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1.
J Infect Dis ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820119

RESUMO

Diagnosis of M. tuberculosis (Mtb) infection in close contacts is critical for TB control. Smoking is a risk factor for Mtb infection and TB disease but its effect on longitudinal interferon-gamma release assay (IGRA) results remains unknown. We conducted a multi-site prospective study in Brazil between 2015-2019, among close contacts of adults with culture-confirmed pulmonary TB. IGRA was performed at baseline, month 6 if negative at baseline, and month 24-30 after enrollment. IGRA results were categorized as IGRA-positive (maintained from baseline to last visit), IGRA-conversion (from negative to positive at any time), IGRA-reversion (from positive to negative at any time), and IGRA-negative (maintained from baseline to last visit). Associations between IGRA results and smoking status at baseline (current/former vs never) in contacts were evaluated using propensity score-adjusted logistic regression models. Estimated propensity score was used as a covariate in models, which regressed the outcome (IGRA-positive, IGRA-conversion, IGRA-reversion) on smoking status. Of 430 close contacts, 89 (21%) were IGRA-positive, 30 (7%) were converters, 30 (7%) were reverters and 22 were indeterminate. Smoking frequency was 26 (29%) among IGRA-positive contacts, 7 (23%) in converters, and 3 (10%) in reverters. Smoking in contacts was associated with lower odds of IGRA-reversion (adjusted odds ratio = 0.16; 95% confidence interval = [0.03-0.70]). We did not detect associations between smoking and IGRA-positive or IGRA-conversion. Our findings highlight the importance of smoking on longitudinal IGRA results. This has implications for clinical care and clinical trials in which IGRA status is monitored or used as an outcome.

2.
Clin Infect Dis ; 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38170196

RESUMO

BACKGROUND: The Xpert® MTB/RIF rapid molecular test provides a quantitative measure of Mycobacterium tuberculosis (Mtb) DNA in the form of cycle threshold (Ct) values. This information can be translated into mycobacterial load and used as a potential risk measure of bacterial spread for tuberculosis cases, which can impact infection control. However, the role of Ct values in assessing Mtb transmission to close contacts has not yet been demonstrated. METHODS: A prospective study was performed to investigate the association between Xpert® MTB/RIF Ct values and Mtb transmission to close contacts of patients with culture-confirmed pulmonary TB in a multi-center Brazilian cohort. We evaluated clinical and laboratory data, such as age, sex, race, smoking habits, drug use, alcohol use, chest radiograph, Xpert® MTB/RIF results among pulmonary tuberculosis cases, and QuantiFERON(QFT)-Plus results at baseline and after six months for close contacts who had a negative result at baseline. RESULTS: A total of 1,055 close contacts of 382 pulmonary tuberculosis cases were included in the study. The median Ct values from pulmonary tuberculosis cases of QFT-Plus positive (at baseline or six months) close contacts were lower compared with those who were QFT-Plus negative. An adjusted logistic regression demonstrated that reduced Ct values from the index cases were independently associated with QFT-Plus conversion from negative to positive (OR: 1.61, 95% CI: 1.12-2.32) after adjusting for clinical characteristics. CONCLUSION: Close contacts of pulmonary TB index cases exhibiting low Xpert MTB/RIF Ct values displayed higher rates of TB infection, reflecting Mtb transmission.

