Antinuclear antibodies and PUVA photochemotherapy.

Sequential testing for antinuclear antibody (ANA) in a group of 99 patients receiving long-term methoxsalen (PUVA [methoxsalen plus ultraviolet light]) therapy showed positive tests for ANA in the serum samples of 42 patients. In 22 patients, the ANA was persistent; in seven patients, it was transient; and in the other 13 patients, it developed near the end of the observation period. A causal association between the occurrence of ANA and PUVA therapy is suggested by the incidence of ANA, its conversion from a negative to positive ANA test in 31 of 42 patients, and its statistically significant correlation with the duration of PUVA therapy. The ANA titers were 1:80 or greater in only 12 patients. The staining pattern was homogeneous in 39 patients, speckled in two patients, and nucleolar in one patient. In patients with a positive ANA test, the serologic tests for antibodies to DNA and extractable nuclear antigens were negative. Patients with positive ANA tests were significantly older than patients with negative ANA tests. Symptomatic systemic disease has not developed in any patient with a positive ANA test in this group.