Relatedness and HLA-DRB1 typing may discriminate the magnitude of the genetic susceptibility to tuberculosis using a household contact model


Autoria(s): LUCENA-SILVA, N.; BALIZA, M. D.; MARTINS, A. E. S.; DEGHAIDE, N. H. S.; TEIXEIRA, K. M.; RODRIGUES, L. C.; XIMENES, R.; DONADI, E. A.; ALBUQUERQUE, M. d F. P. M. de
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

18/04/2012

18/04/2012

2010

Resumo

Background Tuberculosis clusters in families may be due to increased household exposure, shared genetic factors, or both. Household contact studies are useful to control exposure because socioeconomic and environmental conditions are similar to all subjects, allowing the evaluation of the contribution of relatedness to disease development. Methods In this study, the familial aggregation of tuberculosis using relatedness and a specific inherited marker (HLA-DRB1) was evaluated. Fifty families, which had at least two cases of tuberculosis diagnosed within the past 5 years, were selected from a cohort of tuberculosis carried out in Recife, Brazil. The first case diagnosed was considered to be a primary case. The secondary attack rate of tuberculosis in household contacts was estimated according to the degree of relatedness. The relative risk of having tuberculosis based on the degree of relatedness household and the population attributable fraction to relatedness were also estimated. HLA-DRB1 typing and attributable etiologic/preventive fractions were calculated among sick and healthy household contacts. Results Compared to unrelated contacts, the relative risk for tuberculosis adjusted for age was 1.38 (95% CI 0.86 to 2.21). Relatedness contributed 23% to the development of tuberculosis at the population levels. The HLA-DRB1*04 allele group (OR = 2.44; p =0.0324; etiologic fraction =0.15) was overrepresented and the DRB1*15 allele group (OR=0.48; p=0.0488; protective fraction=0.19) was underrepresented among household contacts exhibiting tuberculosis. The presence of DRB1 shared alleles between primary cases and their contacts was a risk factor for tuberculosis (p=0.0281). Conclusion This household contact model together with the utilisation of two genetic variables permitted the evaluation of genetic factors contributing towards tuberculosis development.

CNPq (Brazilian Council for Scientific and Technological Development)

Identificador

JOURNAL OF EPIDEMIOLOGY AND COMMUNITY HEALTH, v.64, n.6, p.513-517, 2010

0143-005X

http://producao.usp.br/handle/BDPI/15292

10.1136/jech.2008.086801

http://dx.doi.org/10.1136/jech.2008.086801

Idioma(s)

eng

Publicador

B M J PUBLISHING GROUP

Relação

Journal of Epidemiology and Community Health

Direitos

closedAccess

Copyright B M J PUBLISHING GROUP

Palavras-Chave #HUMAN-LEUKOCYTE ANTIGEN #CLASS-II ALLELES #PULMONARY TUBERCULOSIS #RISK-FACTORS #POLYMORPHISMS #ASSOCIATION #FREQUENCY #AFRICA #FAMILY #POPULATION #Public, Environmental & Occupational Health
Tipo

article

original article

publishedVersion