Antiprolactin autoantibodies in systemic lupus erythematosus: frequency and correlation with prolactinemia and disease activity.

The presence of anti-PRL autoantibodies was associated with hyperprolactinemic status and high serum PRL levels; these data suggest that anti-PRL autoantibodies could be the cause of hyperprolactinemia in a subset of patients with SLE. An increase in serum PRL levels proved to be an important independent factor related to lupus activity, but there was no relationship between anti-PRL autoantibodies and lupus activity.