Anti-ribonucleoprotein antibodies in inflammatory rheumatic diseases.

Of 472 consecutive patients with inflammatory rheumatic diseases attending a unit responsible for the treatment of rheumatoid diseases, only 12 patients were found to have anti-ribonucleoprotein (RNP) antibodies. Of these, 5 patients fulfilled the criteria for the diagnosis of systemic lupus erythematosus (SLE) and 7 those of rheumatoid arthritis. Joint symptoms were the predominant clinical features and caused severe deformities requiring operations in most cases. One anti-RNP-positive SLE patient died of chronic active hepatitis.