Revista Brasileira de Reumatologia (Jun 2010)
Prevalência de deficiência de IgA em pacientes adultos com lúpus eritematoso sistêmico e estudo de sua associação com perfil clínico e de autoanticorpos Prevalence of IgA deficiency in adult Systemic Lupus Erythematosus and the study of the association with its clinical and autoantibody profiles
Abstract
INTRODUÇÃO: A deficiência de imunoglobulina A (DIgA) é a imunodeficiência primária mais comum e pode levar a quadros frequentes de infecções. Sua associação com lúpus eritematoso sistêmico (LES) é de extrema importância, dada a alta morbidade e mortalidade que as infecções causam nestes pacientes. OBJETIVOS: Demonstrar a prevalência da deficiência de IgA entre pacientes portadores de LES do sul do Brasil. Comparar o perfil clínico e de autoanticorpos entre pacientes lúpicos com e sem DIgA. PACIENTES E MÉTODOS: Estudo incluindo 189 pacientes com LES submetidos à dosagem sérica de IgA pelo método de nefelometria, sendo considerados deficientes aqueles com IgA inferior à 50 mg/dL. Dados demográficos, de perfil clínico [artrite, psicoses, convulsões, acidentes vasculares encefálicos (AVE), serosites, hemólise, leucopenia, plaquetopenia, nefrite] e de autoanticorpos [FAN, anti-SSA/Ro, anti-SSB/La, anti-Sm, anti-DNA, anti-RNP, LAC (anticoagulante lúpico) e aCL (anticorpos anticardiolipina)] IgG e IgM foram obtidos pela revisão de prontuários. Como controle, foram utilizados dados da literatura de um estudo feito na mesma área geográfica. Os dados foram analisados por tabelas de frequência e contingência aplicando-se os testes de Qui-quadrado, Fisher e Mann-Whitney. RESULTADOS: Foram encontrados 11 (6,17%) pacientes com a DIgA (P INTRODUCTION: IgA deficiency (IgAD) is the most common primary immunodeficiency, which can cause frequent infections. The association of IgA deficiency with systemic lupus erythematosus (SLE) is very important because of the high morbidity and mortality rates of infections in patients with this disease. OBJECTIVES: To study the prevalence of IgA deficiency in SLE patients from southern Brazil and to compare the clinical and autoantibody profiles of SLE patients with and without IgA deficiency. PATIENTS AND METHODS: One hundred and eighty-nine SLE patients were submitted to serum IgA measurement by nephelometry. Levels of IgA below 50mg/dL were considered to be IgAD. Demographic data, clinical profile (presence of arthritis, psychosis, seizures, stroke, serositis, hemolytic anemia, leucopenia, thrombocytopenia, and nephritis) and autoantibody profiles (ANA, anti-Ro, anti-La, anti-Sm, anti-DNA, anti-RNP, lupus anticoagulant, and anticardiolipin IgG and IgM) were obtained from reviewing medical records. As control, we used literature data from another study performed in the same geographical area. Data were analyzed through contingency and frequency tables, applying the Chi-square, Fisher, and Mann Whitney tests. RESULTS: IgA deficiency was found in 11 (6.17%) patients (P < 0.001 in relation to controls). The association between IgA deficiency and clinical or autoantibody profile was not significant. CONCLUSION: We concluded that a higher prevalence of IgA deficiency was observed in lupus patients than in controls. Deficiency of IgA did not have any particular laboratory or clinical effects on this population.
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