RESUMO
BACKGROUND: . The Mycobacterium tuberculosis Beijing genotype is globally spread lineage with important medical properties that however vary among its subtypes. M. tuberculosis Beijing 14717-15-cluster was recently discovered as both multidrug-resistant, hypervirulent, and highly-lethal strain circulating in the Far Eastern region of Russia. Here, we aimed to analyze its pathogenomic features and phylogeographic pattern. RESULTS: . The study collection included M. tuberculosis DNA collected between 1996 and 2020 in different world regions. The bacterial DNA was subjected to genotyping and whole genome sequencing followed by bioinformatics and phylogenetic analysis. The PCR-based assay to detect specific SNPs of the Beijing 14717-15-cluster was developed and used for its screening in the global collections. Phylogenomic and phylogeographic analysis confirmed endemic prevalence of the Beijing 14717-15-cluster in the Asian part of Russia, and distant common ancestor with isolates from Korea (> 115 SNPs). The Beijing 14717-15-cluster isolates had two common resistance mutations RpsL Lys88Arg and KatG Ser315Thr and belonged to spoligotype SIT269. The Russian isolates of this cluster were from the Asian Russia while 4 isolates were from the Netherlands and Spain. The cluster-specific SNPs that significantly affect the protein function were identified in silico in genes within different categories (lipid metabolism, regulatory proteins, intermediary metabolism and respiration, PE/PPE, cell wall and cell processes). CONCLUSIONS: . We developed a simple method based on real-time PCR to detect clinically significant MDR and hypervirulent Beijing 14717-15-cluster. Most of the identified cluster-specific mutations were previously unreported and could potentially be associated with increased pathogenic properties of this hypervirulent M. tuberculosis strain. Further experimental study to assess the pathobiological role of these mutations is warranted.
Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Filogeografia , Filogenia , Genótipo , Tuberculose/epidemiologia , Tuberculose/microbiologiaRESUMO
Candida auris is a novel and major fungal pathogen that has triggered several outbreaks in the last decade. The few drugs available to treat fungal diseases, the fact that this yeast has a high rate of multidrug resistance and the occurrence of misleading identifications, and the ability of forming biofilms (naturally more resistant to drugs) has made treatments of C. auris infections highly difficult. This review intends to quickly illustrate the main issues in C. auris identification, available treatments and the associated mechanisms of resistance, and the novel and alternative treatment and drugs (natural and synthetic) that have been recently reported.
Assuntos
Antifúngicos/farmacologia , Candida/isolamento & purificação , Candidíase/tratamento farmacológico , Farmacorresistência Fúngica/efeitos dos fármacos , Antifúngicos/química , Antifúngicos/uso terapêutico , Azóis/farmacologia , Candida/efeitos dos fármacos , Candidíase/microbiologia , Quimioterapia Combinada , Equinocandinas/farmacologia , Humanos , Micologia/métodos , Polienos/farmacologia , Falha de TratamentoRESUMO
BACKGROUND: Maintaining the quality of clinical specimens for tuberculosis (TB) testing is a major challenge in many high TB burden-limited resources countries. Sample referral systems in low and middle income countries are often weak and the maintenance of the cold-chain challenging and very costly for TB programs. The development of transport media allowing the preservation of samples without refrigeration is critical for increasing access to TB diagnostic services and for reducing the costs related to testing. METHODS: We evaluated the performance of OMNIgene-SPUTUM (OM-S) reagent for the maintenance of Mycobacterium tuberculosis (MTB) viability in sputum samples in the absence of refrigeration and its capacity to stabilize nucleic acid for molecular testing. A total of 329 sputum specimens from presumptive TB cases collected at the National Reference Laboratory in Tirana, Albania, were either decontaminated by a conventional method or processed with OM-S reagent and stored at room temperature. Samples in OM-S were shipped to the Supranational Reference Laboratory in Milan, Italy, at various times and processed for liquid culture. RESULTS: Our data show that OM-S maintains MTB viability for at least three weeks in the absence of refrigeration and improves the quality of culture resulting in a contamination rate lower than 0.5%. However, a significant delay in the time to culture positivity was observed for samples stored for more than two weeks in OM-S. CONCLUSIONS: Overall, OM-S offers multiple benefits both at laboratory and TB national program level by increasing the availability to quality diagnostics, promoting access to health care services and strengthening TB patient care especially in hard to reach populations.
