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1.
Microbiol Immunol ; 68(1): 1-5, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37859304

RESUMO

Over the last decade, New Delhi metallo-beta-lactamase (NDM) carbapenemase has silently spread in Brazil. In this study, we analyzed a large collection of Enterobacterales other than Klebsiella spp. received in our reference laboratory between 2013 and 2022. A total of 32 clinical isolates displaying different pulsed-field gel electrophoresis profiles, and represented by 11 species in the families Enterobacteriaceae (Citrobacter freundii, Citrobacter portucalensis, Enterobacter hormaechei, and Escherichia coli), Morganellaceae (Morganella morganii, Proteus mirabilis, Proteus vulgaris, Providencia rettgeri, Providencia stuartii, and Raoultella ornithinolytica), and Yersiniaceae (Serratia marcescens) had their whole genomes sequenced and further analyzed. Antimicrobial susceptibility was determined by disk diffusion, except for polymyxin B, assessed by broth microdilution. The blaNDM-1 allele was predominant (n = 29), but blaNDM-5 was identified in an E. coli specimen with a novel ST, and the blaNDM-7 allele was found in E. hormaechei ST45 and E. coli ST1049. Polymyxin was active against all but one Enterobacteriaceae isolate: an mcr-1-producing E. coli presenting minimal inhibitory concentration (4 mg/L). Isolates producing extended-spectrum ß-lactamases were common: cefotaximase from Munich (CTX-M)-15 (n = 10), CTX-M-2 (n = 4), and CTX-M-8 (n = 3) were detected, and the mcr-1-producing E. coli was found to co-produce both CTX-M-8 and CTX-M-55 ß-lactamases. The mcr-9 gene was found in 5/8 E. hormaechei isolates, distributed in four different sequence types, all of them presenting susceptibility to polymyxin. This study showed that NDM-producing Enterobacterales other than Klebsiella are already spread in Brazil, in diversified species, and cocarrying important resistance genes. Prompt detection and effective implementation of measures to prevent further spread are mandatory for mitigating the dissemination of NDM carbapenemase in hospital settings and preserving the already limited antimicrobial therapy options.


Assuntos
Infecções por Enterobacteriaceae , Escherichia coli , Humanos , Klebsiella/genética , Brasil/epidemiologia , Antibacterianos/farmacologia , beta-Lactamases/genética , Infecções por Enterobacteriaceae/epidemiologia , Genômica , Testes de Sensibilidade Microbiana , Polimixinas/farmacologia
2.
Curr Microbiol ; 79(9): 250, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35834136

RESUMO

Emergence of resistance to classical antimicrobial agents is a public health issue, especially in countries with high antimicrobial consumption rates. Carbapenems have been employed as first-choice option for empirical treatment complicated infections. However, in the last decades, frequency of carbapenemase-producing Gram-negative bacteria has rising, demanding the use of alternative antimicrobial agents. By sequencing the entire genomes with short and long reads technologies, we report the isolation and genomic characterization of a carbapenem-resistant Pseudomonas clinical isolate. The identification based on average nucleotide identity indicates a putative new species into the Pseudomonas putida Group, which carries both the blaBKC-1 and blaVIM-2 carbapenemase genes. The blaBKC-1 was found to be on a transferable IncQ plasmid backbone, whereas blaVIM-2 was found in a new integron, In2126 (intl1∆-blaVIM-2-aacA7-blaVIM-2∆-aacA27-3'CS), described in this study. Our findings indicate that co-occurrence of classes A and B carbapenemase enzymes underscores the evolving emergence of more complex antimicrobial resistance in opportunistic pathogens.


Assuntos
Pseudomonas putida , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Brasil , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , Pseudomonas , Pseudomonas putida/genética , beta-Lactamases/genética
3.
J Med Microbiol ; 73(2)2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38305283

