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1.
Eur Respir J ; 62(5)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37827576

RESUMO

BACKGROUND: Longitudinal cohort data of patients with tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are lacking. In our global study, we describe long-term outcomes of patients affected by TB and COVID-19. METHODS: We collected data from 174 centres in 31 countries on all patients affected by COVID-19 and TB between 1 March 2020 and 30 September 2022. Patients were followed-up until cure, death or end of cohort time. All patients had TB and COVID-19; for analysis purposes, deaths were attributed to TB, COVID-19 or both. Survival analysis was performed using Cox proportional risk-regression models, and the log-rank test was used to compare survival and mortality attributed to TB, COVID-19 or both. RESULTS: Overall, 788 patients with COVID-19 and TB (active or sequelae) were recruited from 31 countries, and 10.8% (n=85) died during the observation period. Survival was significantly lower among patients whose death was attributed to TB and COVID-19 versus those dying because of either TB or COVID-19 alone (p<0.001). Significant adjusted risk factors for TB mortality were higher age (hazard ratio (HR) 1.05, 95% CI 1.03-1.07), HIV infection (HR 2.29, 95% CI 1.02-5.16) and invasive ventilation (HR 4.28, 95% CI 2.34-7.83). For COVID-19 mortality, the adjusted risks were higher age (HR 1.03, 95% CI 1.02-1.04), male sex (HR 2.21, 95% CI 1.24-3.91), oxygen requirement (HR 7.93, 95% CI 3.44-18.26) and invasive ventilation (HR 2.19, 95% CI 1.36-3.53). CONCLUSIONS: In our global cohort, death was the outcome in >10% of patients with TB and COVID-19. A range of demographic and clinical predictors are associated with adverse outcomes.


Assuntos
COVID-19 , Coinfecção , Infecções por HIV , Tuberculose Miliar , Humanos , Masculino , COVID-19/complicações , Infecções por HIV/complicações , Fatores de Risco , Estudos Retrospectivos
2.
PLoS Pathog ; 16(10): e1008929, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33002063

RESUMO

The ability of Mycobacterium tuberculosis (Mtb) to persist inside host cells relies on metabolic adaptation, like the accumulation of lipid bodies (LBs) in the so-called foamy macrophages (FM), which are favorable to Mtb. The activation state of macrophages is tightly associated to different metabolic pathways, such as lipid metabolism, but whether differentiation towards FM differs between the macrophage activation profiles remains unclear. Here, we aimed to elucidate whether distinct macrophage activation states exposed to a tuberculosis-associated microenvironment or directly infected with Mtb can form FM. We showed that the triggering of signal transducer and activator of transcription 6 (STAT6) in interleukin (IL)-4-activated human macrophages (M(IL-4)) prevents FM formation induced by pleural effusion from patients with tuberculosis. In these cells, LBs are disrupted by lipolysis, and the released fatty acids enter the ß-oxidation (FAO) pathway fueling the generation of ATP in mitochondria. Accordingly, murine alveolar macrophages, which exhibit a predominant FAO metabolism, are less prone to become FM than bone marrow derived-macrophages. Interestingly, direct infection of M(IL-4) macrophages with Mtb results in the establishment of aerobic glycolytic pathway and FM formation, which could be prevented by FAO activation or inhibition of the hypoxia-inducible factor 1-alpha (HIF-1α)-induced glycolytic pathway. In conclusion, our results demonstrate that Mtb has a remarkable capacity to induce FM formation through the rewiring of metabolic pathways in human macrophages, including the STAT6-driven alternatively activated program. This study provides key insights into macrophage metabolism and pathogen subversion strategies.


Assuntos
Células Espumosas/microbiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo dos Lipídeos , Macrófagos/microbiologia , Mycobacterium tuberculosis/patogenicidade , Animais , Gotículas Lipídicas/metabolismo , Ativação de Macrófagos/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/fisiologia , Tuberculose/microbiologia
3.
Am J Respir Crit Care Med ; 204(6): 713-722, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34107231

