3- HYPERPITUITARISM - HYPERPROLACTINEMIA

• Hyperpituitarism - Hyperprolactinemia

  Condition where there is excessive production of prolactin hormone
• Causes of hyperprolactinemia

  • Adenoma of pituitary (prolactinoma)
  • Primary hypothyroidism (increase in TRH à stimulates prolactin secretion)
  • Acromegaly (prolactin co-secreted w/ GH)
  • PCOS
  • Drugs (estrogen, cimetidine, metoclopramide, phenothiazines, antipsychotics, TCAs, opioids, verapamil, methyldopa)
  • Compression on the pituitary stalk causing dissociation & discontinuation of dopamine delivery to Ant. pituitary à loss of the inhibitory effect à high prolactin
  • Physiological causes: pregnancy, intense exercise, renal insufficiency & increased chest wall stimulation
• Clinical features of hyperprolactinemia

  • Galactorrhea
  • Hypogonadism (Female: amenorrhea & infertility, Male: erectile dysfunction, decreased libido, & infertility)
  • Headaches & visual field defects (if prolactinoma)
• Diagnosis of hyperprolactinemia

  1. Perform serum prolactin first

  2. If high, proceed with TFT, pregnancy test, BUN/Creatinine (kidney disease elevates prolactin) & LFT (cirrhosis elevates prolactin)

  3. MRI of pituitary done after: High prolactin confirmed, Secondary causes excluded, Patient is not pregnant
• Treatment of hyperprolactinemia

  • Medical: dopamine agonists (cabergoline, bromocriptine)
  • Surgical: transsphenoidal resection of the pituitary adenoma (appropriate when no response to medications)
  • Radiation rarely needed
  • Asymptomatic hyperprolactinemia does not need treatment
• In prolactinoma

  Treatment of choice #1 is medical & #2 surgical
• In Acromegaly

  Treatment of choice #1 is surgical & #2 medical
• Always exclude pregnancy in any women with high prolactin