Hyperprolactinemia
Elevated prolactin hormone levels, usually from a benign pituitary tumor, causing milky nipple discharge and infertility.
Emergency Management: Pituitary apoplexy. Requires stat IV Hydrocortisone 100 mg and urgent neurosurgery.
Hyperprolactinemia is the persistent elevation of serum prolactin. The most common pathological cause is a prolactinoma, a benign pituitary adenoma secreting prolactin, leading to hypogonadism and galactorrhea.
Detailed Overview
Prolactin is tonically inhibited by hypothalamic dopamine. Loss of this inhibition (via stalk compression or dopamine antagonist drugs) or autonomous tumor secretion raises prolactin. High prolactin suppresses GnRH, causing hypogonadotropic hypogonadism. First-line therapy is medical (dopamine agonists), uniquely highly effective at shrinking these tumors.
Epidemiology & Demographics
Prolactinomas account for 40% of pituitary tumors. More common in females aged 20-50 (microadenomas), while males often present later with macroadenomas.
Etiological Mechanism
Prolactinoma, pregnancy, primary hypothyroidism, and dopamine antagonist medications.
Primary Causes
Prolactinoma
Medications (antipsychotics, metoclopramide)
Prolactinomas are monoclonal expansions of lactotrophs. Excess prolactin binds to receptors on the hypothalamus, suppressing pulsatile GnRH release. This decreases LH/FSH, shutting down gonadal steroidogenesis (estradiol/testosterone). Macroadenomas (>10mm) can compress the optic chiasm.
Diagnostic Criteria & Guidelines
Persistently elevated prolactin without physiologic cause, combined with MRI evidence of a pituitary adenoma.
Cabergoline (D2 agonist) 0.25 mg PO twice weekly, titrated to normalize prolactin and shrink tumor.
Second-Line & Adjunctive Therapy
Bromocriptine 1.25 mg PO daily. Endoscopic transsphenoidal surgery if resistant/intolerant to meds.
Surgical & Procedural Management
Endoscopic endonasal transsphenoidal adenomectomy.
Patient Counseling & Advice
Warn about nausea and orthostatic hypotension with cabergoline. Rare risk of impulse control disorders. Fertility often returns quickly, so use contraception if pregnancy is not desired.
Follow-Up & Monitoring Schedule
Prolactin levels every 1-2 months initially. Repeat MRI at 1 year. Visual field tests if macroadenoma.
Preventive Strategies
None.
Excellent. 80% achieve normal prolactin and tumor shrinkage on cabergoline.