Assuntos
Mycobacterium tuberculosis , Manejo de Espécimes/métodos , Escarro/microbiologia , Tuberculose/microbiologia , Humanos , Indicadores e Reagentes , Estudos Prospectivos , Sensibilidade e Especificidade , Temperatura , Tuberculose/diagnósticoRESUMO
This study shows that the addition of a consensus 4-locus set of hypervariable mycobacterial interspersed repetitive-unit-variable-number tandem repeat (MIRU-VNTR) loci to the spoligotyping-24-locus MIRU-VNTR typing strategy is a well-standardized approach that can contribute to an improvement of the true cluster definition while retaining high typeability in non-Beijing strains.
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Loci Gênicos , Repetições Minissatélites , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , Tuberculose/microbiologia , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Marcadores Genéticos , Genótipo , Humanos , Epidemiologia Molecular , Polimorfismo de Fragmento de Restrição , Kit de Reagentes para DiagnósticoRESUMO
Members of Bacillota and Pseudomonadota phyla are frequently considered bacterial infectious agents in humans. As part of a large sequencing project of clinically relevant pathogens, we hybrid-assembled complete genomes of Cytobacillus, Domibacillus, Enterobacter, Neisseria, Pseudomonas, and Streptococcus species isolated from clinical specimens.
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The Two Weeks in the World research project has resulted in a dataset of 3087 clinically relevant bacterial genomes with pertaining metadata, collected from 59 diagnostic units in 35 countries around the world during 2020. A relational database is available with metadata and summary data from selected bioinformatic analysis, such as species prediction and identification of acquired resistance genes.
Assuntos
Bactérias , Genoma Bacteriano , Bactérias/genética , Biologia Computacional , Bases de Dados Factuais , MetadadosRESUMO
Ancient sublineage of the Mycobacterium tuberculosis Beijing genotype is endemic and prevalent in East Asia and rare in other world regions. While these strains are mainly drug susceptible, we recently identified a novel clonal group Beijing 1071-32 within this sublineage emerging in Siberia, Russia and present in other Russian regions. This cluster included only multi/extensive drug resistant (MDR/XDR) isolates. Based on the phylogenetic analysis of the available WGS data, we identified three synonymous SNPs in the genes Rv0144, Rv0373c, and Rv0334 that were specific for the Beijing 1071-32-cluster and developed a real-time PCR assay for their detection. Analysis of the 2375 genetically diverse M. tuberculosis isolates collected between 1996 and 2020 in different locations (European and Asian parts of Russia, former Soviet Union countries, Albania, Greece, China, Vietnam, Japan and Brazil), confirmed 100% specificity and sensitivity of this real-time PCR assay. Moreover, the epidemiological importance of this strain and the newly developed screening assay is further stressed by the fact that all identified Beijing 1071-32 isolates were found to exhibit MDR genotypic profiles with concomitant resistance to additional first-line drugs due to a characteristic signature of six mutations in rpoB450, rpoC485, katG315, katG335, rpsL43 and embB497. In conclusion, this study provides a set of three concordant SNPs for the detection and screening of Beijing 1071-32 isolates along with a validated real-time PCR assay easily deployable across multiple settings for the epidemiological tracking of this significant MDR cluster.
Assuntos
Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Pequim/epidemiologia , DNA Bacteriano/análise , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Humanos , Epidemiologia Molecular , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Polimorfismo de Nucleotídeo Único , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologiaRESUMO
Isolation of metallo-ß-lactamase-producing, carbapenem-resistant, Pseudomonas aeruginosa strains is increasingly being documented worldwide; their presence constitutes a public health threat. Here, we report draft genome sequences of two New Delhi metallo-ß-lactamase-1-producing, multidrug-resistant, P. aeruginosa strains of sequence type 235 that were isolated from the surgical wound of two patients hospitalized in the same ward.