RESUMO

Introduction. Disease caused by non-tuberculous mycobacteria (NTM) is an emergent problem. Because NTM pulmonary disease and tuberculosis (TB) have similar clinical presentations, many cases of NTM may be misdiagnosed as TB before laboratory identification of the NTM species.Hypothesis/Gap Statement. Clinical laboratories should always perform differentiation between Mycobacterium tuberculosis complex (MTBC) and NTM to guide patients' correct treatment.Aim. To describe the characteristics and to identify mycobacterial isolates presumptively classified as MTBC by macroscopic characteristics in culture media that tested negative in GenoType MTBDRplus.Methodology. All cultures from February 2019 to December 2021 showing MTBC macroscopic characteristics were processed by GenoType MTBDRplus. MTBC-negative cultures underwent species identification by immunochromatography, line probe assays and PRA-hsp65. Patients' data were obtained from Brazilian surveillance systems.Results. Only 479 (3.1%) of 15 696 isolates presumptively identified as MTBC were not confirmed by GenoType MTBDRplus and were then subjected to identification. A total of 344 isolates were shown to be NTM, of which 309 (64.5%) and 35 (7.3%) were identified to the species and genus levels, respectively. Of the 204 NTM isolates with MTBC characteristics, the most frequent species were M. fortuitum (n=52, 25.5%), M. abscessus complex (MABC; n=27, 13.2%) and M. avium complex (MAC; n=26, 12.7%). Regarding the GenoType MTBDRplus results from NTM isolates, there were diverse hybridisation profiles with rpoB gene's different wild-type (WT) probes. Seventy-six (16.1%) of the 473 patients were classified as having NTM disease, the most frequent being MAC (n=15, 19.7%), MABC (n=13, 17.1%), M. kansasii (n=10, 13.2%) and M. fortuitum (n=6, 7.9%).Conclusion. Because the signs and symptoms of pulmonary TB are similar to those of pulmonary mycobacteriosis and treatment regimens for TB and NTM are different, identifying the disease-causing species is paramount to indicate the correct management. Thus, in the laboratory routine, when an isolate presumptively classified as MTBC is MTBC-negative, it is still essential to perform subsequent identification.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Tuberculose Pulmonar , Tuberculose , Humanos , Micobactérias não Tuberculosas , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose/diagnóstico , Tuberculose/microbiologia , Genótipo
4.
Microorganisms ; 12(7)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39065176

RESUMO

Public health faces daily challenges due to increasing reports of pathogenic microorganisms with new antimicrobial resistance. Klebsiella michiganensis, an emerging pathogen, poses difficulty in its identification using conventional techniques. This study presents the first documented case of NDM-1-producing K. michiganensis in Brazil, identified as the new ST418. Initially, the isolate from a tracheal secretion was misidentified as K. oxytoca. However, accurate identification was achieved through ANI analyses. Whole-genome sequencing was conducted to characterize the genetic context of the resistance genes, to identify virulence factors, and to construct a phylogenetic tree. The blaNDM-1 gene was found to be harbored on an IncFIB plasmid approximately 112 kb in length, which was transferable in conjugation assays. The detection of carbapenem resistance genes in this species highlights the importance of public health vigilance, as it may serve as a reservoir and disseminator of significant resistance genes.

5.
J Med Microbiol ; 72(3)2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36920844

RESUMO

Introduction. The M. abscessus molecular identification and its drug-resistance profile are important to choose the correct therapy.Aim. This work developed a multiplex real-time PCR (mqPCR) for detection of clarithromycin resistance genes for the Mycobacterium abscessus group.Methodology. Isolates received by Adolfo Lutz Institute from 2010 to 2012, identified by PCR restriction enzyme analysis of a fragment of the hsp65 gene (PRA-hsp65) as M. abscessus type 1 (n=135) and 2 (n=71) were used. Drug susceptibility test (DST) for CLA were performed with reading on days 3 and 14. Subespecies identification by hsp65 and rpoB genes sequencing and erm(41) and rrl genes for mutation detection and primer design were performed. erm(41) gene deletion was detected by conventional PCR. Primers and probes were designed for five detections: erm(41) gene full size and with deletion; erm(41) gene T28 and C28; rrl gene A2058.Results. In total, 191/206 (92.7 %) isolates were concordant by all methods and 13/206 (6.3 %) were concordant only between molecular methods. Two isolates (1.0 %) were discordant by mqPCR compared to rrl gene sequencing. The mqPCR obtained 204/206 (99.0 %) isolates in agreement with the gold standard, with sensitivity and specificity of 98 and 100 %, respectively, considering the gold standard method and 92 and 93 % regarding DST.Conclusion. The mqPCR developed by us proved to be an easy-to-apply tool, minimizing time, errors and contamination.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Humanos , Claritromicina/farmacologia , Antibacterianos/farmacologia , Mycobacterium abscessus/genética , Reação em Cadeia da Polimerase em Tempo Real , Testes de Sensibilidade Microbiana , Infecções por Mycobacterium não Tuberculosas/microbiologia , Farmacorresistência Bacteriana/genética
6.
Sci Rep ; 13(1): 14603, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37670032

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP) are highly disseminated worldwide, and isolates co-resistant to other antimicrobial agents pose a threat to effective antimicrobial therapy. Therefore, evaluation of novel antimicrobial drugs is needed to identify potential treatments with better outcomes. We evaluated the in vitro activity of novel antimicrobial drugs/combinations against 97 KPC-producing Klebsiella pneumoniae isolates recovered from different hospitals in Brazil during 2021-2022. Clonality, resistance and virulence genes were detected by whole-genome sequencing. The majority of the isolates (54.6%) were classified as extensively drug resistant or multidrug resistant (44.3%); one isolate showed a pandrug resistance phenotype. The most active antimicrobial agents were meropenem-vaborbactam, cefiderocol, and ceftazidime-avibactam, with sensitivities higher than 90%; resistance to ceftazidime-avibactam was associated with KPC-33 or KPC-44 variants. Colistin and polymyxin B were active against 58.6% of the isolates. The 97 isolates were distributed into 17 different sequence types, with a predominance of ST11 (37.4%). Although high in vitro susceptibility rates were detected for meropenem-vaborbactam and cefiderocol, only ceftazidime-avibactam is currently available in Brazil. Our findings showed limited susceptibility to antimicrobial drugs employed for infection treatment of carbapenem-resistant K. pneumoniae, underscoring the urgent need for stringent policies for antimicrobial stewardship to preserve the activity of such drugs.


Assuntos
Lactamas , Inibidores de beta-Lactamases , Brasil , Klebsiella pneumoniae , Meropeném , Genômica , Carbapenêmicos , Cefiderocol
7.
Pathogens ; 12(7)2023 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-37513765

RESUMO

Pseudomonas aeruginosa, an opportunistic pathogen causing infections in immunocompromised patients, usually shows pronounced antimicrobial resistance. In recent years, the frequency of carbapenemases in P. aeruginosa has decreased, which allows use of new beta-lactams/combinations in antimicrobial therapy. Therefore, the in vitro evaluation of these drugs in contemporary isolates is warranted. We evaluated the antimicrobial susceptibility and genomic aspects of 119 clinical P. aeruginosa isolates from 24 different hospitals in Brazil in 2021-2022. Identification was performed via MALDI-TOF-MS, and antimicrobial susceptibility was identified through broth microdilution, gradient tests, or disk diffusion. Whole-genome sequencing was carried out using NextSeq equipment. The most active drug was cefiderocol (100%), followed by ceftazidime-avibactam (94.1%), ceftolozane-tazobactam (92.4%), and imipenem-relebactam (81.5%). Imipenem susceptibility was detected in 59 isolates (49.6%), and the most active aminoglycoside was tobramycin, to which 99 (83.2%) isolates were susceptible. Seventy-one different sequence types (STs) were detected, including twelve new STs described herein. The acquired resistance genes blaCTX-M-2 and blaKPC-2 were identified in ten (8.4%) and two (1.7%) isolates, respectively. Several virulence genes (exoSTUY, toxA, aprA, lasA/B, plcH) were also identified. We found that new antimicrobials are effective against the diverse P. aeruginosa population that has been circulating in Brazilian hospitals in recent years.

8.
Antibiotics (Basel) ; 11(10)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36290053

RESUMO

Background: Since its first report in the country in 2013, NDM-producing Enterobacterales have been identified in all the Brazilian administrative regions. In this study, we characterized by antimicrobial susceptibility testing and by molecular typing a large collection of NDM-producing Klebsiella isolates from different hospitals in Brazil, mainly from the state of Sao Paulo, over the last decade. Methods: Bacterial isolates positive for blaNDM-genes were identified by MALDI-TOF MS and submitted to antimicrobial susceptibility testing by disk diffusion or broth microdilution (for polymyxin B). All isolates were submitted to pulsed-field gel electrophoresis, and isolates belonging to different clusters were submitted to whole genome sequencing by Illumina technology and downstream analysis. Mating out assays were performed by conjugation, plasmid sizes were determined by S1-PFGE, and plasmid content was investigated by hybrid assembly after MinIon long reads sequencing. Results: A total of 135 NDM-producing Klebsiella were identified, distributed into 107 different pulsotypes; polymyxin B was the only antimicrobial with high activity against 88.9% of the isolates. Fifty-four isolates presenting diversified pulsotypes were distributed in the species K. pneumoniae (70%), K. quasipneumoniae (20%), K. variicola (6%), K. michiganensis (a K. oxytoca Complex species, 2%), and K. aerogenes (2%); blaNDM-1 was the most frequent allele (43/54, 80%). There was a predominance of Clonal Group 258 (ST11 and ST340) encompassing 35% of K. pneumoniae isolates, but another thirty-one different sequence types (ST) were identified, including three described in this study (ST6244 and ST6245 for K. pneumoniae, and ST418 for K. michiganensis). The blaNDM-1 and blaNDM-7 were found to be located into IncF and IncX3 type transferable plasmids, respectively. Conclusions: Both clonal (mainly driven by CG258) and non-clonal expansion of NDM-producing Klebsiella have been occurring in Brazil in different species and clones, associated with different plasmids, since 2013.