3.
Front Med (Lausanne) ; 9: 972145, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186793

RESUMO

Background: Tuberculosis (TB) is a worldwide public health problem, especially in countries that also report high numbers of people living with HIV (PLWH) and/or diabetes mellitus (DM). However, the unique features of persons with TB-HIV-DM are incompletely understood. This study compared anti-TB treatment (ATT) outcomes of diabetic and non-diabetic TB/HIV co-infected patients. Methods: A nationwide retrospective observational investigation was performed with data from the Brazilian Tuberculosis Database System among patients reported to have TB-HIV co-infection between 2014 and 2019. This database includes all reported TB cases in Brazil. Exploratory and association analyses compared TB treatment outcomes in DM and non-DM patients. Unfavorable outcomes were defined as death, treatment failure, loss to follow-up or recurrence. Multivariable stepwise logistic regressions were used to identify the variables associated with unfavorable ATT outcomes in the TB-HIV population. Results: Of the 31,070 TB-HIV patients analyzed, 999 (3.2%) reported having DM. However, in these TB-HIV patients, DM was not associated with any unfavorable treatment outcome [adjusted Odds Ratio (aOR): 0.97, 95% CI: 0.83-1.12, p = 0.781]. Furthermore, DM was also not associated with any specific type of unfavorable outcome in this study. In both the TB-HIV group and the TB-HIV-DM subpopulation, use of alcohol, illicit drugs and tobacco, as well as non-white ethnicity and prior TB were all characteristics more frequently observed in persons who experienced an unfavorable ATT outcome. Conclusion: DM is not associated with unfavorable TB treatment outcomes in persons with TB-HIV, including death, treatment failure, recurrence and loss to follow up. However, consumption habits, non-white ethnicity and prior TB are all more frequently detected in those with unfavorable outcomes in both TB-HIV and TB-HIV-DM patients.

4.
Int J Infect Dis ; 116: 293-301, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35033658

RESUMO

BACKGROUND: Dysglycemia (i.e., prediabetes or diabetes) in patients with tuberculosis (PWTB) is associated with increased odds of mortality and treatment failure. Whether such association holds true when dysglycemia is transient or persistent is unknown. In this study, we tested the association between persistent dysglycemia (PD) during anti-tuberculosis (TB) treatment and unfavorable treatment outcomes in PWTB from Lima, Peru. METHODS: PWTB enrolled between February and November 2017 were followed for 24-months. Dysglycemia was measured through fasting glucose and HbA1c at baseline during the 2nd- and 6th-month of TB treatment. PD was defined as dysglycemia detected in 2 different visits. The association between PD and unfavorable TB treatment outcome was evaluated using logistic regression. RESULTS: Among 125 PWTB, PD prevalence was 29.6%. PD was associated with more lung lesion types, higher bacillary loads, low hemoglobin (Hb), and high body mass index (BMI). Unfavorable TB treatment outcome was associated with older age, higher BMI, more lung lesion types, and PD. After adjusting for age, Hb levels, smoking, and smear grade, PD was independently associated with unfavorable treatment outcomes (adjusted odds ratio (aOR): 6.1; 95% CI: 1.9-19.6). CONCLUSION: PD is significantly associated with higher odds of unfavorable TB treatment outcomes. Dysglycemia control during anti-TB treatment gives the opportunity to introduce appropriate interventions to TB management.


Assuntos
Estado Pré-Diabético , Tuberculose Pulmonar , Tuberculose , Humanos , Peru/epidemiologia , Estado Pré-Diabético/complicações , Estado Pré-Diabético/epidemiologia , Resultado do Tratamento , Tuberculose/complicações , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/epidemiologia
5.
J Infect Dis ; 225(4): 617-626, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34651642

RESUMO

BACKGROUND: It is unclear whether diabetes or prediabetes affects unfavorable treatment outcomes and death in people with tuberculosis (PWTB). METHODS: Culture-confirmed, drug-susceptible PWTB, enrolled in the Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil cohort between 2015 and 2019 (N = 643) were stratified based on glycemic status according to baseline glycated hemoglobin. Unfavorable tuberculosis (TB) outcome was defined as treatment failure or modification, recurrence, or death; favorable outcome was cure or treatment completion. We corroborated the findings using data from PWTB reported to the Brazilian National System of Diseases Notification (SINAN) during 2015-2019 (N = 20 989). Logistic regression models evaluated associations between glycemic status and outcomes. RESULTS: In both cohorts, in univariate analysis, unfavorable outcomes were more frequently associated with smoking, illicit drug use, and human immunodeficiency virus infection. Diabetes, but not prediabetes, was associated with unfavorable outcomes in the RePORT-Brazil (adjusted relative risk [aRR], 2.45; P < .001) and SINAN (aRR, 1.76; P < .001) cohorts. Furthermore, diabetes was associated with high risk of death (during TB treatment) in both RePORT-Brazil (aRR, 2.16; P = .040) and SINAN (aRR, 1.93; P = .001). CONCLUSIONS: Diabetes was associated with an increased risk of unfavorable outcomes and mortality in Brazilian PWTB. Interventions to improve TB treatment outcomes in persons with diabetes are needed.


