RESUMO
BACKGROUND: Non-tuberculous mycobacteria (NTMs) cause diseases known as mycobacteriosis and are an important cause of morbidity and mortality. The diagnosis of pulmonary disease caused by NTM is hampered by its clinical similarity with tuberculosis (TB) and by the lack of an accurate and rapid laboratory diagnosis. OBJECTIVES: Detect DNA from NTMs directly from lung samples using real-time polymerase chain reaction (qPCR) for amplification of 16S rRNA. Additionally, DNA sequencing (hsp65 and rpoB genes) was used to identify the species of MNTs. METHODS: A total of 68 sputum samples (54 with suspected NTMs and 14 with TB) from patients treated at a referral hospital were used. FINDINGS: Of these, 27/54 (50%) were qPCR positive for NTMs and 14/14 TB patients (controls) were qPCR negative with an almost perfect concordance (Kappa of 0.93) with the Mycobacterium spp. culture. Sequencing confirmed the presence of NTM in all positive samples. The most common species was Mycobacterium gordonae (33%), followed by Mycobacterium abscessus (26%), Mycobacterium fortuitum (22%), Mycobacterium avium (15%) and Mycobacterium peregrinum (4%). MAIN CONCLUSIONS: The qPCR technique for detecting NTMs targeting 16S rRNA has the potential to detect NTMs and rapidly differentiate from Mycobacterium tuberculosis. However, it is necessary to identify the species to help in the differential diagnosis between disease and contamination, and to guide the choice of the therapeutic scheme.
Assuntos
Infecções por Mycobacterium não Tuberculosas , Mycobacterium tuberculosis , Tuberculose , Humanos , Pulmão , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium tuberculosis/genética , Micobactérias não Tuberculosas/genética , RNA Ribossômico 16S/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Introdução: Conhecer o perfil da população privada de liberdade da Penitenciária Modulada de Osório (PMO), do ponto de vista radiológico e estimar a prevalência da tuberculose ativa no presídio.Métodos: Foi realizada análise retrospectiva de 677 radiografias de tórax obtidas para rastreio de tuberculose e de dados da ficha de atendimento do setor de Radiologia no período de julho a outubro de 2019.Resultados: Foram detectadas 150 radiografias alteradas, o que representa 22% dos 677 exames. Dos 150 exames alterados, 109 (16% do total e 72% dos alterados) apresentavam lesões com características de doença granulomatosa. Dos 677 pacientes, 11,5% referiram tratamento atual ou prévio para tuberculose e estes representam 38% dos casos com radiografias alteradas. Foram detectados 50 pacientes sem história prévia de tuberculose com lesões de aspecto muito provavelmente devido a tuberculose com características de doença ativa (7,3% do total), os quais foram encaminhados para investigação como casos novos. Em relação ao questionário aplicado, não foi observada diferença significativa entre os pacientes que referiam ou negavam tosse entre os com exames normais e alterados.Conclusões: Os indivíduos privados de liberdade apresentaram alta prevalência de alterações radiológicas com aspecto sugestivo de doença granulomatosa. Estes achados permitem inferir que na Penitenciária Modulada de Osório há elevada prevalência de tuberculose, provavelmente em níveis semelhantes a outras casas prisionais do Brasil.
Introduction: To determine the radiologic profile of 'the prisoners at Osório Modular Prison and estimate the prevalence of active tuberculosis in the institution.Methods: We retrospectively analyzed 677 chest radiographs obtained for tuberculosis screening and data from the medical records of prisoners seen at the Radiology Department from July to October 2019.Results: Of 677 radiographs, 150 (22%) showed abnormalities. Of these, 109 (16% of total or 72% of abnormal radiographs) showed lesions characteristic of granulomatous disease. Of all 677 patients, 11.5% reported current or previous treatment of tuberculosis, accounting for 38% of all abnormal radiographs. Fifty patients with no previous history of tuberculosis had lesions that were most likely due to active tuberculosis (7.3% of total), and were referred for further investigation as new cases. The responses to the questionnaire revealed no significant difference between patients who reported or denied coughing when comparing those with normal vs abnormal radiographs.Conclusions: Individuals deprived of liberty had a high prevalence of radiologic abnormalities suggestive of granulomatous disease. These findings allow us to infer that there is a high prevalence of tuberculosis at Osório Modular Prison, probably at levels comparable to those of other prison facilities in Brazil.
