Normal distribution of acetylation phenotypes in systemic lupus erythematosus.

Previous reports have indicated that idiopathic systemic lupus erythematosus (SLE), like drug-induced lupus, is more frequent in "slow" hepatic acetylators. Using dapsone acetylation rate to determine phenotypes, we found that of the 18 SLE patients studied, 9 were fast acetylators, 8 were slow, and 1 was indeterminate. This result (53% fast) is similar to acetylator phenotypes in our normal controls (50% fast) and in the population at large (52%).