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Albania is a Balkan country with moderate to low incidence of tuberculosis (TB) and very low prevalence of drug resistant TB. Here, we analyzed a country-wide multi-year Mycobacterium tuberculosis collection in order to detect possible dynamic trends of TB in Albania, with a focus on drug resistance and endemic/epidemic clones. In total, 743 isolates collected in 2007 to 2011 were divided into 107 spoligotypes and 351 MIRU-types. Based on the MIRU-VNTR phylogenetic analysis, the isolates were assigned to the following lineages/families: animal ecotypes (5 M. bovis and 2 M. caprae isolates), Lineage 2 (5 Beijing isolates), Lineage 3 (1 CAS-Delhi isolate) and, mostly and overwhelmingly, Lineage 4 (Cameroon, Uganda, Ghana and related; NEW-1-related; Ural, Haarlem, LAM, S, TUR; and unclassified isolates). Most of the isolates (452/743) were intermediately located on the global VNTR tree and did not cluster with any reference profile; they were distantly related to different families within Lineage 4 and we designated them as "unclassified L4" isolates. The significantly higher proportion of drug resistance was observed in (i) Beijing genotype compared to all other isolates (60%, P = .008), (ii) "unclassified L4" compared to all other isolates (13.9%, P = .04) and (iii) SIT2936 compared to other "unclassified L4" (34.3%, P = .0006). Analysis of the yearly collections revealed (i) some decrease of the large heterogeneous "unclassified L4" from 65% to 57%; (ii) steadily increasing gradient of LAM from 3.4 to 13.3%; (iii) stable prevalence of Haarlem (15-20%); and (iv) decrease of TUR with only 1.1% in 2011. Most of the LAM (33/49) and Beijing (3/5) isolates belonged to the VNTR types specific for Russia and former Soviet Union countries. To conclude, our results highlight a peculiar nature of M. tuberculosis population in Albania that is dominated by local and unclassified genotypes within Lineage 4, and also features European genotypes and epidemically relevant clones originating from the former Soviet Union countries. At the same time, these imported clones remain drug susceptible and prevalence of drug resistance on a whole is low.
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Mycobacterium tuberculosis/genética , Tuberculose/epidemiologia , Tuberculose/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Albânia/epidemiologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana/genética , Feminino , Genótipo , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Epidemiologia Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/microbiologia , Adulto JovemRESUMO
Mycobacterial interspersed repetitive units variable number tandem repeat (MIRU-VNTR) typing of Mycobacterium tuberculosis complex (MTBC) isolates, based on 24 loci, is still widely used as the standard for routine molecular surveillance of tuberculosis (TB). QIAxcel system is proposed as an affordable tool that could replace conventional gel electrophoresis and provide high concordance with the reference methods regarding MIRU-VNTR typing of MTBC. We aimed to evaluate the QIAxcel accuracy for allele calling of MIRU-VNTR loci in two regional reference laboratories. A total of 173 DNA were used for the study. Results obtained with QIAxcel were compared to the reference results obtained with an ABI 3730 DNA analyzer. In Albania, the overall agreement with the reference method was 97.92%. A complete agreement result was obtained for 17 loci. In Tunisia, the overall agreement with the reference method was 98.95%. A complete agreement result was obtained for 17 loci. Overall agreement in both centers was 98.43%. In our opinion, use of QIAxcel technology has the potential to be reliable, given an optimized algorithm. Inaccuracies in sizing of long fragments should be solved, especially regarding locus 4052.