RESUMO

Rationale: Until 2020, extensively drug-resistant tuberculosis (XDR-TB) was defined as TB with resistance to rifampicin and isoniazid (multidrug-resistant TB [MDR-TB]), any fluoroquinolone (FQ), and any second-line injectable drug (SLID). In 2019, the World Health Organization issued new recommendations for treating patients with drug-resistant TB, substantially limiting the role of SLIDs in MDR-TB treatment and thus putting the definition of XDR-TB into question. Objectives: To propose an up-to-date definition for XDR-TB. Methods: We used a large data set to assess treatment outcomes for patients with MDR-TB exposed to any type of longer regimen. We included patients with bacteriologically confirmed MDR-TB and known FQ and SLID resistance results. We performed logistic regression to estimate the adjusted odds ratios (aORs) for an unfavorable treatment outcome (failure, relapse, death, loss to follow-up), and estimates were stratified by the resistance pattern (FQ and/or SLID) and group A drug use (moxifloxacin/levofloxacin, linezolid, and/or bedaquiline). Measurements and Main Results: We included 11,666 patients with MDR-TB; 4,653 (39.9%) had an unfavorable treatment outcome. Resistance to FQs increased the odds of an unfavorable treatment outcome (aOR, 1.91; 95% confidence interval [CI], 1.63-2.23). Administration of bedaquiline and/or linezolid improved treatment outcomes regardless of resistance to FQs and/or SLIDs. Among patients with XDR-TB, compared with persons receiving no group A drug, aORs for an unfavorable outcome were 0.37 (95% CI, 0.20-0.69) with linezolid only, 0.40 (95% CI, 0.21-0.77) with bedaquiline only, and 0.21 (95% CI, 0.12-0.38) with both. Conclusions: Our study supports a new definition of XDR-TB as MDR-TB and additional resistance to FQ plus bedaquiline and/or linezolid and helps assess the adequacy of this definition for surveillance and treatment choice.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/diagnóstico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Adulto , Idoso , Bases de Dados Factuais , Diarilquinolinas/uso terapêutico , Esquema de Medicação , Farmacorresistência Bacteriana Múltipla , Quimioterapia Combinada , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Feminino , Fluoroquinolonas/uso terapêutico , Humanos , Isoniazida/uso terapêutico , Linezolida/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Rifampina/uso terapêutico , Resultado do Tratamento
4.
Lancet ; 396(10248): 402-411, 2020 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-32771107

RESUMO

BACKGROUND: HIV-infection is associated with increased mortality during multidrug-resistant tuberculosis treatment, but the extent to which the use of antiretroviral therapy (ART) and anti-tuberculosis medications modify this risk are unclear. Our objective was to evaluate how use of these treatments altered mortality risk in HIV-positive adults with multidrug-resistant tuberculosis. METHODS: We did an individual patient data meta-analysis of adults 18 years or older with confirmed or presumed multidrug-resistant tuberculosis initiating tuberculosis treatment between 1993 and 2016. Data included ART use and anti-tuberculosis medications grouped according to WHO effectiveness categories. The primary analysis compared HIV-positive with HIV-negative patients in terms of death during multidrug-resistant tuberculosis treatment, excluding those lost to follow up, and was stratified by ART use. Analyses used logistic regression after exact matching on country World Bank income classification and drug resistance and propensity-score matching on age, sex, geographic site, year of multidrug-resistant tuberculosis treatment initiation, previous tuberculosis treatment, directly observed therapy, and acid-fast-bacilli smear-positivity to obtain adjusted odds ratios (aORs) and 95% CIs. Secondary analyses were conducted among those with HIV-infection. FINDINGS: We included 11 920 multidrug-resistant tuberculosis patients. 2997 (25%) were HIV-positive and on ART, 886 (7%) were HIV-positive and not on ART, and 1749 (15%) had extensively drug-resistant tuberculosis. By use of HIV-negative patients as reference, the aOR of death was 2·4 (95% CI 2·0-2·9) for all patients with HIV-infection, 1·8 (1·5-2·2) for HIV-positive patients on ART, and 4·2 (3·0-5·9) for HIV-positive patients with no or unknown ART. Among patients with HIV, use of at least one WHO Group A drug and specific use of moxifloxacin, levofloxacin, bedaquiline, or linezolid were associated with significantly decreased odds of death. INTERPRETATION: Use of ART and more effective anti-tuberculosis drugs is associated with lower odds of death among HIV-positive patients with multidrug-resistant tuberculosis. Access to these therapies should be urgently pursued. FUNDING: American Thoracic Society, Canadian Institutes of Health Research, US Centers for Disease Control and Prevention, European Respiratory Society, Infectious Diseases Society of America.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Antituberculosos/uso terapêutico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/mortalidade , Adulto , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Fatores de Risco , Tuberculose Resistente a Múltiplos Medicamentos/complicações
5.
Emerg Infect Dis ; 26(11): 2709-2712, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917293

RESUMO

Coronavirus disease has disrupted tuberculosis services globally. Data from 33 centers in 16 countries on 5 continents showed that attendance at tuberculosis centers was lower during the first 4 months of the pandemic in 2020 than for the same period in 2019. Resources are needed to ensure tuberculosis care continuity during the pandemic.


