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1.
Yonsei Med J ; 61(9): 789-796, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882763

RESUMO

PURPOSE: The prevalence of Mycobacterium tuberculosis (M. tb) and the status of M. bovis BCG vaccination may affect host immune responses to M. tb antigens. Understanding of the predominant local M. tb strain and immune signatures induced by its strain-specific antigens may contribute to an improved diagnosis of tuberculosis (TB). The aim of this study was to determine immune responses to M. tb antigen which was identified from the hyper-virulent Beijing/K strain in South Korea. MATERIALS AND METHODS: Pulmonary TB patients (n=52) and healthy subjects (n=92) including individuals with latent TB infection (n=31) were recruited, and QuantiFERON-TB Gold In-Tube tests were performed. The Beijing/K-antigen specific immune signatures were examined by diluted whole blood assays and multiplex bead arrays in a setting where nationwide BCG vaccination is employed. RESULTS: Statistical analyses demonstrated that three [C-X-C motif chemokine (CXCL10), interleukin (IL)-6, interferon (IFN)-α] of 17 cytokines/chemokines distinguished active cases from healthy controls following stimulation with the Beijing/K-specific antigen. IFN-α also differentiated between active diseases and latent TB infection (p<0.01), and the detection rate of TB was dramatically increased in combination with IL-6 and CXCL10 at the highest levels of specificity (95-100%). CONCLUSION: Our data indicate that immune signatures to the M. tb Beijing/K-specific antigen can provide useful information for improved TB diagnostics. The antigen may be developed as a diagnostic marker or a vaccine candidate, particularly in regions where the M. tb Beijing/K strain is endemic.


Assuntos
Tuberculose Latente/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Antígenos de Bactérias/sangue , Antígenos de Bactérias/genética , Antígenos de Superfície/sangue , Antígenos de Superfície/genética , Proteínas de Bactérias , Pequim , Estudos de Casos e Controles , Citocinas/sangue , Feminino , Humanos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/metabolismo , República da Coreia , Sensibilidade e Especificidade
2.
Pediatrics ; 146(4)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32994177

RESUMO

BACKGROUND: New guidelines support using interferon-γ release assays (IGRAs) in children ≥2 years for diagnosis of latent tuberculosis infection (LTBI). However, lack of experience in young children and concern that IGRAs are less sensitive than tuberculin skin tests (TSTs) limit their use. Our aim was to identify active tuberculosis (TB) cases among high risk children <5 years and tested for LTBI with an IGRA. METHODS: . Retrospective review of domestic TB screening data from California's Refugee Health Electronic Information System for children <5 years old who resettled in California between October, 2013 and December, 2016. Children were crossmatched with the California TB registry to identify cases of TB disease between October 2013 and December 2018. RESULTS: A total of 3371 children <5 years were identified; the majority were born in countries with high TB incidence (>150 cases per 100 000). Half received IGRAs (n = 1878; 56%), a quarter received TSTs (n = 811; 24%); 1.4% of children were IGRA-positive (n = 26) and 13% were TST-positive (n = 106). Twenty-two IGRA results were indeterminate (1.2%). Sixteen children had both tests; 9 were discrepant (positive TST with negative IGRA). No cases of TB disease were identified during 10 797 person-years of follow-up. CONCLUSIONS: IGRA positivity was less than TST positivity in high risk children <5 years old. Despite fewer LTBI diagnoses in the IGRA-tested population, no cases of TB disease among children who tested negative were identified, suggesting IGRA is valuable tool for identifying LTBI in this population.


Assuntos
Testes de Liberação de Interferon-gama/estatística & dados numéricos , Tuberculose Latente/diagnóstico , Refugiados/estatística & dados numéricos , Teste Tuberculínico/estatística & dados numéricos , California/epidemiologia , Pré-Escolar , Feminino , Humanos , Tuberculose Latente/epidemiologia , Masculino , Estudos Retrospectivos
3.
BMC Infect Dis ; 20(1): 677, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32942991

RESUMO

BACKGROUND: Approximately 80% - 90% of individuals infected with latent Mycobacterium tuberculosis (Mtb) remain protected throughout their life-span. The release of unique, latent-phase antigens are known to have a protective role in the immune response against Mtb. Although the BCG vaccine has been administered for nine decades to provide immunity against Mtb, the number of TB cases continues to rise, thereby raising doubts on BCG vaccine efficacy. The shortcomings of BCG have been associated with inadequate processing and presentation of its antigens, an inability to optimally activate T cells against Mtb, and generation of regulatory T cells. Furthermore, BCG vaccination lacks the ability to eliminate latent Mtb infection. With these facts in mind, we selected six immunodominant CD4 and CD8 T cell epitopes of Mtb expressed during latent, acute, and chronic stages of infection and engineered a multi-epitope-based DNA vaccine (C6). RESULT: BALB/c mice vaccinated with the C6 construct along with a BCG vaccine exhibited an expansion of both CD4 and CD8 T cell memory populations and augmented IFN-γ and TNF-α cytokine release. Furthermore, enhancement of dendritic cell and macrophage activation was noted. Consequently, illustrating the elicitation of immunity that helps in the protection against Mtb infection; which was evident by a significant reduction in the Mtb burden in the lungs and spleen of C6 + BCG administered animals. CONCLUSION: Overall, the results suggest that a C6 + BCG vaccination approach may serve as an effective vaccination strategy in future attempts to control TB.


Assuntos
Vacina BCG/imunologia , Epitopos de Linfócito T , Tuberculose/prevenção & controle , Vacinas de DNA/imunologia , Animais , Antígenos de Bactérias/imunologia , Vacina BCG/genética , Vacina BCG/farmacologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/genética , Feminino , Memória Imunológica , Interferon gama/metabolismo , Tuberculose Latente/prevenção & controle , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Vacinas de DNA/farmacologia
4.
Medicine (Baltimore) ; 99(36): e22015, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32899054

RESUMO

INTRODUCTION: Tuberculosis (TB) is a global infectious disease. In low-incidence countries, paediatric TB affects mostly immigrant children and children of immigrants. We hypothesize that these children are at risk of exposure to Mycobacterium tuberculosis when they travel to the country of origin of their parents to visit friends and relatives (VFR). In this study, we aim to estimate the incidence rate and risk factors associated to latent tuberculosis infection (LTBI) and TB in VFR children. METHODS AND ANALYSIS: A prospective study will be carried out in collaboration with 21 primary health care centres (PCC) and 5 hospitals in Catalonia, Spain. The study participants are children under 15 years of age, either immigrant themselves or born to immigrant parents, who travel to countries with high incidence of TB (≥ 40 cases/100,000 inhabitants). A sample size of 492 children was calculated. Participants will be recruited before traveling, either during a visit to a travel clinic or to their PCC, where a questionnaire including sociodemographic, epidemiological and clinical data will be completed, and a tuberculin skin test (TST) will be performed and read after 48 to 72 hours; patients with a positive TST at baseline will be excluded. A visit will be scheduled eight to twelve-weeks after their return to perform a TST and a QuantiFERON-TB Gold Plus test. The incidence rate of LTBI will be estimated per individual/month and person/year per country visited, and also by age-group. ETHICS AND DISSEMINATION: The study protocol was approved by the Clinical Research Ethics Committee of the Hospital Universitari Mútua Terrassa (code 02/16) and the Clinical Research Ethics Committee of the Fundació Institut Universitari per a la Recerca a l'Atenció Primària de Salut Jordi Gol i Gurina (code P16/094). Articles will be published in indexed scientific journals. TRIAL REGISTRATION: Clinical-Trials.gov: NCT04236765.


Assuntos
Tuberculose Latente/epidemiologia , Tuberculose Latente/transmissão , Mycobacterium tuberculosis/isolamento & purificação , Adolescente , Criança , Testes Diagnósticos de Rotina/métodos , Emigrantes e Imigrantes , Família , Feminino , Amigos , Humanos , Incidência , Testes de Liberação de Interferon-gama/métodos , Tuberculose Latente/diagnóstico , Masculino , Mycobacterium tuberculosis/imunologia , Estudos Prospectivos , Fatores de Risco , Espanha/epidemiologia , Viagem/tendências , Teste Tuberculínico/métodos
5.
Nat Commun ; 11(1): 4870, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978384

RESUMO

Little is known about the physiology of latent Mycobacterium tuberculosis infection. We studied the mutational rates of 24 index tuberculosis (TB) cases and their latently infected household contacts who developed active TB up to 5.25 years later, as an indication of bacterial physiological state and possible generation times during latent TB infection in humans. Here we report that the rate of new mutations in the M. tuberculosis genome decline dramatically after two years of latent infection (two-sided p < 0.001, assuming an 18 h generation time equal to log phase M. tuberculosis, with latency period modeled as a continuous variable). Alternatively, assuming a fixed mutation rate, the generation time increases over the latency duration. Mutations indicative of oxidative stress do not increase with increasing latency duration suggesting a lack of host or bacterial derived mutational stress. These results suggest that M. tuberculosis enters a quiescent state during latency, decreasing the risk for mutational drug resistance and increasing generation time, but potentially increasing bacterial tolerance to drugs that target actively growing bacteria.


