MON-258 Hyperprolactinemia: An Unusual Initial Presenting Manifestation of Multiple Sclerosis

Hyperprolactinemia and multiple sclerosis (MS) have a direct relationship and hyperprolactinemia may precede clinical signs of MS as a heralding manifestation of disease. Prolactin has significant pro-inflammatory effects in addition to its lactotrophic properties and can also lower the body’s immune tolerance, inducing autoimmunity. High levels of prolactin have been thought to contribute to the inflammation of multiple sclerosis. However, elevated levels of prolactin, especially in pregnant women, can be protective for MS patients and induce remission. Prolactin is neuroregenerative and stimulates the precursors for oligodendrocytes, the cells responsible for myelination. Our hypothesis is that an elevated prolactin level detected during an MS flare should not be treated with dopamine agonist, but rather allowed to decrease as the MS improves with treatment. Case Presentation A 24 year old woman with a history of marijuana use is referred to our clinic for elevated prolactin levels associated with galactorrhea for 3 months duration. In addition to marijuana use, patient was also sexually active and having regular menses, with menarche at age 11 years old. On physical exam, the patient was found to have bilateral nipple discharge with stimulation, and visual fields were intact to confrontation. At the time of referral, the patient’s prolactin was 92.3 ng/dL (4.8−23.3 ng/mL) TSH was normal, and pregnancy test negative.An MRI showed multiple areas of enhancement compatible with active demyelination, concerning for multiple sclerosis. The pituitary gland was enlarged, without evidence of adenoma. A follow up prolactin level was 101 ng/dL and upon further discussion, patient also admitted to some “funny feeling” and weakness in her right hand and a feeling of being “off balance” diagnosed as a left ear infection. Patient was advised to seek urgent treatment for multiple sclerosis. She was admitted, where she was seen by neurology and diagnosed with relapsing remitting multiple sclerosis. She was initially treated with a course of IV methylprednisolone. She was discharged after this course and followed with neurology as an outpatient. For a few months our patient went into remission and her prolactin improved to 24 ng/dL. A few months later, she had a significant increase in her prolactin to 71.5 ng/dL accompanied by evidence of disease progression on MRI and symptoms of weakness and falls. Neurologists changed her medication from Copaxone to Tecfidera and patient improved clinically and has not had any further flares. Notably, she never received any dopaminergic agent to treat her prolactin level, which improved significantly.Our case illustrates that prolactin may be a disease marker in the acute phase of MS and can be restorative. Further more it will improve when the MS is treated and we should not use any dopamine agonist.