Assuntos
Continuidade da Assistência ao Paciente/tendências , Infecções por Coronavirus/epidemiologia , Utilização de Instalações e Serviços/tendências , Saúde Global/tendências , Pneumonia Viral/epidemiologia , Tuberculose/terapia , Betacoronavirus , COVID-19 , Humanos , Pandemias , SARS-CoV-2 , Tuberculose/epidemiologia
6.
Immunol Cell Biol ; 95(8): 716-728, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28546549

RESUMO

Production of IFN-γ contributes to host defense against Mycobacterium tuberculosis (Mtb) infection. We previously demonstrated that Signaling lymphocytic activation molecule-associated protein (SAP) expression on cells from tuberculosis (TB) patients was inversely correlated with IFN-γ production. Here we first investigated the role of NK, T- and B-cell antigen (NTB-A)/SAP pathway in the regulation of Th1 response against Mtb. Upon antigen stimulation, NTB-A phosphorylation rapidly increases and afterwards modulates IFN-γ and IL-17 secretion. To sustain a healthy immune system, controlled expansion and contraction of lymphocytes, both during and after an adaptive immune response, is essential. Besides, restimulation-induced cell death (RICD) results in an essential homeostatic mechanism for precluding excess T-cell accumulation and associated immunopathology during the course of certain infections. Accordingly, we found that the NTB-A/SAP pathway was required for RICD during active tuberculosis. In low responder (LR) TB patients, impaired RICD was associated with diminished FASL levels, IL-2 production and CD25high expression after cell-restimulation. Interestingly, we next observed that SAP mediated the recruitment of the Src-related kinase FYNT, only in T cells from LR TB patients that were resistant to RICD. Together, we showed that the NTB-A/SAP pathway regulates T-cell activation and RICD during human TB. Moreover, the NTB-A/SAP/FYNT axis promotes polarization to an unfavorable Th2-phenotype.


Assuntos
Mycobacterium tuberculosis/imunologia , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo , Células Th2/imunologia , Tuberculose/imunologia , Adulto , Morte Celular , Diferenciação Celular , Células Cultivadas , Feminino , Homeostase , Humanos , Imunidade , Terapia de Imunossupressão , Interferon gama/metabolismo , Interleucina-17/metabolismo , Ativação Linfocitária , Masculino , Proteínas de Neoplasias/metabolismo , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais
7.
Eur Respir J ; 49(5)2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28529205

RESUMO

Large studies on bedaquiline used to treat multidrug-resistant (MDR-) and extensively drug-resistant tuberculosis (XDR-TB) are lacking. This study aimed to evaluate the safety and effectiveness of bedaquiline-containing regimens in a large, retrospective, observational study conducted in 25 centres and 15 countries in five continents.428 culture-confirmed MDR-TB cases were analysed (61.5% male; 22.1% HIV-positive, 45.6% XDR-TB). MDR-TB cases were admitted to hospital for a median (interquartile range (IQR)) 179 (92-280) days and exposed to bedaquiline for 168 (86-180) days. Treatment regimens included, among others, linezolid, moxifloxacin, clofazimine and carbapenems (82.0%, 58.4%, 52.6% and 15.3% of cases, respectively).Sputum smear and culture conversion rates in MDR-TB cases were 63.6% and 30.1%, respectively at 30 days, 81.1% and 56.7%, respectively at 60 days; 85.5% and 80.5%, respectively at 90 days and 88.7% and 91.2%, respectively at the end of treatment. The median (IQR) time to smear and culture conversion was 34 (30-60) days and 60 (33-90) days. Out of 247 culture-confirmed MDR-TB cases completing treatment, 71.3% achieved success (62.4% cured; 8.9% completed treatment), 13.4% died, 7.3% defaulted and 7.7% failed. Bedaquiline was interrupted due to adverse events in 5.8% of cases. A single case died, having electrocardiographic abnormalities that were probably non-bedaquiline related.Bedaquiline-containing regimens achieved high conversion and success rates under different nonexperimental conditions.