Assuntos
Diabetes Mellitus , Estado Pré-Diabético , Tuberculose , Antituberculosos/uso terapêutico , Estudos de Coortes , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Humanos , Estado Pré-Diabético/complicações , Estado Pré-Diabético/tratamento farmacológico , Estudos Prospectivos , Resultado do Tratamento , Tuberculose/complicações , Tuberculose/tratamento farmacológico
6.
Microbiol Spectr ; 9(3): e0116321, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34851140

RESUMO

The interferon gamma release assay (IGRA) has emerged as a useful tool for identifying latent tuberculosis infection (LTBI). This assay can be performed through testing platforms such as the QuantiFERON-TB Gold Plus (QFT-Plus) assay. This in vitro test has been incorporated into several guidelines worldwide and has recently been considered by the World Health Organization (WHO) for the diagnosis of LTBI. The possibility of systematically implementing IGRAs such as the QFT-Plus assay in centers that perform LTBI screening has been accelerated by the decreased availability of the tuberculin skin test (TST) in several countries. Nevertheless, the process to implement IGRA testing in routine clinical care has many gaps. The study utilized the expertise acquired by the laboratory teams of the Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil consortium during study protocol implementation of LTBI screening of tuberculosis (TB) close contacts. RePORT-Brazil includes clinical research sites from Brazilian cities and is the largest multicenter cohort of TB close contacts in the country to date. Operational and logistical challenges faced during IGRA implementation in all study laboratories are described, as well as the solutions that were developed and led to the successful establishment of IGRA testing in RePORT-Brazil. The descriptions of the problems identified and resolved in this study can assist laboratories implementing IGRAs, in addition to manufacturers of IGRAs providing effective technical support. This will facilitate the implementation of IGRA testing in countries with large TB burdens, such as Brazil. IMPORTANCE The IGRA has emerged as a useful tool for identifying persons with LTBI. Although the implementation of IGRAs is of utmost importance, to our knowledge there is scarce information on the identification of logistical and technical challenges for systematic screening for LTBI on a large scale. Thus, the descriptions of the problems identified and resolved in this study can assist laboratories implementing IGRAs, in addition to manufacturers of IGRAs providing effective technical support. This will facilitate the implementation of IGRA testing in countries with large TB burdens, such as Brazil.


Assuntos
Testes de Liberação de Interferon-gama/métodos , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Programas de Rastreamento/métodos , Mycobacterium tuberculosis/isolamento & purificação , Brasil/epidemiologia , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Tuberculose Latente/tratamento farmacológico , Estudos Prospectivos , Controle de Qualidade , Reprodutibilidade dos Testes , Manejo de Espécimes/métodos , Tuberculose/tratamento farmacológico , Tuberculose/prevenção & controle
7.
Front Med (Lausanne) ; 8: 706689, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34386510

RESUMO

Approximately 1.4 million people die annually worldwide from tuberculosis. Large epidemiologic studies can identify determinants of unfavorable clinical outcomes according to age, which can guide public health policy implementation and clinical management to improve outcomes. We obtained data from the national tuberculosis case registry; data were reported to the Brazilian National Program (SINAN) between 2010 and 2019. Clinical and epidemiologic variables were compared between age groups (child: <10 years, young: 10-24years, adult: 25-64years, and elderly: ≥65years). Univariate comparisons were performed together with second-generation p-values. We applied a backward stepwise multivariable logistic regression model to identify characteristics in each age group associated with unfavorable TB treatment outcomes. There were 896,314 tuberculosis cases reported during the period. Tuberculosis incidence was highest among adult males, but the young males presented the highest growth rate during the period. Directly observed therapy (DOT) was associated with protection against unfavorable outcomes in all age groups. The use of alcohol, illicit drugs, and smoking, as well as occurrence of comorbidities, were significantly different between age groups. Lack of DOT, previous tuberculosis, race, location of tuberculosis disease, and HIV infection were independent risk factors for unfavorable outcome depending on the age group. The clinical and epidemiological risk factors for unfavorable tuberculosis treatment outcomes varied according to age in Brazil. DOT was associated with improved outcomes in all age groups. Incidence according to age and sex identified adults and young males as the groups that need prevention efforts. This supports implementation of DOT in all populations to improve tuberculosis outcomes.

