Hypersensitivity to Deoxyribonucleic Acid In Cutaneous Disease

Abstract

Forty of 115 patients reacted to intradermal deoxyribonucleic acid (DNA), demonstrating erythema, edema, and induration of the test site within 24 hours; an additional four patients reacted to the original antigen but not a new one. Positive reactions were about twice as frequent in untreated patients as in patients with similar disease who were receiving steroid or antimalarial drugs. Five patients were tested before and after such therapy; in each instance the reaction was abolished or diminished. No correlation seemed to exist between reaction to DNA and the presence of the LE or the rheumatoid factor, or the duration of severity of the disease. Serum was obtained from ten consecutive unselected patients and from five additional, selected patients with necrotizing vasculitis. An immunodiffusion agar technique did not demonstrate precipitating factors directed against DNA in these 15 sera. An indirect immunofluorescent technique employing the same sera demonstrated antinuclear factors in all patients with systemic lupus erythematosis (SLE) and disseminated lupus erythematosus (DLE) and in one paltient with necrotizing (allergic) vasculitis. There is no conclusive evidence that hypersensitivity to DNA exists in collagen diseases, necrotizing vasculitis, and other nonsuppurative inflammatory diseases studied. Intraderma testing employing DNA is a moderately sensitive but poorly specific means for detecting apparent delayed (cellular) hypersensitivity to nucleoprotein. However, one must not imply that such hypersensitivity, if it exists, is essential to the diseases studied. The test may have some merit in screening large population groups but lacks reliability since some patients with clinically active, untreated disease do not react.