Assuntos
Tuberculose Latente/microbiologia , Taxa de Mutação , Mycobacterium tuberculosis/genética , Tuberculose/microbiologia , Adulto , Brasil , DNA Bacteriano/isolamento & purificação , Feminino , Genoma Bacteriano , Humanos , Masculino , Mutação , Mycobacterium tuberculosis/patogenicidade , Estresse Oxidativo , Filogenia , Polimorfismo de Nucleotídeo Único , Fatores de Tempo , Adulto Jovem
7.
Public Health Rep ; 135(1_suppl): 172S-181S, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735191

RESUMO

OBJECTIVE: Targeted testing and treatment of persons with latent tuberculosis infection (LTBI) is a critical component of the US tuberculosis (TB) elimination strategy. In January 2016, the California Department of Public Health issued a tool and user guide for TB risk assessment (California tool) and guidance for LTBI testing, and in September 2016, the US Preventive Services Task Force (USPSTF) issued recommendations for LTBI testing in primary care settings. We estimated the epidemiologic effect of adherence to both recommendations in California. METHODS: We used an individual-based Markov micro-simulation model to estimate the number of cases of TB disease expected through 2026 with baseline LTBI strategies compared with implementation of the USPSTF or California tool guidance. We estimated the risk of LTBI by age and country of origin, the probability of being in a targeted population, and the probability of presenting for primary care based on available data. We assumed 100% adherence to testing guidance but imperfect adherence to treatment. RESULTS: Implementation of USPSTF and California tool guidance would result in nearly identical numbers of tests administered and cases of TB disease prevented. Perfect adherence to either recommendation would result in approximately 7000 cases of TB disease averted (40% reduction compared with baseline) by 2026. Almost all of this decline would be driven by a reduction in the number of cases among non-US-born persons. CONCLUSIONS: By focusing on the non-US-born population, adherence to LTBI testing strategies recommended by the USPSTF and the California tool could substantially reduce the burden of TB disease in California in the next decade.


Assuntos
Tuberculose Latente/diagnóstico , Atenção Primária à Saúde/organização & administração , Adulto , Fatores Etários , Antituberculosos/uso terapêutico , California , Emigrantes e Imigrantes , Fidelidade a Diretrizes , Humanos , Hospedeiro Imunocomprometido , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/etnologia , Cadeias de Markov , Programas de Rastreamento , Guias de Prática Clínica como Assunto , Atenção Primária à Saúde/normas , Instituições Residenciais , Medição de Risco , Tuberculose/etnologia
8.
Med Lav ; 111(3): 170-183, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32624559

RESUMO

INTRODUCTION: Despite great efforts, tuberculosis (TB) is still a major public health threat worldwide. For decades, TB control programs have focused almost exclusively on infectious TB active cases.  However, it is evident that this strategy alone cannot achieve TB elimination. To achieve this objective a comprehensive strategy directed toward integrated latent tuberculosis infection (LTBI) management is needed. Recently it has been recognized that LTBI is not a stable condition but rather a spectrum of infections (e.g., intermittent, transient or progressive) which may lead to incipient, then subclinical, and finally active TB disease. AIM: Provide an overview of current available LTBI diagnostic test including updates, future developments and perspectives. RESULTS: There is currently no test for the direct identification of live MT infection in humans. The diagnosis of LTBI is indirect and relies on the detection of an immune response against MT antigens, assuming that the immune response has developed after a contact with the biological agent. Tuberculin skin test (TST) and interferon gamma release assays (IGRAs) are the main diagnostic tools for LTBI, however, both present strengths and limitations. The most ancient diagnostic test (TST) can be associated with several technical errors, has limited positive predictive value, is being influenced by BCG vaccination and several conditions can reduce the skin reactivity. Notwithstanding these limitations, prompt identification of TST conversion, should orientate indications for preventive therapy of LTBI. IGRAs have superior specificity, are not affected by M. bovis, BCG vaccination and other environmental mycobacteria. However, they present some logistical and organisational constraints and are more expensive. Currently, the WHO guidelines recommend that either a TST or an IGRA can be used to detect LTBI in high-income and upper middle-income countries with estimated TB incidences less than 100 per 100,000 population. Two skin tests (C-TB and Diaskintest), using only two specific M. tuberculosis antigens (ESAT-6 and CFP-10) instead of the tuberculin solution, have recently been developed but, to date, none of these tests is available on the European market. CONCLUSION: Early identification and treatment of individuals with LTBI is an important priority for TB control in specific groups at risk within the population: this is of crucial meaning in recently infected cases both at the community level and in some occupational settings. Currently there is no gold standard test for LTBI: an improved understanding of the available tests is needed to develop better tools for diagnosing LTBI and predicting progression to clinical active disease.


