Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
1.
J Infect Dis ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38820119

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38170196

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-36186793

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35033658

RESUMEN

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.


Asunto(s)
Estado Prediabético , Tuberculosis Pulmonar , Tuberculosis , Humanos , Perú/epidemiología , Estado Prediabético/complicaciones , Estado Prediabético/epidemiología , Resultado del Tratamiento , Tuberculosis/complicaciones , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/epidemiología
5.
J Infect Dis ; 225(4): 617-626, 2022 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-34651642

RESUMEN

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.


Asunto(s)
Diabetes Mellitus , Estado Prediabético , Tuberculosis , Antituberculosos/uso terapéutico , Estudios de Cohortes , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología , Humanos , Estado Prediabético/complicaciones , Estado Prediabético/tratamiento farmacológico , Estudios Prospectivos , Resultado del Tratamiento , Tuberculosis/complicaciones , Tuberculosis/tratamiento farmacológico
6.
Microbiol Spectr ; 9(3): e0116321, 2021 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-34851140

RESUMEN

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.


Asunto(s)
Ensayos de Liberación de Interferón gamma/métodos , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/epidemiología , Tamizaje Masivo/métodos , Mycobacterium tuberculosis/aislamiento & purificación , Brasil/epidemiología , Estudios de Cohortes , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Tuberculosis Latente/tratamiento farmacológico , Estudios Prospectivos , Control de Calidad , Reproducibilidad de los Resultados , Manejo de Especímenes/métodos , Tuberculosis/tratamiento farmacológico , Tuberculosis/prevención & control
7.
Front Med (Lausanne) ; 8: 706689, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34386510

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-33197582

RESUMEN

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.


Asunto(s)
Tuberculosis/terapia , Adulto , Brasil/epidemiología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Tuberculosis/complicaciones , Tuberculosis/epidemiología
9.
Am J Trop Med Hyg ; 103(6): 2492-2500, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32959763

RESUMEN

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.


Asunto(s)
Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/patología , Adolescente , Antituberculosos/uso terapéutico , Brasil/epidemiología , Niño , Coinfección/epidemiología , Coinfección/patología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Humanos , Masculino , Oportunidad Relativa , Estudios Retrospectivos , Factores de Riesgo , Insuficiencia del Tratamiento , Resultado del Tratamiento
10.
Braz. j. infect. dis ; Braz. j. infect. dis;23(6): 381-387, Nov.-Dec. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1089317

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto Joven , Tuberculosis Pulmonar/tratamiento farmacológico , Predisposición Genética a la Enfermedad/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Antituberculosos/efectos adversos , Polimorfismo Genético , Tuberculosis Pulmonar/enzimología , Estudios Prospectivos , Citocromo P-450 CYP2E1 , Sistema Enzimático del Citocromo P-450/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Familia 2 del Citocromo P450 , Genotipo , Hígado/efectos de los fármacos , Hígado/enzimología , Antituberculosos/uso terapéutico
11.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; Braz. J. Psychiatry (São Paulo, 1999, Impr.);41(4): 316-323, July-Aug. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1011503

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Tuberculosis Pulmonar/complicaciones , Depresión/complicaciones , Depresión/psicología , Trastorno Depresivo Mayor/complicaciones , Trastorno Depresivo Mayor/psicología , Atención Primaria de Salud , Factores Socioeconómicos , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/epidemiología , Brasil/epidemiología , Prevalencia , Estudios Transversales , Encuestas y Cuestionarios , Depresión/diagnóstico , Depresión/epidemiología , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/epidemiología , Persona de Mediana Edad
12.
Clin Infect Dis ; 69(6): 1027-1035, 2019 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-30481307

RESUMEN

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.


Asunto(s)
Predisposición Genética a la Enfermedad , Mycobacterium tuberculosis , Polimorfismo Genético , Receptor Toll-Like 4/genética , Tuberculosis/epidemiología , Tuberculosis/etiología , Factor de Necrosis Tumoral alfa/genética , Adulto , Alelos , Brasil/epidemiología , Femenino , Genotipo , Humanos , Incidencia , Ensayos de Liberación de Interferón gamma , Masculino , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Vigilancia de la Población , Estudios Prospectivos , Factores de Riesgo , Prueba de Tuberculina , Tuberculosis/diagnóstico , Tuberculosis/transmisión , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/etiología , Flujo de Trabajo , Adulto Joven
14.
Mutat Res ; 683(1-2): 43-9, 2010 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-19909761

RESUMEN

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.


Asunto(s)
Arilamina N-Acetiltransferasa/química , Arilamina N-Acetiltransferasa/genética , Haplotipos/genética , Modelos Moleculares , Polimorfismo de Nucleótido Simple/genética , Tuberculosis Pulmonar/genética , Acetilación , Brasil , Estudios de Casos y Controles , Humanos , Estructura Molecular , Análisis de Secuencia , Tuberculosis Pulmonar/enzimología
15.
Mem. Inst. Oswaldo Cruz ; 103(5): 489-492, Aug. 2008. graf, tab
Artículo en Inglés | LILACS | ID: lil-491979

RESUMEN

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.


Asunto(s)
Humanos , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/microbiología , Dermatoglifia del ADN , Genotipo , Mycobacterium tuberculosis/clasificación , Polimorfismo de Longitud del Fragmento de Restricción , América del Sur/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Pulmonar/epidemiología
17.
Clin Diagn Lab Immunol ; 11(1): 94-7, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14715551

RESUMEN

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.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Tuberculosis Pulmonar/diagnóstico , Tuberculosis Pulmonar/inmunología , Adulto , Antígenos Bacterianos , Estudios de Casos y Controles , Trazado de Contacto , Humanos , Técnicas para Inmunoenzimas/métodos , Técnicas para Inmunoenzimas/estadística & datos numéricos , Persona de Mediana Edad , Mycobacterium tuberculosis/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Pruebas Serológicas/estadística & datos numéricos
19.
Am J Respir Crit Care Med ; 167(5): 723-5, 2003 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-12598215

RESUMEN

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.


Asunto(s)
Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología , Tuberculosis Pleural/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Distribución de Chi-Cuadrado , Interpretación Estadística de Datos , Técnicas de Diagnóstico del Sistema Respiratorio , Femenino , Seronegatividad para VIH , Seropositividad para VIH , Humanos , Masculino , Persona de Mediana Edad , Pleura/microbiología , Pleura/patología , Derrame Pleural/microbiología , Estudios Prospectivos , Radiografía Torácica , Tuberculosis Pleural/diagnóstico por imagen , Tuberculosis Pleural/microbiología , Tuberculosis Pleural/patología
20.
Pulmäo RJ ; 12(1): 10-16, 2003. tab
Artículo en Portugués | LILACS | ID: lil-714083

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , Estudios Transversales , Análisis de Datos , Factores de Riesgo , Tuberculosis/diagnóstico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA