A 32-year-old female presents with a 6-month history of irregular menstrual cycles and galactorrhea (spontaneous milk production from the breasts). She reports that her periods have become less frequent over the past few months, with some cycles being skipped altogether. The patient has no history of pregnancy, breastfeeding, or recent significant weight changes. She also complains of mild headaches, particularly in the morning, and occasional visual disturbances, including blurring of vision. She denies any significant changes in libido or any other systemic symptoms.

The patient is not on any medications, and there is no history of trauma or recent infections. Upon physical examination, she appears well-nourished and in no acute distress. There is no evidence of galactorrhea on physical examination, and breast examination is unremarkable. However, during palpation, she notes tenderness in the upper abdomen, but no masses are palpated. Neurological examination is normal, but visual field testing reveals some slight defects in the superior visual fields bilaterally.

Blood work reveals:

Prolactin level: 75 ng/mL (normal range: 2-29 ng/mL)

Thyroid function: Normal

HCG: Negative

LH/FSH ratio: Slightly low

An MRI of the brain shows an incidental finding of a pituitary mass, suspected to be a pituitary adenoma.

Diagnosis: Hyperprolactinemia, likely secondary to a pituitary adenoma (prolactinoma).

Management plan:

Initiation of dopamine agonists (cabergoline) to lower prolactin levels

Repeat MRI in 3-6 months to assess the size of the pituitary adenoma

Referral to an endocrinologist for ongoing management

Outcome: The patient was started on cabergoline, and after a few weeks of treatment, she noticed improvement in her symptoms, with the return of regular menstrual cycles and the cessation of galactorrhea. Follow-up imaging showed a reduction in the size of the pituitary mass.