virulence genes as well as to determine the sequence type (ST) by multilocus sequence typing (MLST). Methods: The initial phenotypic susceptibility pattern of the isolates was determined by VITEK (R) 2. Minimum inhibitory concentrations (MICs) were determined by the broth microdilution method for amikacin, meropenem and colistin. WGS was performed using an Illumina MiSeq system. A Galleria mellonella infection model was used to evaluate the virulence of the strains. Results: WGS demonstrated that mutations in genes encoding outer membrane proteins and efflux pumps in an isolate harbouring bla(VIM-36) (ST308) differed from those in isolates harbouring bla(SPM)(ST277). The mexTgene harboured a mutation resulting in a frameshift in all isolates; in addition, the oprD gene of the bla(VIM-36)-carrying isolate had an insertion leading to a frameshift. Virulence genes did not differ between ST277 and ST308 strains. Moreover, only two isolates harbouring bla(SPM) showed virulence in the G. mellonella model, killing 100% of larvae after 18-24 h. Conclusions: P. aeruginosa carrying bla(VIM-36) belonging to ST308 was identified for the first time in our hospital. Although the virulence gene profiles were similar in isolates carrying bla(SPM )and the isolate carrying bla(VIM-36), only two isolates harbouring bla(SPM )showed virulence in the G. mellonella model.