Assuntos
Antituberculosos/uso terapêutico , Diarilquinolinas/uso terapêutico , Tuberculose Extensivamente Resistente a Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Carbapenêmicos/uso terapêutico , Clofazimina/uso terapêutico , Estudos de Coortes , Quimioterapia Combinada , Feminino , Infecções por HIV/complicações , Humanos , Linezolida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Segurança do Paciente , Estudos Retrospectivos , Escarro/metabolismo , Resultado do Tratamento
8.
Am J Pathol ; 184(5): 1268-73, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24606882

RESUMO

Interferon (IFN)-γ displays a critical role in tuberculosis (TB), modulating the innate and adaptive immune responses. Previously, we reported that secretory leukocyte protease inhibitor (SLPI) is a pattern recognition receptor with anti-mycobacterial activity against Mycobacterium tuberculosis (Mtb). Herein, we determined whether IFN-γ modulated the levels of SLPI in TB patients. Plasma levels of SLPI and IFN-γ were studied in healthy donors (HDs) and TB patients. Peripheral blood mononuclear cells from HDs and patients with TB or defective IFN-γ receptor 1* were stimulated with Mtb antigen and SLPI, and IFN-γR expression levels were measured. Both SLPI and IFN-γ were significantly enhanced in plasma from those with TB compared with HDs. A direct association between SLPI levels and the severity of TB was detected. In addition, Mtb antigen stimulation decreased the SLPI produced by peripheral blood mononuclear cells from HDs, but not from TB or IFN-γR patients. Neutralization of IFN-γ reversed the inhibition of SLPI induced by Mtb antigen in HDs, but not in TB patients. Furthermore, recombinant IFN-γ was unable to modify the expression of SLPI in TB patients. Finally, IFN-γR expression was lower in TB compared with HD peripheral blood mononuclear cells. These results show that Mtb-induced IFN-γ down-modulated SLPI levels by signaling through the IFN-γR in HDs. This inhibitory mechanism was not observed in TB, probably because of the low expression of IFN-γR detected in these individuals.


Assuntos
Interferon gama/metabolismo , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Índice de Gravidade de Doença , Tuberculose/metabolismo , Tuberculose/patologia , Adulto , Estudos de Casos e Controles , Humanos , Interferon gama/sangue , Inibidor Secretado de Peptidases Leucocitárias/sangue , Tuberculose/sangue
9.
Clin Sci (Lond) ; 127(6): 391-403, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24689690

RESUMO

DTH (delayed type hypersensitivity) reactions are secondary cellular immune responses that appear 24-72 h after antigen exposure. Tuberculous pleurisy is a common manifestation of extrapulmonary TB (tuberculosis) and is considered a human model of Th1-mediated DTH. In order to identify functional cross-talk among cellular populations sited in this inflammatory microenvironment, we analysed phenotypic and functional features of human B-cells isolated from the PF (pleural fluid) of TB patients. Freshly isolated PF-B-cells displayed a lower expression of CD20, CD1d and HLA-DR, and a higher expression of CD95, CD38, CD25, CXCR3 (CXC chemokine receptor 3) and CXCR4 (CXC chemokine receptor 4) than their PB (peripheral blood) counterparts, suggesting a non-classical in situ activation. Although memory PF-T-cell frequencies were increased, the frequencies of memory PF-B-cells were not. We demonstrated that, upon stimulation with γ-irradiated M. tuberculosis, mycobacterially secreted proteins or a lectin mitogen, PF-B-cells had a strong activation and produced IL-10 by a mechanism that was dependent on bystander activation of CD19(-) PF cells. Besides, within PF cells, B-cells diminished in vitro M. tuberculosis-induced IFN (interferon)-γ production by T-cells and NK (natural killer) cells in an IL-10-dependent manner. Finally, we found that the lower the frequency of B-cells, the higher the ratio of IFN-γ/IL-10 within PF. Thus our results suggest that B-cells can regulate a human DTH reaction induced by M. tuberculosis.


Assuntos
Linfócitos B/metabolismo , Hipersensibilidade Tardia/imunologia , Interferon gama/biossíntese , Células Matadoras Naturais/metabolismo , Linfócitos T/metabolismo , Tuberculose Pleural/microbiologia , Linfócitos B/imunologia , Humanos , Imunidade Celular/imunologia , Interleucina-10/imunologia , Células Matadoras Naturais/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/imunologia , Tuberculose Pleural/imunologia
10.
Medicina (B Aires) ; 74(4): 311-4, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-25188660

RESUMO

The hyper Immunoglobulin E syndrome, also known as Job's syndrome, is a rare primary immunodeficiency, its mechanisms of inheritance maybe recessive or dominant autosomal. It is characterized by high levels of IgE, eosinophilia, skin abscesses, eczema, chronic mucocutaneous candidiasis and recurrent pulmonary infections all of which contribute to the development of pneumatoceles and bronchiectasis. The most frequently isolated bacteria is Staphylococcus aureus. Currently, despite the highest survival of patients, lymphomas and other opportunistic infections have been reported. There are few reports of patients with Mycobacterium tuberculosis infection associated with hyper IgE syndrome. Therefore it is relevant that we report a case history of a patient with pulmonary tuberculosis, presenting miliary tuberculosis and severe respiratory compromise, who responded positively to standard anti-tuberculous treatment with first line drugs.


