Treating prolactinoma can prevent autoimmune diseases.

Prolactin (PRL) is a pleiotropic hormone; in addition to a wide variety of endocrine effects, PRL also exhibits immunostimulating effects. Therefore, there is increasing evidence linking PRL with a large number of systemic and organ specific autoimmune diseases. Herein, we report the case of an adolescent girl diagnosed with multiple sclerosis (MS) occurring in the context of untreated prolactinoma evolving since childhood. This raises the exciting question of the involvement of PRL in the pathogenesis of MS. It is likely that early treatment of hyperprolactinemia in this case would have significantly reduced the risk of developing MS or even prevented its occurrence.