Hyperprolactinaemia

Question 1

Hyperprolactaemia

Answer 1

Higher than normal prolactin levels in the blood

Question 2

Effects of prolactin

Answer 2

Men : Prolactin decreases testosterone production
Women : During pregnancy, 
(1)->increases levels of oestrogen 
->stimulates high prolactin levels
-> Alveolar cells in breasts stimulated
-> Alveolar cells divide and enlarge
-> Lactogenesis - milk is produced

(2)-> Inhibit release of gonadotropin releasing hormone
-> Decrease LH and FSH hormone level
-> Decrease Oestrogen
-> STOPS OVULATION AND MENSTRUATION
( why women do not have periods during pregnancy)
-

Question 3

How prolactin levels are kept in check

Answer 3

1. Secretes dopamine
   ( prolactin inhibiting factor)
   - Inhibits release of prolactin
2. Secretes thyrotropin releasing hormone (PRL)
   - Stimulates prolactin release
   - Signals hypothalamus to release more dopamine // decreasing its own production

Question 4

Causes of hyperprolactinaemia

Answer 4

1. Physiologic hyperprolactinaemia - occurs during pregnancy and lactation, return to normal afterwards
2. Prolactinoma
   (pituitary ademo) - benign tumor of lactotroph cells cause excess prolactin release
3. Hypothyroidism -
   • Increase in thyroid hormone by increases thyrotropin releasing hormone
   • Higher levels of prolactin induces
   • Medication - (1)Dopamine antagonists
   - will oppose dopamine thus remove inhibition on lactotrophs leading to elevated prolactin levels
   (2) Oestrogens -
   stimulate lactotrophs to produce prolactin directly
4. Damage to hypothalmamic-pituitary stalk
   - result of trauma, nearby tumors, brain surgery

Question 5

Symptoms

Answer 5

1. Women
   • Galactorrhea - increase in milk production
2. Men
   • Gynecomastia - breast enlargement
   •Erectile dysfunction -
3. Prolactinoma - presses on optic nerve causing headaches and impaired vision

Question 6

Diagnosis

Answer 6

1. Detecting high levels of prolactin in the blood

2. Brain MRI - prolactinomas

Question 7

Treatment

Answer 7

Varies based

1. Dopamine agonist
2. Prolactinoma - surgery
3. Hypothyroidism - Replacement thyroid hormones