Assuntos
Imunoglobulina E/sangue , Síndrome de Job/complicações , Tuberculose Miliar/complicações , Humanos , Isotipos de Imunoglobulinas/sangue , Masculino , Fator de Transcrição STAT3/genética , Tuberculose Miliar/tratamento farmacológico , Adulto Jovem
11.
J Infect Dis ; 207(2): 340-50, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23125442

RESUMO

Immune control of Mycobacterium tuberculosis depends on interferon γ (IFN-γ)-producing CD4(+) lymphocytes. Previous studies have shown that T cells from patients with tuberculosis produce less IFN-γ, compared with healthy donors, in response to mycobacterial antigens, although IFN-γ responses to mitogens are preserved. In this work, we found that M. tuberculosis-induced IFN-γ production by human T cells correlated with phosphorylation of the mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK), and p38. Moreover, the majority of IFN-γ-producing T cells expressed signaling lymphocyte activation molecule (SLAM), and SLAM activation further increased ERK phosphorylation. Interestingly, patients with tuberculosis had delayed activation of ERK and p38, and this was most marked in patients with the poorest IFN-γ responses (ie, low responders). Besides, SLAM signaling failed to phosphorylate ERK in low responders. Our findings suggest that activation of p38 and ERK, in part through SLAM, mediates T-cell IFN-γ production in response to M. tuberculosis, a pathway that is defective in patients with tuberculosis.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Interferon gama/biossíntese , Mycobacterium tuberculosis/imunologia , Linfócitos T/imunologia , Tuberculose Pulmonar/imunologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Antígenos CD/metabolismo , Ativação Enzimática , Humanos , Fosforilação , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Tuberculose Pulmonar/metabolismo , Tuberculose Pulmonar/microbiologia
12.
Elife ; 122024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922679

RESUMO

During tuberculosis (TB), migration of dendritic cells (DCs) from the site of infection to the draining lymph nodes is known to be impaired, hindering the rapid development of protective T-cell-mediated immunity. However, the mechanisms involved in the delayed migration of DCs during TB are still poorly defined. Here, we found that infection of DCs with Mycobacterium tuberculosis (Mtb) triggers HIF1A-mediated aerobic glycolysis in a TLR2-dependent manner, and that this metabolic profile is essential for DC migration. In particular, the lactate dehydrogenase inhibitor oxamate and the HIF1A inhibitor PX-478 abrogated Mtb-induced DC migration in vitro to the lymphoid tissue-specific chemokine CCL21, and in vivo to lymph nodes in mice. Strikingly, we found that although monocytes from TB patients are inherently biased toward glycolysis metabolism, they differentiate into poorly glycolytic and poorly migratory DCs compared with healthy subjects. Taken together, these data suggest that because of their preexisting glycolytic state, circulating monocytes from TB patients are refractory to differentiation into migratory DCs, which may explain the delayed migration of these cells during the disease and opens avenues for host-directed therapies for TB.


Assuntos
Movimento Celular , Células Dendríticas , Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia , Monócitos , Mycobacterium tuberculosis , Tuberculose , Células Dendríticas/metabolismo , Células Dendríticas/imunologia , Monócitos/metabolismo , Monócitos/imunologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mycobacterium tuberculosis/imunologia , Animais , Tuberculose/imunologia , Tuberculose/metabolismo , Tuberculose/microbiologia , Camundongos , Receptor 2 Toll-Like/metabolismo , Camundongos Endogâmicos C57BL , Feminino
13.
Medicina (B Aires) ; 83(5): 799-803, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37870338

RESUMO

Mixed infection by Mycobacterium tuberculosis (Mtb) consists in the simultaneous coexistence in the same patient of two different strains of Mtb or 2 different variants of the same strain. When one of the variants selects for resistance mutations, it is called monoclonal heteroresistance (HTR); if there are 2 different strains, one sensitive and one resistant (or with different resistance patterns), it is called polyclonal HTR. Three cases of HIV/AIDS patients are presented, all with repeated treatment adherence problems, in whom monoclonal HTR was diagnosed through Mtb complete genomic sequentiation with the coexistence of two variants of the same strain isolated from samples from lung and lymph nodes, with different resistance profiles in each case. It is important to consider the possibility of HTR, especially in patients with multiple previous therapeutic attempts and high bacillary populations, such as in advanced AIDS, since this situation potentially compromises treatment results by coexisting sensitive and resistant variants of a strain (or strains).


