Antinuclear antibody studies in chronic cutaneous discoid lupus erythematosus.

The prevalence of antinuclar antibodies (ANA) in chronic cutaneous discoid lupus erythematosus (DLE) is influenced by both patient selection and test sensitivity. If one excludes serum samples from patients with DLE with a history suggesting extracutaneous disease and defines the significance of the ANA test by simultaneously testing serum samples from patients with well-characterized connective tissue diseases, then only a small percentage of the patients with DLE have ANA at significant titers. These patients with DLE do have a higher pervalence of positive ANA tests at low serum dilutions when compared with controls, but only a few have positive ANA tests at titers comparable to those seen in patients with active systemic connective tissue diseases.