8.
Int J Infect Dis ; 103: 110-118, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33197582

RESUMO

BACKGROUND: A major goal of tuberculosis (TB) epidemiological studies is to obtain results that can be generalized to the larger population with TB. The ability to extrapolate findings on the determinants of TB treatment outcomes is also important. METHODS: We compared baseline clinical and demographic characteristics and determinants of anti-TB treatment outcomes between persons enrolled in the Regional Prospective Observational Research in Tuberculosis (RePORT)-Brazil cohort between June 2015 and June 2019, and the registry of TB cases reported to the Brazilian National TB Program (Information System for Notifiable Diseases [SINAN]) during the same time period. Multivariable regression models adjusted for the study site were performed using second-generation p-values, a novel statistical approach. Associations with unfavorable treatment outcomes were tested for both RePORT-Brazil and SINAN cohorts. FINDINGS: A total of 1,060 culture-confirmed TB patients were enrolled in RePORT-Brazil and 455,873 TB cases were reported to SINAN. Second-generation p-value analyses revealed that the cohorts were strikingly similar with regard to sex, age, use of antiretroviral therapy and positive initial smear sputum microscopy. However, diabetes, HIV infection, and smoking were more frequently documented in RePORT-Brazil. Illicit drug use, the presence of diabetes, and history of prior TB were associated with unfavorable TB treatment outcomes; illicit drug use was associated with such outcomes in both cohorts. CONCLUSIONS: There were important similarities in demographic characteristics and determinants of clinical outcomes between the RePORT-Brazil cohort and the Brazilian National registry of TB cases.


Assuntos
Tuberculose/terapia , Adulto , Brasil/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Tuberculose/complicações , Tuberculose/epidemiologia
9.
Am J Trop Med Hyg ; 103(6): 2492-2500, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32959763

RESUMO

Since 2018, adolescents have been included as a target group for tuberculosis (TB) surveillance by the WHO. However, they are considered a neglected population, as there are considerable gaps in information about them. We aimed to analyze the risk factors for unfavorable TB treatment outcomes among adolescents in Rio de Janeiro, a Brazilian city with a high burden of TB. This is a retrospective study of adolescents (10-18 years) with TB notified in Rio de Janeiro, from four national database systems, covering 2014-2016. "Extreme vulnerability" was defined as adolescents who presented one of the following characteristics: homelessness, incarceration, tobacco use, illicit drug use, or alcohol abuse. Logistic regression analysis was used to identify factors associated with favorable (cure/completed treatment) and unfavorable outcomes (lost to follow-up, death, and treatment failure). A total of 725 adolescents with TB were included: 610 (84.1%) were cured, 94 (13%) were lost to follow-up, six (0.8%) died because of TB, 13 (1.8%) died because of other causes, and two (0.3%) failed treatment. Unfavorable outcomes were associated with retreatment (adjusted odds ratio [aOR]: 4.51; 95% CI: 2.23-9.17), TB-HIV coinfection (aOR: 10.15; 95% CI: 4.15-25.34), extreme vulnerability (aOR: 3.01; 95% CI: 1.70-5.33), and living in the two districts (3.1 and 3.3) with worst conditions: large population and rates of homicides and shantytowns (aOR: 4.11; 95% CI: 1.79-9.46 and aOR: 5.35; 95% CI: 2.20-13.03, respectively). Our findings underscore the need for strengthening early identification and interventions for adolescents at high risk of unfavorable outcomes, especially those living in shantytowns.


Assuntos
Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/patologia , Adolescente , Antituberculosos/uso terapêutico , Brasil/epidemiologia , Criança , Coinfecção/epidemiologia , Coinfecção/patologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Razão de Chances , Estudos Retrospectivos , Fatores de Risco , Falha de Tratamento , Resultado do Tratamento
10.
Braz. j. infect. dis ; 23(6): 381-387, Nov.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1089317