Assuntos
Humanos , Masculino , Adulto , Adulto Jovem , Tuberculose Pulmonar/prevenção & controle , Tuberculose Pulmonar/diagnóstico por imagem , Prisioneiros/estatística & dados numéricos , Radiologia/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricosRESUMO
BACKGROUND Non-tuberculous mycobacteria (NTMs) cause diseases known as mycobacteriosis and are an important cause of morbidity and mortality. The diagnosis of pulmonary disease caused by NTM is hampered by its clinical similarity with tuberculosis (TB) and by the lack of an accurate and rapid laboratory diagnosis. OBJECTIVES Detect DNA from NTMs directly from lung samples using real-time polymerase chain reaction (qPCR) for amplification of 16S rRNA. Additionally, DNA sequencing (hsp65 and rpoB genes) was used to identify the species of MNTs. METHODS A total of 68 sputum samples (54 with suspected NTMs and 14 with TB) from patients treated at a referral hospital were used. FINDINGS Of these, 27/54 (50%) were qPCR positive for NTMs and 14/14 TB patients (controls) were qPCR negative with an almost perfect concordance (Kappa of 0.93) with the Mycobacterium spp. culture. Sequencing confirmed the presence of NTM in all positive samples. The most common species was Mycobacterium gordonae (33%), followed by Mycobacterium abscessus (26%), Mycobacterium fortuitum (22%), Mycobacterium avium (15%) and Mycobacterium peregrinum (4%). MAIN CONCLUSIONS The qPCR technique for detecting NTMs targeting 16S rRNA has the potential to detect NTMs and rapidly differentiate from Mycobacterium tuberculosis. However, it is necessary to identify the species to help in the differential diagnosis between disease and contamination, and to guide the choice of the therapeutic scheme.
RESUMO
Treatment of drug-resistant tuberculosis requires extended use of more toxic and less effective drugs and may result in retreatment cases due to failure, abandonment or disease recurrence. It is therefore important to understand the evolutionary process of drug resistance in Mycobacterium tuberculosis. We here in describe the microevolution of drug resistance in serial isolates from six previously treated patients. Drug resistance was initially investigated through phenotypic methods, followed by genotypic approaches. The use of whole-genome sequencing allowed the identification of mutations in the katG, rpsL and rpoB genes associated with drug resistance, including the detection of rare mutations in katG and mixed populations of strains. Molecular docking simulation studies of the impact of observed mutations on isoniazid binding were also performed. Whole-genome sequencing detected 266 single nucleotide polymorphisms between two isolates obtained from one patient, suggesting a case of exogenous reinfection. In conclusion, sequencing technologies can detect rare mutations related to drug resistance, identify subpopulations of resistant strains, and identify diverse populations of strains due to exogenous reinfection, thus improving tuberculosis control by guiding early implementation of appropriate clinical and therapeutic interventions.
Assuntos
Resistência a Medicamentos/genética , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Mycobacterium tuberculosis/efeitos dos fármacos , Brasil , Resistência a Medicamentos/imunologia , Estudo de Associação Genômica Ampla/métodos , Humanos , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/estatística & dados numéricos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
Genomic-based surveillance on the occurrence of drug resistance and its transmission dynamics has emerged as a powerful tool for the control of tuberculosis (TB). A whole-genome sequencing approach, phenotypic testing and clinical-epidemiological investigation were used to undertake a retrospective population-based study on drug-resistant (DR)-TB in Rio Grande do Sul, the largest state in Southern Brazil. The analysis included 305 resistant Mycobacterium tuberculosis strains sampled statewide from 2011 to 2014, and covered 75.7% of all DR-TB cases identified in this period. Lineage 4 was found to be predominant (99.3%), with high sublineage-level diversity composed mainly of 4.3.4.2 [Latin American and Mediterranean (LAM)/RD174], 4.3.3 (LAM/RD115) and 4.1.2.1 (Haarlem/RD182) sublineages. Genomic diversity was also reflected in resistance of the variants to first-line drugs. A large number of distinct resistance-conferring mutations, including variants that have not been reported previously in any other setting worldwide, and 22 isoniazid-monoresistant strains with mutations described as disputed in the rpoB gene but causing rifampicin resistance generally missed by automated phenotypic tests as BACTEC MGIT. Using a cut-off of five single nucleotide polymorphisms, the estimated recent transmission rate was 55.1%, with 168 strains grouped into 28 genomic clusters. The most worrying fact concerns multi-drug-resistant (MDR) strains, of which 73.4% were clustered. Different resistance profiles and acquisition of novel mutations intraclusters revealed important amplification of resistance in the region. This study described the diversity of M. tuberculosis strains, the basis of drug resistance, and ongoing transmission dynamics across the largest state in Southern Brazil, stressing the urgent need for MDR-TB transmission control state-wide.
