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Association between HLA class II antigens and the chronic fatigue immune dysfunction syndrome.

The chronic fatigue immune dysfunction syndrome (CFIDS) is a major subgroup of the chronic fatigue syndrome (CFS). CFIDS is characterized by a protean group of signs and symptoms described frequently after an antecedent viral illness. Despite a plethora of pseudonyms used in the literature since the late nineteenth century [1, 2] and the recent classification of this syndrome by the Centers for Disease Control and Prevention (CDC; Atlanta) [3], controversy abounds over both the etiology and pathogenic mechanism(s) involved. Nonetheless, we [4] and other investigators [5, 6] have reported a strong association between immune dysfunction and a serological viral reactivation pattern among patients in this group. This finding appeared similar to that for a variety of conditions, such as chronic active hepatitis [7], juvenile rheumatoid arthritis, and systemic lupus erythematosus [8], in which a definite association between a particular HLA-DR/DQ haplotype and increased disease frequency has been reported. We thus elected to examine a cohort of patients with CFIDS, as defined by the CDC, with use of HLA-DR/DQ typing. The frequency of HLA class II antigens in this group was compared with that among a large group of closely matched controls.