Se considera infección mixta por Mycobacterium tuberculosis (Mtb) a la coexistencia en forma simultánea y en un mismo paciente de 2 cepas diferentes de Mtb o 2 variantes distintas de la misma cepa. Cuando una de las variantes selecciona mutaciones de resistencia, se denomina heterorresistencia (HTR) monoclonal; en caso de que sean 2 cepas diferentes, una sensible y una resistente (o cepas con diferentes patrones de resistencia), se denomina HTR policlonal. Se presentan 3 pacientes, HIV/sida, todos con reiterados problemas de adherencia al tratamiento, en los cuales a través de la secuenciación genómica completa de Mtb se diagnosticó HTR monoclonal con coexistencia de 2 variantes de la misma cepa aisladas de muestras de pulmón y ganglios linfáticos, con diferentes perfiles de resistencia en cada uno de los casos. Es importante pensar en la posibilidad de HTR, principalmente en pacientes con múltiples intentos terapéuticos previos y altas poblaciones bacilares, como en el sida avanzado, dado que esta situación compromete potencialmente los resultados del tratamiento al coexistir cepas o variantes de cepas sensibles y resistentes.


Assuntos
Síndrome da Imunodeficiência Adquirida , Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Mutação , Antituberculosos/uso terapêutico
14.
Front Cell Infect Microbiol ; 13: 1080100, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36743307

RESUMO

Introduction: Tuberculosis (TB) is now the 2nd leading infectious killer after COVID-19 and the 13th leading cause of death worldwide. Moreover, TB is a lethal combination for HIV-patients. Th1 responses and particularly IFN-γ are crucial for immune protection against Mycobacterium tuberculosis infection. Many gene variants for IFNG that confer susceptibility to TB have been described in multiple ethnic populations. Likewise, some epigenetic modifications have been evaluated, being CpG methylation the major epigenetic mark that makes chromatin inaccessible to transcription factors, thus avoiding the initiation of IFNG transcription. Methods: We evaluated both genetic and epigenetic changes involved in IFN-γ production and TB susceptibility in Argentine population. Amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) was performed for the IFN-γ +874 A/T polymorphism (rs2430561) genotyping in 199 healthy donors (HD) and 173 tuberculosis (TB) patients. IFN-γ levels from M. tuberculosis-stimulated PBMCs were measured by ELISA. The methylation status at the -53 CpG site of the IFNG promoter in individuals with latent infection (LTBI), TB and HD was determine by pyrosequencing. Results: Using a case-control study, we found that A allele and, consequently, AA genotype were overrepresented in patients with active disease. Moreover, HD carrying T allele (AT or TT genotype) evidenced an augmented IFN-γ secretion compared to TB patients. Codominance was the genetic model that best fits our results according to the Akaike information criterion (AIC). In addition, increased methylation levels at the -53 CpG site in the IFN-γ promoter were observed in whole blood of patients with active TB compared to LTBI individuals. Discussion: IFN-γ is regulated by genetic variants and epigenetic modifications during TB. Besides, AA genotype of the rs2430561 single nucleotide polymorphism could be considered as a potential TB susceptibility genetic biomarker in Argentina and the methylation of the -53 CpG site could result in a useful predictor of TB reactivation.


Assuntos
COVID-19 , Interferon gama , Mycobacterium tuberculosis , Tuberculose , Humanos , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Interferon gama/genética , Polimorfismo de Nucleotídeo Único , Tuberculose/genética
15.
Emerg Infect Dis ; 18(11): 1802-10, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23092584

RESUMO

During 2003-2009, the National Tuberculosis (TB) Laboratory Network in Argentina gave 830 patients a new diagnosis of multidrug-resistant (MDR) TB and 53 a diagnosis of extensively drug- resistant (XDR) TB. HIV co-infection was involved in nearly one third of these cases. Strain genotyping showed that 7 major clusters gathered 56% of patients within restricted geographic areas. The 3 largest clusters corresponded to epidemic MDR TB strains that have been undergoing transmission for >10 years. The indigenous M strain accounted for 29% and 40% of MDR and XDR TB cases, respectively. Drug-resistant TB trends in Argentina are driven by spread of a few strains in hotspots where the rate of HIV infection is high. To curb transmission, the national TB program is focusing stringent interventions in these areas by strengthening infection control in large hospitals and prisons, expediting drug resistance detection, and streamlining information-sharing systems between HIV and TB programs.