9.
J Med Microbiol ; 71(4)2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35417321

RESUMO

Introduction. Carbapenem-resistant Acinetobacter baumannii (CRAB) is the primary pathogen causing hospital-acquired infections. The spread of CRAB is mainly driven by the dissemination of resistant clones, and in Latin America, International Clones IC-1 (also known as clonal complex CC1), IC-4 (CC15) and IC-5 (CC79) are the most prevalent.Gap Statement. There are no documented outbreaks of CRAB International Clone 2 (IC-2) reported in Brazil.Aim. To describe a large outbreak of CRAB caused by the uncommon IC-2 in a Brazilian COVID-19 hospital.Methodology. From May 2020 to May 2021, 224 patients infected or colonized with CRAB were identified in a single hospital; 92 % of them were also infected with SARS-CoV-2. From these patients, 137 isolates were recovered and subjected to antimicrobial susceptibility testing, PCR analysis and molecular typing. Whole-genome sequencing and downstream analysis were carried out on a representative isolate (the first available isolate).Results. In 76 % of the patients, a single OXA-23-producing CRAB IC-2 was identified. All the isolates were susceptible to polymyxin B, but highly resistant (>95 %) to aminoglycosides, fluoroquinolones and beta-lactams. Genomic analysis revealed that the representative isolate also carried the 16S rRNA Methylase ArmA, which was detected for the first time in this species in Brazil.Conclusion. We report the rapid spread of an emerging CRAB clone responsible for causing a large outbreak in a hospital in Brazil, a country with predominance of other CRAB clones. Continuous and prospective surveillance is warranted to evaluate the impact of this clone in Brazilian hospital settings.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , COVID-19 , Infecções por Acinetobacter/epidemiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil/epidemiologia , COVID-19/epidemiologia , Células Clonais , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Pandemias , Estudos Prospectivos , RNA Ribossômico 16S , SARS-CoV-2/genética , beta-Lactamases/genética
10.
Infect Genet Evol ; 96: 105104, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34619390

RESUMO

We report the isolation and genomic characterization of a VIM-2 producing Pseudomonas chlororaphis causing bloodstream infection in a newborn in Brazil. A new integron, In2088 (intI1-blaVIM-2-aacA7-aacA27-gcu241), was identified and the first P. chlororaphis genome from a clinical isolate was deposited in public databases.


Assuntos
Infecções por Pseudomonas/microbiologia , Pseudomonas chlororaphis/isolamento & purificação , Sepse/microbiologia , Brasil , Humanos , Recém-Nascido , Integrons/genética , Pseudomonas chlororaphis/enzimologia , Pseudomonas chlororaphis/genética , beta-Lactamases/genética
11.
J Med Microbiol ; 67(5): 683-686, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29570446

RESUMO

Accurate identification of Mycobacterium tuberculosis complex (MTBC) isolates is essential for tuberculosis (TB) control, especially in a high-burden country such as Brazil. Conventional identification methods are laborious and time-consuming, while rapid molecular methods are expensive and require skilled personnel and appropriate physical laboratory infrastructure. Immunochromatographic assays (ICAs) have been shown to provide a rapid and reliable TB diagnosis at a low cost. The use of the SD Bioline TB Ag MPT64 ICA (MPT64 assay) for rapid identification of MTBC clinical isolates in the routine diagnosis of a large-volume reference TB laboratory was evaluated. We analysed 375 isolates on solid and liquid media concurrently with conventional phenotypic methods, the PRA-hsp65 molecular technique and the MPT64 assay. The sensitivity, specificity and accuracy of the ICA were 97.7, 100 and 98.1 %, respectively. The MPT64 assay yielded rapid and accurate results, enabling the treatment to be initiated early and also impacting on TB control.

