Antinuclear antibodies during psoralens plus ultraviolet A (PUVA) therapy--are they worthwhile?

From 1979 to 1985, 497 patients with psoriasis were started on psoralens plus ultraviolet A (PUVA) therapy at Northwestern University. Two hundred sixty-nine of these received therapy for greater than 3 months and had at least two antinuclear antibody (ANA) determinations. We have found that the difference between the number of significantly positive ANAs pre-PUVA therapy (4 of 269) compared to post-PUVA therapy (16 of 269) was not statistically significant. Furthermore, of the patients who did develop a significantly positive ANA, not one was found to have any symptoms, signs, or laboratory evidence of systemic lupus erythematosus. We therefore suggest obtaining ANAs prior to initiating PUVA therapy and obtaining follow-up ANAs only if the initial ANA is significantly positive. Patients with pre-PUVA--positive ANAs can be started on PUVA therapy if there is no evidence of lupus erythematosus.