Assuntos
Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Adolescente , Adulto , Idoso , Argentina/epidemiologia , Criança , Análise por Conglomerados , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/classificação , Adulto Jovem
16.
PLoS Med ; 9(8): e1001300, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22952439

RESUMO

BACKGROUND: Treatment of multidrug resistant tuberculosis (MDR-TB) is lengthy, toxic, expensive, and has generally poor outcomes. We undertook an individual patient data meta-analysis to assess the impact on outcomes of the type, number, and duration of drugs used to treat MDR-TB. METHODS AND FINDINGS: Three recent systematic reviews were used to identify studies reporting treatment outcomes of microbiologically confirmed MDR-TB. Study authors were contacted to solicit individual patient data including clinical characteristics, treatment given, and outcomes. Random effects multivariable logistic meta-regression was used to estimate adjusted odds of treatment success. Adequate treatment and outcome data were provided for 9,153 patients with MDR-TB from 32 observational studies. Treatment success, compared to failure/relapse, was associated with use of: later generation quinolones, (adjusted odds ratio [aOR]: 2.5 [95% CI 1.1-6.0]), ofloxacin (aOR: 2.5 [1.6-3.9]), ethionamide or prothionamide (aOR: 1.7 [1.3-2.3]), use of four or more likely effective drugs in the initial intensive phase (aOR: 2.3 [1.3-3.9]), and three or more likely effective drugs in the continuation phase (aOR: 2.7 [1.7-4.1]). Similar results were seen for the association of treatment success compared to failure/relapse or death: later generation quinolones, (aOR: 2.7 [1.7-4.3]), ofloxacin (aOR: 2.3 [1.3-3.8]), ethionamide or prothionamide (aOR: 1.7 [1.4-2.1]), use of four or more likely effective drugs in the initial intensive phase (aOR: 2.7 [1.9-3.9]), and three or more likely effective drugs in the continuation phase (aOR: 4.5 [3.4-6.0]). CONCLUSIONS: In this individual patient data meta-analysis of observational data, improved MDR-TB treatment success and survival were associated with use of certain fluoroquinolones, ethionamide, or prothionamide, and greater total number of effective drugs. However, randomized trials are urgently needed to optimize MDR-TB treatment. Please see later in the article for the Editors' Summary.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Adulto , Intervalos de Confiança , Feminino , Humanos , Masculino , Razão de Chances , Recidiva , Falha de Tratamento
17.
Medicina (B Aires) ; 82(6): 959-962, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-36571538

RESUMO

A case of a 20-year-old man with multilevel non-contiguous tuberculous spondylitis (cervical, dorsal 6, dorsal 10 and lumbar) is presented. In the context of disseminated tuberculosis in an HIV-negative patient with serious compromise of his general condition and multiple locations of the disease, some of these with fistulas that secreted caseum. The acute paraplegia led, considering the sensory level at dorsal 6, to a first urgent decompression surgery via the posterior approach. A scheduled surgery was then performed, first in the cervical region via the anterior approach, with corpectomy, placement of a vertebral body replacement plus autologous graft and plate with screws. Subsequently, dislocation of dorsal level 6 was evidenced backwards, compressing the spinal cord and, given the mechanical instability, a third surgical stage was indicated by posterior approach, which included reduction, decompression and fixation, resolving the three levels by posterior approach with bars and screws. The surgical, medical and physiotherapy treatment of this rare form of Pott's disease was successful, with recovery of his mechanical stability and progressive recovery of his neurological status. The surgical, medical and physiotherapy treatment of this rare form of Pott's disease was successful, with recovery of his mechanical stability and progressive recovery of his neurological status.


Se presenta el caso de un varón de 20 años con espondilitis tuberculosa multinivel no contigua (cervical, dorsal 6, dorsal 10 y lumbar). Se trata de un paciente HIV negativo con tuberculosis diseminada con grave compromiso de su estado general y múltiples localizaciones de la enfermedad. Algunas tenían fistulas que secretaban caseum. El paciente presentó paraplejía aguda que requirió, teniendo en cuenta el nivel sensitivo a nivel dorsal 6, una primera cirugía urgente de descompresión por vía posterior. Luego se efectuó la cirugía programada. En primera instancia, la región cervical por vía anterior, con corporectomía, colocación de reemplazo de cuerpo vertebral más injerto autólogo y placa con tornillos. Posteriormente se evidenció luxación del nivel dorsal 6 hacia atrás comprimiendo la médula espinal y, dada la inestabilidad mecánica, se indicó un tercer tiempo quirúrgico por vía posterior que comprendió reducción, descompresión y fijación, resolviendo los tres niveles por vía posterior con barras y tornillos. El tratamiento quirúrgico, médico y kinésico de esta forma poco frecuente del mal de Pott fue exitoso, con recuperación de su estabilidad mecánica y progresiva recuperación de su estado neurológico.


