The ribonucleic acid (RNA) skin test in systemic lupus erythematosus and other connective tissue diseases.

A series of 65 patients with different autoimmune diseases was examined using different RNA-solutions for intradermal skin tests. Clinically positive results were obtained most often in patients with mixed connective tissue disease but quite often also in patients with systemic lupus erythematosus and progressive systemic sclerosis or with some symptoms of an automimmune nature. The histological examination of the biopsies from the test sites revealed that there was no correlation between the clinically positive tests and the histological criteria usually used as a sign of a positive test.