Assuntos
Tuberculose Latente , Tuberculose , Humanos , Interferon gama , Tuberculose Latente/diagnóstico , Sensibilidade e Especificidade , Teste Tuberculínico
9.
PLoS Pathog ; 16(7): e1008413, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32730321

RESUMO

Human immunodeficiency virus infection is the most common risk factor for severe forms of tuberculosis (TB), regardless of CD4 T cell count. Using a well-characterized cynomolgus macaque model of human TB, we compared radiographic, immunologic and microbiologic characteristics of early (subclinical) reactivation of latent M. tuberculosis (Mtb) infection among animals subsequently infected with simian immunodeficiency virus (SIV) or who underwent anti-CD4 depletion by a depletion antibody. CD4 depleted animals had significantly fewer CD4 T cells within granulomas compared to Mtb/SIV co-infected and Mtb-only control animals. After 2 months of treatment, subclinical reactivation occurred at similar rates among CD4 depleted (5 of 7 animals) and SIV infected animals (4 of 8 animals). However, SIV-induced reactivation was associated with more dissemination of lung granulomas that were permissive to Mtb growth resulting in greater bacterial burden within granulomas compared to CD4 depleted reactivators. Granulomas from Mtb/SIV animals displayed a more robust T cell activation profile (IFN-α, IFN-γ, TNF, IL-17, IL-2, IL-10, IL-4 and granzyme B) compared to CD4 depleted animals and controls though these effectors did not protect against reactivation or dissemination, but instead may be related to increased viral and/or Mtb antigens. SIV replication within the granuloma was associated with reactivation, greater overall Mtb growth and reduced Mtb killing resulting in greater overall Mtb burden. These data support that SIV disrupts protective immune responses against latent Mtb infection beyond the loss of CD4 T cells, and that synergy between SIV and Mtb occurs within granulomas.


Assuntos
Coinfecção/imunologia , Tuberculose Latente/imunologia , Tuberculose Latente/virologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Ativação Viral/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Granuloma/virologia , Hospedeiro Imunocomprometido/imunologia , Macaca fascicularis , Mycobacterium tuberculosis/imunologia , Vírus da Imunodeficiência Símia/imunologia
10.
BMC Infect Dis ; 20(1): 469, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32615981

RESUMO

BACKGROUND: Interferon-γ release assays (IGRA) with Resuscitation promoting factor (Rpf) proteins enhanced tuberculosis (TB) screening and diagnosis in adults but have not been evaluated in children. Children often develop paucibacillary TB and their immune response differs from that of adults, which together affect TB disease diagnostics and immunodiagnostics. We assessed the ability of Rpf to identify infection among household TB-exposed children in The Gambia and investigated their ability to discriminate Mycobacterium tuberculosis complex (MTBC) infection from active TB disease in children. METHODS: Detailed clinical investigations were done on 93 household TB-exposed Gambian children and a tuberculin skin test (TST) was administered to asymptomatic children. Venous blood was collected for overnight stimulation with ESAT-6/CFP-10-fusion protein (EC), purified protein derivative and RpfA, B, C, D and E. Interferon gamma (IFN-γ) production was measured by ELISA in supernatants and corrected for the background level. Infection status was defined by IGRA with EC and TB disease by mycobacterial confirmation and/or clinical diagnosis. We compared IFN-γ levels between infected and uninfected children and between infected and TB diseased children using a binomial logistic regression model while correcting for age and sex. A Receiver Operating Characteristics analysis was done to find the best cut-off for IFN-γ level and calculate sensitivity and specificity. RESULTS: Interferon gamma production was significantly higher in infected (IGRA+, n = 45) than in uninfected (IGRA-, n = 20) children after stimulation with RpfA, B, C, and D (P = 0.03; 0.007; 0.03 and 0.003, respectively). Using RpfB and D-specific IFN-γ cut-offs (33.9 pg/mL and 67.0 pg/mL), infection was classified with a sensitivity-specificity combination of 73-92% and 77-72% respectively, which was similar to and better than 65-75% for TST. Moreover, IFN-γ production was higher in infected than in TB diseased children (n = 28, 5 bacteriologically confirmed, 23 clinically diagnosed), following RpfB and D stimulation (P = 0.02 and 0.03, respectively). CONCLUSION: RpfB and RpfD show promising results for childhood MTBC infection screening, and both performed similar to and better than the TST in our study population. Additionally, both antigens appear to discriminate between infection and disease in children and thus warrant further investigation as screening and diagnostic antigens for childhood TB.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Citocinas/imunologia , Testes de Liberação de Interferon-gama/métodos , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Programas de Rastreamento/métodos , Mycobacterium tuberculosis/imunologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Características da Família , Feminino , Gâmbia/epidemiologia , Humanos , Interferon gama/imunologia , Interferon gama/metabolismo , Tuberculose Latente/microbiologia , Masculino , Sensibilidade e Especificidade , Teste Tuberculínico
13.
Ann Hematol ; 99(9): 2201-2203, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32699943
14.
BMC Infect Dis ; 20(1): 294, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32664847

RESUMO

BACKGROUND: Tuberculosis (TB) is the most common opportunistic infection and the leading cause of death in people living with HIV (PLHIV). HIV-infected children are at a higher risk of TB infection and disease compared to those without HIV. Isoniazid preventive therapy (IPT) is an effective intervention in preventing progression of latent TB infection to active TB. The World Health Organization (WHO) currently recommends that all children aged > 12 months and adults living with HIV in whom active TB has been excluded should receive a 6-months course of IPT as part of a comprehensive package of HIV care. Despite this recommendation, the uptake of IPT among PLHIV has been suboptimal globally. This study sought to determine the factors affecting IPT uptake and completion among HIV-infected children in a large HIV care centre in Nairobi, Kenya. METHOD: This was a cross-sectional mixed methods study comprising of quantitative and qualitative study designs. Medical records of 225 HIV-infected children aged 1 to < 10 years, in care in the Kenyatta National Hospital Comprehensive Care Centre (KNH CCC) were retrospectively reviewed, and 8 purposively selected healthcare providers and 18 consecutively selected caregivers of children were interviewed. RESULTS: IPT uptake among CLHIV in care in the KNH CCC was 68% (152/225) while the treatment completion rate was 82% (94/115). IPT-related health education and counselling were the main facilitators of IPT uptake and completion, while fear of adverse drug reaction, pill burden and lack of an integrated monitoring and evaluation system for IPT were the major barriers. CONCLUSION: The IPT uptake in this study was low and fell short of the set global target of > 90%. The completion rate was however acceptable. There is an urgent need to address the identified barriers.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Antituberculosos/uso terapêutico , Isoniazida/uso terapêutico , Tuberculose Latente/tratamento farmacológico , Tuberculose Latente/prevenção & controle , Adulto , Antituberculosos/efeitos adversos , Criança , Pré-Escolar , Aconselhamento , Estudos Transversais , Feminino , Pessoal de Saúde , Humanos , Lactente , Isoniazida/efeitos adversos , Quênia , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Pesquisa Qualitativa , Encaminhamento e Consulta , Estudos Retrospectivos , Resultado do Tratamento , Recusa do Paciente ao Tratamento
15.
S Afr Med J ; 110(4): 313-319, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32657744

