RESUMO
OBJECTIVE: To examine the contribution of genetic and environmental factors to disease occurrence in 26 families with two or more members affected with systemic lupus erythematosus (SLE). METHODS: Genetic and environmental factors were examined by HLA-A, B, C/DR typing and by determining the presence of lymphocytotoxic antibodies (LCA) in patients and their consanguineous and non-consanguineous relatives. RESULTS: No association between SLE and HLA-A, B, C antigens was found. There was, however, a significant association with HLA-DR2 in white subjects with SLE. The most striking finding was that HLA sharing was increased among the affected members, suggesting genetic similarities. Seven of 14 sib pairs (50%) who had concordant SLE were HLA identical as opposed to an expected 25%. Another interesting finding was that 15/18 (83%) patients with SLE and 11/22 (50%) consanguineous relatives had LCA, while 1/9 (11%) spouses, and 2/42 (5%) healthy controls had these antibodies. CONCLUSION: Genetic factors have a role in the development and expression of SLE. Environmental factors may trigger the disease in genetically susceptible hosts.
Assuntos
Teste de Histocompatibilidade , Lúpus Eritematoso Sistêmico/genética , Adolescente , Adulto , Soro Antilinfocitário/imunologia , Distribuição Binomial , Estudos de Casos e Controles , Intervalos de Confiança , Consanguinidade , Feminino , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Antígenos HLA-C/imunologia , Antígenos HLA-DR/imunologia , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , CônjugesRESUMO
PROBLEM: To determine the presence of absence of subclinical autoimmunity in healthy women with first trimester recurrent spontaneous abortion (RSA), the sera of 72 healthy women with a history of three or more consecutive abortions were analyzed for the presence of antibodies to phospholipid and nuclear antigens. METHOD: Lupus anticoagulant was determined, as were antibodies to cardiolipin. An indirect immunofluorescent antinuclear test was performed and specific antinuclear antibodies to double-stranded DNA, ribonucleoprotein, Smith antigen, and Sjogren's syndrome A and B antigens were tested. RESULTS: Nine women (13.2%) had low levels of antinuclear antibodies, none of which were specific. Four women (5.6%) had moderate to high levels of aCL antibodies. CONCLUSION: We conclude that the prevalence of aCLs and antinuclear antibodies in healthy women with first trimester RSA is low. Subclinical autoimmunity is not a common cause of first trimester RSA.
