RESUMO
SETTING: Arkansas, USA. OBJECTIVE: To investigate the relationship between an increase in the proportion of cases with advanced disease at first diagnosis and the recently observed slowing of the decline in tuberculosis (TB) incidence in low-incidence US states. DESIGN: We conducted descriptive statistical analyses of de-identified surveillance data of 1246 culture-confirmed TB patients reported in Arkansas during 1996-2013. We then fitted stepwise, multivariate logistic regression models to identify predictors for advanced disease at diagnosis, defined as having either smear-positive sputum or lung cavitation. RESULTS: From 1996 to 2013, the proportion of new cases with positive sputum smear and cases with lung cavitation increased from 51.6% to 75% and from 37.7% to 50%, respectively. Patients diagnosed during 2006-2013 were more likely to have positive sputum smears (adjusted odds ratio [aOR] 2.55, 95%CI 1.95-3.35) or lung cavitation (aOR 1.49, 95%CI 1.14-1.95) than those diagnosed during 1996-2005. During 1996-2013, age 15-64 years and excessive alcohol use were predictive of positive sputum smear or lung cavitation. CONCLUSION: Measures to reduce the proportion of cases with advanced disease at first diagnosis may be helpful to achieve further decline in TB incidence in low-incidence settings.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Mycobacterium tuberculosis/isolamento & purificação , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Fatores Etários , Idoso , Arkansas/epidemiologia , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/patologia , Adulto JovemRESUMO
The Mycobacterium tuberculosis genome contains four phospholipase C (PLC)-encoding genes, designated plcA, plcB, plcC, and plcD, respectively. Each of the four genes contributes to the overall PLC activity of M. tuberculosis. PLC is hypothesized to contribute to M. tuberculosis virulence. Infection of M. tuberculosis strains carrying a truncated plcD gene is associated with the occurrence of extrathoracic tuberculosis. However, whether the other three plc genes are also associated with extrathoracic tuberculosis remains to be assessed. We investigated the insertion- and deletion-associated genetic diversity in all four plc genes among 682 epidemiologically and clinically well-characterized M. tuberculosis clinical isolates using PCR, DNA sequencing, and Southern hybridization. Two hundred sixty-six (39%) of the 682 isolates had an interruption in at least one of the four plc genes, most often associated with an IS6110 insertion. The plcD gene interruption was the most common: it was observed in 233 (34%) of the isolates, compared to 4.7%, 4.1%, and 5.9% for plcA, plcB, and plcC gene interruption, respectively. The association between the plc gene genotypes and disease presentation was adjusted for clustering using generalized estimating equations for both bivariate and multivariate analyses. After controlling for the genotypes of the plcABC genes and the host-related risk factors, interruption in the plcD gene remained significantly associated with extrathoracic tuberculosis (odds ratio, 3.27; 95% confidence interval, 1.32 to 8.14). The data suggest that the plcD gene might play a more important role in the pathogenesis of thoracic TB than it does in the pathogenesis of extrathoracic TB.
Assuntos
Elementos de DNA Transponíveis , Deleção de Genes , Mycobacterium tuberculosis/patogenicidade , Polimorfismo Genético , Tuberculose/fisiopatologia , Fosfolipases Tipo C/genética , Proteínas de Bactérias/genética , Genótipo , Humanos , Dados de Sequência Molecular , Mutagênese Insercional , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Análise de Sequência de DNA , Tuberculose/epidemiologia , Tuberculose/microbiologiaRESUMO
Restriction fragment length polymorphism (RFLP) analysis of IS6110 is commonly used to DNA fingerprint Mycobacterium tuberculosis. However, low-copy (< or =5) IS6110 M. tuberculosis strains are poorly differentiated, requiring secondary typing. When spoligotyping was used as the secondary method, only 13% of Maryland culture-positive tuberculosis (TB) patients with low-copy IS6110-spoligotyped clustered strains had epidemiologic linkages to another patient, compared to 48% of those with high-copy strains clustered by IS6110 alone (P < 0.01). Spoligotyping did not improve a population-based molecular epidemiologic study of recent TB transmission.
Assuntos
Impressões Digitais de DNA , Elementos de DNA Transponíveis/genética , Dosagem de Genes , Mycobacterium tuberculosis/classificação , Tuberculose Pulmonar/epidemiologia , Idoso , Técnicas de Tipagem Bacteriana , Humanos , Mycobacterium tuberculosis/genética , Oligonucleotídeos/análise , Polimorfismo de Fragmento de Restrição , Tuberculose Pulmonar/microbiologiaRESUMO
The objective was to determine the HIV-1 seroprevalence in expectant women in Kampala. HIV-1 antibody status (by ELISA -Cambridge Biotech; with comformatory ELISA-Wellcozyme on positives); obstetric and socio-demographic characteristics were determined on a random proportionate to-size sample of 1002 expectant consenting women seeking care at 11 prenatal units in Kampala between august and December of 1993. HIV-1 age-specific rates were determined. Chi-square analysis; tests for linear trend in rates and 95CI were used to determine significance of seroprevalence rates. Results showed overall seroprevalence of HIV-1 for the study population (mean age = 22.4 years; range = 14 - 42 years) was 20.5(95CI:18.0; 23.1); with the highest age-specific rate of 28.55 occurring at 20 - 22 years. An increasing trend of rates was observed between 14 - 24 years (p0.0001); followed; thereafter; by a decreasing trend (p
RESUMO
The objective was to determine the HIV-1 seroprevalence in expectant women in Kampala. HIV-1 antibody status (by ELISA -Cambridge Biotech; with comformatory ELISA-Wellcozyme on positives); obstetric and socio-demographic characteristics were determined on a random proportionate to-size sample of 1002 expectant consenting women seeking care at 11 prenatal units in Kampala between august and December of 1993. HIV-1 age-specific rates were determined. Chi-square analysis; tests for linear trend in rates and 95CI were used to determine significance of seroprevalence rates. Results showed overall seroprevalence of HIV-1 for the study population (mean age