RESUMO

BACKGROUND: The goal of antiretroviral therapy (ART) is to suppress viral replication to undetectable levels. These low viral load (VL) levels may not be attained in some patients, a situation representing potential virological failure during the course of treatment. OBJECTIVES: To present the results of a Markov model exploring how virological failure and active tuberculosis (TB) affect the progression of HIV in patients on ART. METHODS: A continuous-time non-homogeneous Markov model was used to model the progression of HIV/AIDS in patients on combination ART (cART). We define seven states in our model. The first five states are based on VL levels and the other two are absorbing states: death and withdrawal from the study. The effects of TB co-infection, baseline VL, lactic acidosis and treatment failure on transition intensities were assessed. RESULTS: The model shows that VL-based transition intensities do not follow a constant rate; rather, there are two different trends in HIV/AIDS progression. The first trend is an increase in the prevalence of state 1 (undetectable VL levels) in the first 0.5 years of treatment. The second trend follows thereafter and shows a slow decrease. Within the first 0.5 years of therapeutic intervention, the undetectable VL state is therefore attainable from any VL state. However, when virological failure occurs, there is an increased risk of death. Developing active TB while on cART increases the risk of viral rebound from undetectable levels to VLs between 50 and 10 000 copies/mL by ~1.03-fold. From a VL between 10 000 and 100 000 copies/mL, developing TB while on cART increases the rate of viral rebound by ~2.5-fold. However, if TB is detected and treated at enrolment, rates of viral rebound from undetectable levels are reduced. CONCLUSIONS: The model confirms that virological failure, coupled with developing active TB while on cART, increases mortality rates irrespective of patient CD4+ count status. It also suggests that while TB at the time of cART initiation does not increase the risk of viral rebound, development of active TB after cART initiation does increase this risk. These findings highlight the importance of strengthening VL monitoring, which should be performed every 2 months, especially in patients with TB, and addressing unsuppressed VLs appropriately if they are detected.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Antituberculosos/uso terapêutico , Coinfecção , Infecções por HIV/tratamento farmacológico , Tuberculose/tratamento farmacológico , Acidose Láctica/induzido quimicamente , Síndrome de Imunodeficiência Adquirida/sangue , Síndrome de Imunodeficiência Adquirida/complicações , Síndrome de Imunodeficiência Adquirida/tratamento farmacológico , Adolescente , Adulto , Idoso , Contagem de Linfócito CD4 , Progressão da Doença , Interações Medicamentosas , Farmacorresistência Viral , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Humanos , Tuberculose Latente/complicações , Masculino , Cadeias de Markov , Adesão à Medicação , Pessoa de Meia-Idade , Mortalidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , População Rural , África do Sul , Resposta Viral Sustentada , Falha de Tratamento , Tuberculose/complicações , Carga Viral , Adulto Jovem
16.
PLoS One ; 15(7): e0235261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614873

RESUMO

BACKGROUND: Tuberculosis (TB) is the leading cause of death among people living with HIV (PLWH), and current evidence suggests that heavy alcohol users have an increased risk of developing TB disease compared to non-drinkers. Not known is whether the increased risk for TB disease among alcohol users may reflect higher rates of latent TB infection (LTBI) among this population. We assessed the latent TB infection prevalence based on tuberculin skin testing (TST) and examined association with current alcohol use among HIV-infected persons on antiretroviral therapy (ART) in south-western Uganda. METHODS: We included PLWH at the Mbarara Regional Hospital HIV clinic, who were either current alcohol consumers (prior 3 months) or past year abstainers (2:1 enrolment ratio). Participants were recruited for a study of isoniazid preventive therapy for LTBI. TST was performed using 5 tuberculin units of purified protein derivative. The primary outcome was a positive TST reading (≥5mm induration), reflecting LTBI. We used logistic regression analyses to assess the cross-sectional association between self-reported current alcohol use and a positive TST. RESULTS: Of the 295 of 312 (95%) who returned for TST reading, 63% were females and 63% were current alcohol drinkers. The TST positive prevalence was 27.5% (95% confidence interval [CI]: 22.6% - 32.9%). The odds of a positive TST for current alcohol users compared to abstainers was 0.76 (95% CI: 0.41, 1.41), controlling for gender, age, body mass index, history of smoking, and prior unhealthy alcohol use. CONCLUSIONS: The prevalence of LTBI among PLWH on ART in south-western Uganda was moderate and LTBI poses a risk for future infectious TB. Although alcohol use is common, we did not detect an association between current drinking or prior unhealthy alcohol use and LTBI. Further studies to evaluate the association between LTBI and different levels of current drinking (heavy versus not) are needed.


Assuntos
Consumo de Bebidas Alcoólicas , Infecções por HIV/complicações , Tuberculose Latente/etiologia , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Tuberculose Latente/diagnóstico , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Teste Tuberculínico , Uganda/epidemiologia
17.
PLoS One ; 15(6): e0235254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32603343