RESUMO
We characterized a set of 100 Mycobacterium tuberculosis complex clinical isolates from tuberculosis (TB) patients in Albania, typing them with a 24-locus variable-number tandem-repeat-spoligotyping scheme. Depending on the cluster definition, 43 to 49 patients were distributed into 15 to 16 clusters which were likely to be epidemiologically linked, indicative of a recent transmission rate of 28 to 34%. This result suggests that TB is under control in Albania. However, two multidrug-resistant (MDR) Beijing genotypes harboring the same S531A mutation on the rpoB gene were also found, suggesting a potential recent transmission of MDR TB. Three brand new genotypes, Albania-1 to Albania-3, are also described.
Assuntos
Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Variação Genética , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/epidemiologia , Tuberculose/microbiologia , Albânia/epidemiologia , Análise por Conglomerados , Impressões Digitais de DNA/métodos , RNA Polimerases Dirigidas por DNA/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Epidemiologia Molecular , Mutação de Sentido Incorreto , Mycobacterium tuberculosis/genéticaRESUMO
OBJECTIVES: Carbapenemases represent a public health threat, as they can spread through horizontal gene transfer and cause outbreaks. New Delhi metallo-ß-lactamase-1 (NDM-1) is a metallo-ß-lactamase that has spread rapidly in the last decade, causing worldwide alarm. This study aimed to describe the first isolate of NDM-1-producing and extensively drug resistant Klebsiella pneumoniae in Albania, its clinical context and genetic characterization. METHODS: Strain was isolated from both oral and rectal intensive care unit admission screening swabs of a 70-year-old male patient with no history of international travel in the previous 6 months. Sequencing was performed by Illumina NextSeq500 platform, with a paired-end run of 2 by 150bp, after Nextera XT paired-end library preparation. Sequencing reads were assembled using SPAdes Genome (version 3.6.1) with accurate de novo settings. The assembled contigs were uploaded into the online tools: BIGSdb-Kp, ResFinder and PlasmidFinder. RESULTS: Isolate was resistant to all tested antibiotics but tigecycline and trimethoprim-sulfamethoxazole. Sequencing revealed the presence of acquired resistance genes conferring resistance to ß-lactams (blaNDM-1, blaCMY-6, blaCTX-M-15and blaSHV-28), aminoglycosides (rmtC, aac(6')-Ib3), fluoroquinolones (oqxA, oqxB, aac(6')-Ib-cr), fosfomycin (fosA) and sulfonamides (sul1). The blaNDM-1 gene was located on an IncA/C2 plasmid. Plasmid mediated mcr-1 to mcr-8 genes were absent in both isolates. Resistance to colistin was due to an amino acid substitution (Thr157Pro) in PmrB protein. CONCLUSIONS: NDM-1-producing Enterobacteriaceae are spreading in the Balkans. Identification of NDM-1-producing and extensively drug resistant K. pneumoniae ST15 in Albania is a cause for serious concern. There should be a continuous national and Balkan multinational surveillance of blaNDM-1-carrying isolates.
Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Trato Gastrointestinal/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , beta-Lactamases , Idoso , Albânia , Técnicas de Tipagem Bacteriana , Farmacorresistência Bacteriana Múltipla , Humanos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/isolamento & purificação , Estudos Longitudinais , Masculino , Testes de Sensibilidade Microbiana , Boca/microbiologia , Tipagem de Sequências Multilocus , Plasmídeos/genética , Reto/microbiologia , Análise de Sequência de DNARESUMO
The aims of the present study were to implement a microbead-based 'spoligotyping' technique and to evaluate improvements by the addition of a panel of 25 extra spacers that we expected to provide an increased resolution on principal genetic group 1 (PGG 1) strains. We confirmed the high sensitivity and reproducibility of the classical technique using the 43 spacer panel and we obtained perfect agreement between the membrane-based and the microbead-based techniques. We further demonstrated an increase in the discriminative power of an extended 68 spacer format for differentiation of PGG 1 clinical isolates, in particular for the East African-Indian clade. Finally, we define a limited yet highly informative reduced 10 spacer panel set which could offer a more cost-effective option for implementation in resource-limited countries and that could decrease the need for additional VNTR (variable number of tandem repeats) genotyping work in molecular epidemiological studies. We also present an economic analysis comparing membrane-based and microbead-based techniques.