Assuntos
Tuberculose da Coluna Vertebral , Masculino , Humanos , Adulto Jovem , Adulto , Tuberculose da Coluna Vertebral/complicações , Tuberculose da Coluna Vertebral/diagnóstico por imagem , Tuberculose da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia
18.
Medicina (B Aires) ; 82(1): 117-129, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35037870

RESUMO

Since 2018, important changes in the treatment of drug-resistant tuberculosis have been produced in the light of new evidence. The discovery of new anti-tuberculosis drugs, such as bedaquiline and nitroimidazopirane derivatives, as well as the use of repurposed drugs, led to international organizations to recommend new, totally oral, treatment regimens for mono-resistant and multidrug-resistant tuberculosis, leaving aside the prolonged use of injectables, with their inherent toxicity and discomfort. Some definitions of drug-resistant tuberculosis have changed. The duration of treatment is also under review, leading some new regimens under study, such as BPaL (bedaquiline, pretomanid and linezolid), to a duration similar to that for treating susceptible tuberculosis. In this narrative review, we describe the new definitions, some basic diagnostic aspects, the pharmacological aspects, and the new classification of drugs to be used in the treatment of drug-resistant tuberculosis as well as the currently proposed schemes to treat it available within the Argentinean context. Finally, we include a brief review of ongoing clinical trials on new shortened treatments.


Desde 2018 han surgido a la luz de la evidencia importantes cambios en el tratamiento de la tuberculosis drogorresistente. El descubrimiento de nuevas drogas antituberculosis, como la bedaquilina y los derivados de nitroimidazopiranos, así como la utilización de drogas repropuestas, llevó a la recomendación de organismos internacionales de nuevos esquemas de tratamiento de la tuberculosis monorresistente y multidrogorresistente que son totalmente orales y así dejan de lado el uso prolongado de inyectables, con su inherente toxicidad e incomodidad. Algunas de las definiciones de tuberculosis drogorresistente han cambiado. También está en revisión el tiempo de su tratamiento y con algunos nuevos esquemas en estudio, como el BpaL (bedaquilina, pretomanid y linezolid), se ha logrado una duración similar a la del tratamiento de la tuberculosis pansensible. En esta revisión bibliográfica narrativa describimos las nuevas definiciones, algunos aspectos diagnósticos básicos, los aspectos farmacológicos y la nueva clasificación de las drogas a utilizar en el tratamiento de la tuberculosis drogorresistente, así como los esquemas actualmente propuestos para tratarla, contextualizados con la realidad nacional. Finalizamos con una breve reseña de los estudios clínicos en curso de nuevos esquemas acortados de tratamiento.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/uso terapêutico , Criança , Humanos , Linezolida/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
19.
Front Cell Infect Microbiol ; 12: 841741, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360105

RESUMO

Alterations of myeloid cell populations have been reported in patients with tuberculosis (TB). In this work, we studied the relationship between myeloid-derived suppressor cells (MDSC) and monocytes subsets with the immunological responsiveness of TB patients. Individuals with active TB were classified as low responders (LR-TB) or high responders (HR-TB) according to their T cell responses against a cell lysate of Mycobacterium tuberculosis (Mtb-Ag). Thus, LR-TB, individuals with severe disease, display a weaker immune response to Mtb compare to HR-TB, subjects with strong immunity against the bacteria. We observed that LR-TB presented higher percentages of CD16 positive monocytes as compared to HR-TB and healthy donors. Moreover, monocyte-like (M-MDSC) and polymorphonuclear-like (PMN-MDSC) MDSC were increased in patients and the proportion of M-MDSC inversely correlated with IFN-γ levels released after Mtb-Ag stimulation in HR-TB. We also found that LR-TB displayed the highest percentages of circulating M-MDSC. These results demonstrate that CD16 positive monocytes and M-MDSC frequencies could be used as another immunological classification parameter. Interestingly, in LR-TB, frequencies of CD16 positive monocytes and M-MDSC were restored after only three weeks of anti-TB treatment. Together, our findings show a link between the immunological status of TB patients and the levels of different circulating myeloid cell populations.


Assuntos
Mycobacterium tuberculosis , Células Supressoras Mieloides , Tuberculose , Humanos , Monócitos , Células Mieloides
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