RESUMO

OBJECTIVE: An interferon-gamma release assay (IGRA) is used to screen for latent tuberculosis infection (LTBI). Among IGRAs, the QuantiFERON-TB Gold In-Tube (QFT-GIT) results are highly variable, so the borderline zone has been proposed to reduce unnecessary LTBI treatment. The aim of this study was to examine the proportion of the borderline zone of QFT-GIT in healthcare workers' (HCWs) serial IGRA and to retrospectively identify the utility of predicting tuberculosis (TB) in a moderate TB incidence setting. METHODS: The participants were HCWs who had undergone serial LTBI screening between June 2013 and June 2018. IGRA-positive HCWs underwent examinations that included low-dose computed tomography (LDCT) and TB culture, if necessary. Applying the borderline zone (0.2-<0.7 IU/mL), the results were classified as definite negative, borderline negative, borderline positive and definite positive. RESULTS: Through the follow-up of 477 HCWs, 441 (92.5%) invariant, 30 (6.3%) conversion, 2 (0.4%) reversion and 5 (1.0%) indeterminate results were observed with the manufacturer's cutoff. Applying the borderline zone, 419 (87.8%) invariant, 22 (4.6%) conversion, 1 (0.2%) reversion and 36 (7.5%) decision pending, including 5 (1.0%) indeterminate results, were observed. At the time of screening, five TB cases were identified. Chest X-ray (CXR) identified one TB case, and LDCT identified four additional TB cases. After one year, two TB cases were diagnosed, and their screening QFT-GIT results were definite positive and borderline negative. In the Cochran-Armitage trend test, the greater the maximum difference in the QFT-GIT grade with the borderline zone was, the higher the probability of developing TB (P-value <0.001). CONCLUSION: The application of the borderline zone lowered the conversion rate but increased the decision pending rate. Introducing the borderline zone requires a careful approach, and a thorough examination needs to be performed to rule out TB in converters. HCWs with borderline QFT-GIT results also need close observation.


Assuntos
Testes de Liberação de Interferon-gama , Tuberculose Latente/diagnóstico , Adulto , Feminino , Pessoal de Saúde , Humanos , Incidência , Testes de Liberação de Interferon-gama/métodos , Testes de Liberação de Interferon-gama/estatística & dados numéricos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Tuberculose/diagnóstico , Adulto Jovem
18.
PLoS One ; 15(7): e0235859, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687494

RESUMO

In our work, we aim to identify new candidate host biomarkers to discriminate between active TB patients (n = 28), latent infection (LTBI; n = 27) and uninfected (NoTBI; n = 42) individuals. For that, active TB patients and their contacts were recruited that donated serum and saliva samples. A multiplex assay was performed to study the concentration of different cytokines, chemokines and growth factors. Proteins with significant differences between groups were selected and logistic regression and the area under the ROC curve (AUC) was used to assess the diagnostic accuracy. The best marker combinations that discriminate active TB from NoTBI contacts were [IP-10 + IL-7] in serum and [Fractalkine + IP-10 + IL-1α + VEGF] in saliva. Best discrimination between active TB and LTBI was achieved using [IP-10 + BCA-1] in serum (AUC = 0.83) and IP-10 in saliva (p = 0.0007; AUC = 0.78). The levels of TNFα (p = 0.003; AUC = 0.73) in serum and the combination of [Fractalkine+IL-12p40] (AUC = 0.83) in saliva, were able to differentiate between NoTBI and LTBI contacts. In conclusion, different individual and combined protein markers could help to discriminate between active TB and both uninfected and latently-infected contacts. The most promising ones include [IP-10 + IL-7], [IP-10 + BCA-1] and TNFα in serum and [Fractalkine + IP-10 + IL-1α + VEGF], IP-10 and [Fractalkine+IL-12p40] in saliva.


Assuntos
Quimiocina CX3CL1/sangue , Quimiocina CXCL10/sangue , Interleucinas/sangue , Tuberculose Latente/sangue , Tuberculose Pulmonar/sangue , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto , Idoso , Biomarcadores/sangue , Biomarcadores/metabolismo , Quimiocina CX3CL1/análise , Quimiocina CXCL10/análise , Feminino , Humanos , Interleucinas/análise , Tuberculose Latente/diagnóstico , Tuberculose Latente/metabolismo , Masculino , Pessoa de Meia-Idade , Saliva/química , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise
19.
N Engl J Med ; 383(4): 359-368, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32706534