RESUMO

ABSTRACT Setting: Treatment of tuberculosis (TB) can result in Drug-Induced Liver Injury (DILI) since hepatotoxic metabolites are formed during the biotransformation of isoniazid (INH).DILI can be related to the genetic profile of the patient. Single nucleotide polymorphisms in the CYP2E1 gene and GSTM1 and GSTT1 deletion polymorphisms have been associated with adverse events caused by INH. Objective: To characterize the genetic polymorphisms of CYP2E1, GSTT1 and GSTM1 in TB carriers. Design: This is an observational prospective cohort study of 45 patients undergoing treatment of TB. PCR-RFLP and multiplex-PCR were used. Results: The distribution of genotypic frequency in the promoter region (CYP2E1 gene) was: 98% wild genotype and 2% heterozygous. Intronic region: 78% wild genotype; 20% heterozygous and 2% homozygous variant. GST enzyme genes: 24% Null GSTM1 and 22% Null GSTT1. Patients with any variant allele of the CYP2E1 gene were grouped in the statistical analyses. Conclusion: Patients with the CYP2E1 variant genotype or Null GSTT1 showed higher risk of presenting DILI (p = 0.09; OR: 4.57; 95% CI: 0.75-27.6). Individuals with both genotypes had no increased risk compared to individuals with one genotype.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Tuberculose Pulmonar/tratamento farmacológico , Predisposição Genética para Doença/genética , Doença Hepática Induzida por Substâncias e Drogas/genética , Antituberculosos/efeitos adversos , Polimorfismo Genético , Tuberculose Pulmonar/enzimologia , Estudos Prospectivos , Citocromo P-450 CYP2E1 , Sistema Enzimático do Citocromo P-450/genética , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Família 2 do Citocromo P450 , Genótipo , Fígado/efeitos dos fármacos , Fígado/enzimologia , Antituberculosos/uso terapêutico
11.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 41(4): 316-323, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011503

RESUMO

Objective: To estimate the prevalence of major depressive episode (MDE) in patients with presumptive pulmonary tuberculosis (pre-PTB, defined by cough lasting ≥ 3 weeks) and compare it between patients with pulmonary tuberculosis (PTB) and without PTB. Methods: Patients with pre-PTB (n=260) were screened for depression using the Patient Health Questionnaire (PHQ-9). Those individuals with scores ≥ 10 were subsequently assessed with the depression module of the Mini International Neuropsychiatric Interview (MINI-Plus) to confirm diagnosis. Associations of categorical variables with PTB and MDE were calculated using the chi-square test and OR. Results: PTB was confirmed in 98 patients (37.7%). A high proportion of both groups (active PTB and no PTB) screened positive for depression (60.2 vs. 62.1%, respectively). Among 159 patients who screened positive for depression, a subset of 97 (61.0%) were further evaluated with the MINI-Plus; current MDE was confirmed in 54.6% (53/97). On univariate and multivariate analysis, female sex was the only factor associated with the diagnosis of current MDE (p = 0.04). Conclusion: The prevalence of MDE was high among individuals with prolonged respiratory symptoms, independent of PTB diagnosis. This is consistent with other studies of depression in primary care in Brazil.


Assuntos
Humanos , Masculino , Feminino , Adulto , Tuberculose Pulmonar/complicações , Depressão/complicações , Depressão/psicologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Atenção Primária à Saúde , Fatores Socioeconômicos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Brasil/epidemiologia , Prevalência , Estudos Transversais , Inquéritos e Questionários , Depressão/diagnóstico , Depressão/epidemiologia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/epidemiologia , Pessoa de Meia-Idade
12.
Clin Infect Dis ; 69(6): 1027-1035, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30481307

RESUMO

BACKGROUND: The role of genetic polymorphisms in latent tuberculosis (TB) infection and progression to active TB is not fully understood. METHODS: We tested the single-nucleotide polymorphisms (SNPs) rs5743708 (TLR2), rs4986791 (TLR4), rs361525 (TNFA), rs2430561 (IFNG) rs1143627 (IL1B) as risk factors for tuberculin skin test (TST) conversion or development of active TB in contacts of active TB cases. Contacts of microbiologically confirmed pulmonary TB cases were initially screened for longitudinal evaluation up to 24 months, with clinical examination and serial TST, between 1998 and 2004 at a referral center in Brazil. Data and biospecimens were collected from 526 individuals who were contacts of 177 active TB index cases. TST conversion was defined as induration ≥5 mm after a negative TST result (0 mm) at baseline or month 4 visit. Independent associations were tested using logistic regression models. RESULTS: Among the 526 contacts, 60 had TST conversion and 44 developed active TB during follow-up. Multivariable regression analysis demonstrated that male sex (odds ratio [OR]: 2.3, 95% confidence interval [CI]: 1.1-4.6), as well as SNPs in TLR4 genes (OR: 62.8, 95% CI: 7.5-525.3) and TNFA (OR: 4.2, 95% CI: 1.9-9.5) were independently associated with TST conversion. Moreover, a positive TST at baseline (OR: 4.7, 95% CI: 2.3-9.7) and SNPs in TLR4 (OR: 6.5, 95% CI: 1.1-36.7) and TNFA (OR: 12.4, 95% CI:5.1-30.1) were independently associated with incident TB. CONCLUSIONS: SNPs in TLR4 and TNFA predicted both TST conversion and active TB among contacts of TB cases in Brazil.


Assuntos
Predisposição Genética para Doença , Mycobacterium tuberculosis , Polimorfismo Genético , Receptor 4 Toll-Like/genética , Tuberculose/epidemiologia , Tuberculose/etiologia , Fator de Necrose Tumoral alfa/genética , Adulto , Alelos , Brasil/epidemiologia , Feminino , Genótipo , Humanos , Incidência , Testes de Liberação de Interferon-gama , Masculino , Razão de Chances , Polimorfismo de Nucleotídeo Único , Vigilância da População , Estudos Prospectivos , Fatores de Risco , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/transmissão , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/etiologia , Fluxo de Trabalho , Adulto Jovem
14.
Mutat Res ; 683(1-2): 43-9, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-19909761

RESUMO

N-Acetyltransferase 2 (NAT2) metabolizes a variety of xenobiotics that includes many drugs, chemicals and carcinogens. This enzyme is genetically variable in human populations and polymorphisms in the NAT2 gene have been associated with drug toxicity and efficacy as well as cancer susceptibility. Here, we have focused on the identification of NAT2 variants in Brazilian individuals from two different regions, Rio de Janeiro and Goiás, by direct sequencing, and on the characterization of new haplotypes after cloning and re-sequencing. Upon analysis of DNA samples from 404 individuals, six new SNPs (c.29T>C, c.152G>T, c.203G>A, c.228C>T, c.458C>T and c.600A>G) and seven new NAT2 alleles were identified with different frequencies in Rio de Janeiro and Goiás. All new SNPs were found as singletons (observed only once in 808 genes) and were confirmed by three independent technical replicates. Molecular modeling and structural analysis suggested that p.Gly51Val variant may have an important effect on substrate recognition by NAT2. We also observed that amino acid change p.Cys68Tyr would affect acetylating activity due to the resulting geometric restrictions and incompatibility of the functional group in the Tyr side chain with the admitted chemical mechanism for catalysis by NATs. Moreover, other variants, such like p.Thr153Ile, p.Thr193Met, p.Pro228Leu and p.Val280Met, may lead to the presence of hydrophobic residues on NAT2 surface involved in protein aggregation and/or targeted degradation. Finally, the new alleles NAT2*6H and NAT2*5N, which showed the highest frequency in the Brazilian populations considered in this study, may code for a slow activity. Functional studies are needed to clarify the mechanisms by which new SNPs interfere with acetylation.


Assuntos
Arilamina N-Acetiltransferase/química , Arilamina N-Acetiltransferase/genética , Haplótipos/genética , Modelos Moleculares , Polimorfismo de Nucleotídeo Único/genética , Tuberculose Pulmonar/genética , Acetilação , Brasil , Estudos de Casos e Controles , Humanos , Estrutura Molecular , Análise de Sequência , Tuberculose Pulmonar/enzimologia
15.
Mem. Inst. Oswaldo Cruz ; 103(5): 489-492, Aug. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-491979