12.
Am J Infect Control ; 44(11): e221-e226, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27524260

RESUMO

BACKGROUND: The nontuberculous mycobacteria (NTM) are widely spread. In Brazil, 2,520 cases of rapidly growing mycobacteria (RGM) infections after medical procedures were reported, with 5.4% of cases related to nonsurgical invasive procedures and with an occurrence of 1 clone (BRA100) of Mycobacterium abscessus subsp bolletii. OBJECTIVE: To describe a pseudooutbreak of M abscessus subsp bolletii in an endoscopy and bronchoscopy unit. METHODS: The alert for a pseudooutbreak was given when 3 patients, in the same week, had a positive bronchoalveolar lavage culture for M abscessus subsp bolletii. The patients had no symptoms/signs of mycobacterial infection; thus, contamination of bronchoscopes was suspected. Samples for culturing were collected from bronchoscopes, digestive endoscopes, automated disinfection machines, and the water supply. Clinical samples were identified by polymerase chain reaction restriction-enzyme analysis (PRA) of the hsp65 gene and their pulsed-field gel electrophoresis pattern was compared with environmental samples. RESULTS: The investigation demonstrated a contamination of bronchoscopes, digestive endoscopes, and disinfection machines. Molecular typing demonstrated that all strains belonged to the same clone (MAB01), identical to clone BRA100. DISCUSSION: Cross-transmission due to poor disinfection as well as resistance to glutaraldehyde may play roles in the spread of MAB01 M abscessus subsp bolletii, which may have a unique resistance to the environment and adaption to human hosts. However the water supply may have played a role. Attention is needed to ensure the quality of water used to rinse disinfected equipment.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Broncoscópios/microbiologia , Broncoscopia/efeitos adversos , Contaminação de Equipamentos , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium abscessus/isolamento & purificação , Brasil , Eletroforese em Gel de Campo Pulsado , Hospitais , Humanos , Epidemiologia Molecular , Tipagem Molecular , Mycobacterium abscessus/classificação , Mycobacterium abscessus/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
13.
Arq. ciências saúde UNIPAR ; 22(1): 49-53, jan.-abr. 2018. tab, ilus
Artigo em Português | LILACS | ID: biblio-883541

RESUMO

O presente estudo relata o caso de um paciente de difícil tratamento com infecção mista por tuberculose (TB) e micobactérias não tuberculosas (MNT). O paciente é portador de HIV, câncer e outras doenças associadas. A TB foi elucidada em internação devido a quadro de hemoptise. No período da TB/MNT, a carga viral manteve-se indetectável e o Linfócito T CD4+ variou de 117 a 622 cél/mm3. Os principais sintomas foram febre, tosse, emagrecimento e sudorese. O exame de Raio-X mostrou suspeita de TB bilateral cavitária, a baciloscopia foi negativa e várias culturas apresentaram resultado positivo. As identificações dos isolados foram: Complexo Mycobacterium tuberculosis, Mycobacterium intracelullare/chimaera e M. fortuitum, isolados de amostras pulmonares. Iniciado tratamento para TB em outubro de 2015, atualmente tratando de MNT e mantendo cultura positiva com identificação de M. intracelullare. Os Testes de suscetibilidade aos fármacos para M. intracelullare mostraram resistência a Isoniazida, Rifampicina, Ciprofloxacina, Etambutol e Rifabutina. A terapia para a síndrome da imunodeficiência adquirida (AIDS) aumentou a sobrevida do paciente, trazendo novos desafios para o diagnóstico, controle de tratamento e cuidados da atenção básica para os pacientes com TB/micobacterioses/HIV. Este caso exemplifica que a decisão por um tratamento empírico pode ser uma escolha acertada em casos com clínica e imagem compatíveis e baciloscopia ou TRM negativos.


The present study is a case report of a difficult-to-treat patient with mixed tuberculosis (TB) and non-tuberculous mycobacteria (NTM) infection. The patient has HIV, cancer and other associated diseases. TB was elucidated upon hospitalization due to hemoptysis. In the TB/NTM period, the viral load remained undetectable and CD4 ranged from 622 to 117 cells/mm3. The main symptoms were fever, cough, weight loss and sweating. The X-ray examination showed suspicion of bilateral cavitary TB; the bacilloscopy was negative and several cultures presented positive results. The following isolates were identified: Mycobacterium tuberculosis complex, Mycobacterium intracelullare/chimaera and M. fortuitum, isolated from lung samples. The TB treatment was initiated in October 2015, currently treating NTM and maintaining positive culture with identification of M. intracelullare. Antimicrobial sensitivity tests for M. intracelullare showed resistance to Isoniazid, Rifampicin, Ciprofloxacin, Ethambutol and Rifabutin. Acquired Immune Deficiency Syndrome (AIDS) therapy has increased patient survival, bringing new challenges for diagnosis, treatment control, and basic care for TB/mycobacterial/HIV patients. This case exemplifies that the decision of an empirical treatment may be the correct choice in cases with compatible clinical and imaging tests and negative smear microscopy or molecular tests.


Assuntos
Tuberculose , Coinfecção , Infecções por Mycobacterium não Tuberculosas , Neoplasias
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