RESUMO

BACKGROUND: Vitamin D metabolites support innate immune responses to Mycobacterium tuberculosis. Data from phase 3, randomized, controlled trials of vitamin D supplementation to prevent tuberculosis infection are lacking. METHODS: We randomly assigned children who had negative results for M. tuberculosis infection according to the QuantiFERON-TB Gold In-Tube assay (QFT) to receive a weekly oral dose of either 14,000 IU of vitamin D3 or placebo for 3 years. The primary outcome was a positive QFT result at the 3-year follow-up, expressed as a proportion of children. Secondary outcomes included the serum 25-hydroxyvitamin D (25[OH]D) level at the end of the trial and the incidence of tuberculosis disease, acute respiratory infection, and adverse events. RESULTS: A total of 8851 children underwent randomization: 4418 were assigned to the vitamin D group, and 4433 to the placebo group; 95.6% of children had a baseline serum 25(OH)D level of less than 20 ng per milliliter. Among children with a valid QFT result at the end of the trial, the percentage with a positive result was 3.6% (147 of 4074 children) in the vitamin D group and 3.3% (134 of 4043) in the placebo group (adjusted risk ratio, 1.10; 95% confidence interval [CI], 0.87 to 1.38; P = 0.42). The mean 25(OH)D level at the end of the trial was 31.0 ng per milliliter in the vitamin D group and 10.7 ng per milliliter in the placebo group (mean between-group difference, 20.3 ng per milliliter; 95% CI, 19.9 to 20.6). Tuberculosis disease was diagnosed in 21 children in the vitamin D group and in 25 children in the placebo group (adjusted risk ratio, 0.87; 95% CI, 0.49 to 1.55). A total of 29 children in the vitamin D group and 34 in the placebo group were hospitalized for treatment of acute respiratory infection (adjusted risk ratio, 0.86; 95% CI, 0.52 to 1.40). The incidence of adverse events did not differ significantly between the two groups. CONCLUSIONS: Vitamin D supplementation did not result in a lower risk of tuberculosis infection, tuberculosis disease, or acute respiratory infection than placebo among vitamin D-deficient schoolchildren in Mongolia. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT02276755.).


Assuntos
Colecalciferol/uso terapêutico , Suplementos Nutricionais , Tuberculose Latente/prevenção & controle , Mycobacterium tuberculosis , Vitaminas/uso terapêutico , Criança , Colecalciferol/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Incidência , Tuberculose Latente/epidemiologia , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , Falha de Tratamento , Teste Tuberculínico , Vitamina D/análogos & derivados , Vitamina D/sangue , Vitaminas/efeitos adversos
20.
PLoS One ; 15(6): e0233385, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32502176

RESUMO

BACKGROUND: Diabetes triples the risk of developing tuberculosis (TB). This study was designed to determine the prevalence of past and current TB disease and Latent TB infection (LTBI) in type 2 Diabetes Mellitus (NIDDM) patients. DESIGN: This was a prospective descriptive study on all NIDDM patients attending a Diabetic clinic. Detailed history, included details of previous history of TB (Past TB)and symptoms of active TB and a thorough physical exam was also done. When clinical suspicion of TB was present, appropriate investigations were carried out to diagnose 'Current TB'. Subsequently, 200 consecutive patients who were negative for Past and Current TB were screened for Latent TB infection (LTBI) by tuberculin skin test. RESULTS: Of 1000 NIDDM patients enrolled, 43(4.3%) had Past TB. Of remaining 957 patients, 50 were evaluated for New TB on the basis of suggestive symptoms and 10(1%) patients were confirmed to have Current TB. Risk factors for Past or Current TB 'DM-TB' in comparison with 'DM Only' group were; male sex (72% VS 57%; P = 0.033), manual laborer (28% VS 15%; P = 0.012), smoking (26% VS 14%; P = 0.015), alcohol consumption (23% VS 9%; P<0.001)& being on treatment with Insulin (40% VS 20%; P<0.001). There was a protective effect with being a home maker (17% VS 37%; P = 0.034&overweightstatus (53% VS 71%; P = 0.004). Of the 200 patient without Past or Current TB, who were screened for LTBI, 96(48%) patients were found to have LTBI. Male sex was the only significant risk factor for LTBI (72% VS 59%; P = 0.05). CONCLUSION: Past and Current TB was substantial in patients attending a Diabetic Clinic. Active symptom screening for TB in these clinics could lead to increase in case detection and earlier diagnosis.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Tuberculose Latente/diagnóstico , Tuberculose/diagnóstico , Adulto , Idoso , Diabetes Mellitus Tipo 2/microbiologia , Feminino , Humanos , Índia/epidemiologia , Tuberculose Latente/epidemiologia , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Centros de Atenção Terciária , Teste Tuberculínico , Tuberculose/epidemiologia
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