Assuntos
Antibióticos Antituberculose/uso terapêutico , Proteínas de Bactérias/genética , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/genética , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antituberculosos/uso terapêutico , Brasil/epidemiologia , Perfilação da Expressão Gênica , Genoma Bacteriano/genética , Humanos , Isoniazida/uso terapêutico , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos Retrospectivos , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Sequenciamento Completo do Genoma , Adulto JovemRESUMO
PURPOSE: The establishment of candidate genetic determinants associated with tuberculosis (TB) is a challenge, considering the divergent frequencies among populations. The objective of this study was to evaluate the association between MIF - 794 CATT 5-8 polymorphism and susceptibility to TB. METHODS: Case-control study. Patients > 18 years, with pulmonary TB were included. The control group consisted of blood donors and household contacts, not relatives, healthy and > 18 years. MIF - 794 CATT 5-8 were genotyped using sequencing of PCR and capillary electrophoresis. RESULTS: 126 patients and 119 controls were included. The genotype 5/5 was more frequent among cases (15.1%) than in controls (5.9%) (p = 0.019). Cases had more frequently the allele 5 (29.4%) as compared with controls (19.3%) (p = 0.010). Prevalence of 7/X + 8/X genotypes was not different between cases and controls (p = 0.821). There was no difference between patients with alleles 7 and 8 and those with alleles 5 and 6 (p = 0.608). CONCLUSIONS: The genotype 5/5 and the allele 5 of MIF - 794 CATT 5-8 were more frequent among TB patients than in controls.
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Predisposição Genética para Doença , Fatores Inibidores da Migração de Macrófagos , Tuberculose , Estudos de Casos e Controles , Frequência do Gene , Genótipo , Humanos , Oxirredutases Intramoleculares , Fatores Inibidores da Migração de Macrófagos/genética , Repetições de Microssatélites , Polimorfismo de Nucleotídeo Único , Tuberculose/genéticaRESUMO
Drug-resistant tuberculosis (DR-TB) is major problem in the fight against TB. Multidrug resistant (MDR) TB patients have a reduced treatment success rates and for, extensively drug-resistant (XDR) TB the cure rate does not exceed 25% in many countries. To evaluate the pre-XDR-TB and XDR-TB prevalence and transmission in Rio Grande do Sul State, in southern Brazil, we performed a retrospective WGS-based analysis of 87 MDR-TB cases, aiming to identify resistance-conferring mutations and its phylogenetic distinctiveness. Using a five SNP threshold for genomic clustering, 60 strains were genomically linked within 10 clusters, including 14 likely transmission events identified by retrospective conventional epidemiological investigation. Moreover, five likely transmission events involved 17 patients deprived of liberty in the same prison establishment. Mutations associated with isoniazid and rifampicin resistance were identified respectively in 97.70% and 98.85% of MDR M.tb strains, more frequently in katG and rpoB genes. In total, we identified eight (9.19%) pre-XDR and four (4.59%) XDR M.tb strains. Resistance to ofloxacin was observed in seven (8.04%) strains, all of them presenting resistance-conferring mutations. Phenotypic resistance from capreomycin and kanamycin was found in seven (8.04%) and four (4.59%) strains respectively, but no classic mutations associated with resistance to these drugs was identified. The results put in evidence a scenario involving multiple phylogenetically distinctive clades associated with pre-XDR and XDR-TB in the largest state of southern Brazil, while stressing the potential of using WGS to predict anti-TB drug resistance and need to halt MDR-TB transmission in the region.
Assuntos
Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto , Antituberculosos/farmacologia , Brasil/epidemiologia , Farmacorresistência Bacteriana Múltipla/genética , Tuberculose Extensivamente Resistente a Medicamentos/epidemiologia , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Feminino , Variação Genética , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Repetições Minissatélites , Mutação , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Polimorfismo de Nucleotídeo Único , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Sequenciamento Completo do GenomaRESUMO
OBJECTIVE: The incidence of lung disease caused by nontuberculous mycobacteria (NTM) has been increasing worldwide. In Brazil, there are few studies about nontuberculous mycobacterial lung disease (NTMLD), and its prevalence is yet to be known. Our objective was to determine the specific etiology of the disease in the state of Rio Grande do Sul, Brazil, as well as the frequency and diversity of NTM species in our sample of patients. METHODS: This is a retrospective analysis of the medical records of patients diagnosed with NTMLD treated in a referral center located in the city of Porto Alegre, Brazil, between 2003 and 2013. RESULTS: Our sample comprised 100 patients. The most prevalent NTM species were Mycobacterium avium complex (MAC), in 35% of the cases; M. kansasii, in 17%; and M. abscessus, in 12%. A total of 85 patients had received previous treatment for tuberculosis. Associated conditions included structural abnormalities in the lungs, such as bronchiectasis, in 23% of the cases; COPD, in 17%; and immunosuppressive conditions, such as AIDS, in 24%. CONCLUSIONS: MAC and M. kansasii were the most prevalent species involved in NTMLD in the state, similarly to what occurs in other regions of Brazil. Data on regional epidemiology of NTMLD, its specific etiology, and associated conditions are essential to establish appropriate treatment, since each species requires specific regimens. Most patients with NTMLD had received previous tuberculosis treatment, which might lead to development of resistance and late diagnosis.