RESUMO

The frequency of the Beijing genotype of Mycobacterium tuberculosis as a cause of tuberculosis (TB) in South America was determined by analyzing genotypes of strains isolated from patients that had been diagnosed with the disease between 1997 and 2003 in seven countries of the subcontinent. In total, 19 of the 1,202 (1.6 percent) TB cases carried Beijing isolates, including 11 of the 185 patients from Peru (5.9 percent), five of the 512 patients from Argentina (1.0 percent), two of the 252 Brazilian cases (0.8 percent), one of the 166 patients from Paraguay (0.6 percent) and none of the samples obtained from Chile (35), Colombia (36) and Ecuador (16). Except for two patients that were East Asian immigrants, all cases with Beijing strains were native South Americans. No association was found between carrying a strain with the Beijing genotype and having drug or multi-drug resistant disease. Our data show that presently transmission of M. tuberculosis strains of the Beijing genotype is not frequent in Latin America. In addition, the lack of association of drug resistant TB and infection with M. tuberculosis of the Beijing genotype observed presently demands efforts to define better the contribution of the virulence and lack of response to treatment to the growing spread of Beijing strains observed in other parts of the world.


Assuntos
Humanos , Mycobacterium tuberculosis/genética , Tuberculose Pulmonar/microbiologia , Impressões Digitais de DNA , Genótipo , Mycobacterium tuberculosis/classificação , Polimorfismo de Fragmento de Restrição , América do Sul/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar/epidemiologia
17.
Clin Diagn Lab Immunol ; 11(1): 94-7, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14715551

RESUMO

The purpose of the present study was to evaluate the usefulness of detection of serum immunoglobulin A (IgA) and IgG antibodies directed against the mycobacterial P-90 antigen for the diagnosis of active pulmonary tuberculosis (PTB) among symptomatic individuals and for the detection of Mycobacterium tuberculosis infections among close contacts of PTB patients. Two commercially available enzyme immunoassay (EIA) kits (IgA EIA-TB [EIA-IgA] and IgG EIA-TB [EIA-IgG]; Kreatech Diagnostics) were evaluated in a blinded fashion by using stored serum samples from 268 individuals, including 69 patients with PTB, 41 patients with diseases other than tuberculosis (TB), 12 subjects with healed PTB, 39 close contacts of PTB patients, and 107 healthy volunteers. For the EIA-IgA, the sensitivity was 74% and the specificity was 68% when a cutoff determined by a receiver operator characteristic curve was used. For the EIA-IgG, the sensitivity was 69% and the specificity was 64%. The EIA-IgA was positive for 54% of healthy close contacts of PTB patients but only 8% of healthy controls without contact with a PTB patient or a prior personal history of TB (P < 0.001). The relatively low sensitivities and specificities of these serologic tests make them poor tools for the diagnosis of PTB among patients with suspected PTB. However, the relatively high prevalence of positive EIA-IgA results among healthy close contacts of PTB patients warrants further evaluation of this test with close contacts and other populations at risk for recent M. tuberculosis exposure and development of disease.


Assuntos
Anticorpos Antibacterianos/sangue , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/imunologia , Adulto , Antígenos de Bactérias , Estudos de Casos e Controles , Busca de Comunicante , Humanos , Técnicas Imunoenzimáticas/métodos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Testes Sorológicos/estatística & dados numéricos
19.
Am J Respir Crit Care Med ; 167(5): 723-5, 2003 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-12598215

RESUMO

We prospectively evaluated the diagnostic yield of acid-fast bacilli smear and culture for Mycobacterium tuberculosis using sputum induction (SI) in the workup of patients with suspected pleural tuberculosis (TB) who were unable to produce sputum spontaneously. Of the 113 patients studied, a final diagnosis of pleural TB was made in 84 patients (71 HIV seronegative) and a final diagnosis of another disease in 29 patients. Histopathologic examination of the pleural biopsy tissue had the highest diagnostic yield (78%; 66/84). The bacteriologic yield was 62% (52/84) for the pleural tissue, 12% (10/84) for pleural fluid, and 52% (44/84) for sputum cultures obtained by SI. The yield of SI culture for M. tuberculosis was 55% (35/64) in patients with a normal radiograph (except for the pleural effusion) and 45% (9/20) in those with evidence of parenchymal disease suggestive of pulmonary TB (p = 0.6). The yield of sputum cultures obtained by SI is high in patients suspected of having pleural TB even in those cases with no pulmonary parenchymal abnormalities on the chest radiograph.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pleural/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Distribuição de Qui-Quadrado , Interpretação Estatística de Dados , Técnicas de Diagnóstico do Sistema Respiratório , Feminino , Soronegatividade para HIV , Soropositividade para HIV , Humanos , Masculino , Pessoa de Meia-Idade , Pleura/microbiologia , Pleura/patologia , Derrame Pleural/microbiologia , Estudos Prospectivos , Radiografia Torácica , Tuberculose Pleural/diagnóstico por imagem , Tuberculose Pleural/microbiologia , Tuberculose Pleural/patologia
20.
Pulmäo RJ ; 12(1): 10-16, 2003. tab
Artigo em Português | LILACS | ID: lil-714083

