Procainamide‐induced serologic changes in asymptomatic patients

Abstract

Abstract Serologic findings in cardiac patients who had no manifestations of drug‐induced lupus and who had been taking procainamide for 6 weeks or more were compared to a similar group receiving quinidine, and a series of age‐ and sex‐matched controls. Significant changes occurred only in the group of 22 patients treated with procainamide (p < 0.01). LE cell tests were positive in 12 (55 per cent). Antidesoxyribonucleoprotein (anti‐DNP) tests were positive in 15 (68 per cent) and anti‐DNA in 8 (36 per cent). A positive LE cell test, anti‐DNP, or anti‐DNA reaction was found in 17 (77 per cent).