RESUMO

Objetivo: identificar fatores de risco associados à ocorrência de tuberculose pulmonar (TBP) paubacilar. Métodos: estudo transversal avaliando o resultado dos exames bacteriológicos de pacientes suspeitos de TBP atendidos em onze Centros Municipais de Saúde (CMS) na cidade do Rio de Janeiro, Brasil. Resultados: entre 1°. de Julho e 31 de Dezembro de 1996 foram entrecistados 423 pacientes com diagnóstico clínico-radiológico de TBP ativa. Noventa e quatro por cento (397/423) forneceram pelo menos duas amostras de escarro espontâneo para análise. A cultura foi positiva para Mycobacterium tuberculosis em 84% (333/397), com baciloscopia positiva em 64% (213/333) e baciloscopia negativa em 36% (121/333). Não se observou associação entre lesão pulmonar paucibacilar e gênero, vacinação com BCG, tempo de sintomas respiratórios, admissão prévia em prisão ou em asilos nos últimos 24 meses, comportamento sexual, uso de droga injetável, tratamento anti-TB no passado, contado com paciente tuberculoso pulmonar bacilífero nos últimos 12 meses, condições de moradia e residir em determinada área pragmática. Entretanto, a lesão pulmonar paucibacilar esteve associada significamente a escolaridade superior de 4 anos (1,87; 0,98-3,55; p=0,05), admissão prévia em hospital nos últimos 24 meses (2,53; 1,39-4,60; p=0,001) e sorologia positiva para infecção pelo vírus da imunodeficiência humana (HIV) (4,48;1,74-11,81; p=0,006). Conclusão: tuberculose pulmonar paubacilar deve ser considerada um problema em centros urbanos com elevada co-infecção /TB e HIV, onde a cultura para micobactéria e a testagem anti-HIV dvem ser disponibilizados para os pacientes com tais características.


Objective: to identify risk factors for negative sputum acid -fast bacilli smear among pulmonary tuberculosis (PTB) patients in CHC. Methods: cross sectional study, performed through bacteriological evaluation of mear negative/culture positive PTB cases attended in eleven Community Health Centers (CHC) in Rio de Janeiro City, Brazil. Results: from July 1st to December 31th, 1996, 423 patients with active PTB were interviewed and 397 had their spontaneous sputum evaluated. Afterwards 333 patients presented positive culture results for mycobacterium tuberculosis and among them 121 (36.2%) were smear negative. The agreement results (kappa value) between the first and the second sputa for smear acid-fast bacilli was moderate (0.49) but for culture was fair (0.31). No statistically significant association were identified among smear negative/culture positive results and be following variables: gender, BCG vaccionation, length of respiratory symptoms, previous admission at jails or at shelters in the previous 24 months, sexual behavior, intravenous drug use, anti-TB treatment in the past, contact with infectious PTB patients in the previous 12 months, living conditions and planning City Areas residence. Nevertheless, smear negative/culture positive PTB were observed as associated to 4.60; p=0.001) and, seropositivity for human immunodeficiency virus (HIV) (4.48; 1.74-11.81; p=0.006). Conclusion: Smear negative PTB should be considered a significant clinical problem, particularly in settings affected by dual HIV/TB epidemic. A wider availability of TB culture facilities should be pursued as well HIV testing for PTB suspect smear negative. So, to improve TB control in developing countries is urgently needed to update guidelines by both TB Control Program and AIDS Control Program.


Assuntos
Humanos , Masculino , Feminino , Estudos Transversais , Análise de Dados , Fatores de Risco , Tuberculose/diagnóstico
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