Hyperprolacteniemia
•
HP is the commonest cause of amenorrhea ( pituitary cause ) .
•
Prolactin is a hormone secreted from lactotrophes cells of anterior pituitary
gland , its function is for synthesis and production of milk from the glandular
tissue of the breast.
•
It is inhibited by dopamine & dopamine agonist which act on hypothalamus.
•
The normal level of prolactin is < 400 mu/L
•
Causes of hyperprolactinemia:
Physiological :
1- Pregnancy
2- Lactation
3- Breast examination
4- Venipuncture
5- Sleep
6- Stress
Pathological :
1- Idiopathic
2- Pituitary adenoma ( microadenoma < 10 mm , macroadenoma > 10
mm which serum level reach > 8000 mu/L)
3- Non-functional pituitary or hypothalamic tumor in which serum
prolactin my reach > 3000 mu/L
4- Renal failure
5- Hypothyroidism
6- PCOS
7- Drugs like :
a. Metoclopramide
b. Phenothiazine
c. Omeprazole
d. Methyldopa
e. Reserpine
د.ﺳﮭﺎ
-
ﻧﺳﺎﺋﯾﺔ
۱
Clinical Features:
The patient presented with different signs & symptoms :
- Less than 50 % has galactorrhea ( milk or breast discharge ) .
- Headache
- Visual disturbance due to pressure or compression of optic chiasma
- Sign of hypoestrogenemia as prolactin inhibit the release of estrogen , other
sign include oligomenorrhea , amenorrhea , primary or secondary infertility ,
while patient with PCOS may have hyperprolactinemia with normal estrogen &
withdrawal bleeding when giving progesterone ..
Investigations :
1- Serum prolactin
2- Serum progesterone to confirm ovulation if > 30 nmol/L .
3- Skull x-ray .
4- CT of MRI for pituitary gland if serum prolactin after 2 measures is > 1000
mu/L.
Serum prolactin level may vary as in :
- PCOS > 2500 mu/L.
- Microadenoma 1500-4000 mu/L .
- Macroadenoma > 8000 mu/L.
- Non-functional tumors > 3000 mu/L.
On skull x-ray , if tumor size > 10 mm, show enlargement of pituitary fossa,
erosion of clinoid process.
CT scan may show compression of optic chiasma .
Management:
1- Medical treatment :
A- Stop certain drugs that may cause hyperprolactinemia if the patient use it .
B- If sometime the patient on phenothiazine ( which is used for treatment of
schizophrenia ) , so it reasonable to continue on it & use low dose oral
contraceptive pill to prevent hypoestrogenemia
۲
1) Bromocriptine:
Which is dopamine agonist & most patient show decrease in serum
prolactin after few days & decrease in tumor size after or within 6 weeks.
- Side effects: nausea , vomiting , headache , postural hypotension, so this
drug taken at night , low dose in the first 3 days, in the middle of mouth
full of food.
- Long term Side effects:
Raynaud , constipation.
- Dose : 1/2 tablet at night (1.25 mg) , increase gradually + 2.5 mg at night
+ 1.25 mg at day until daily dose reach 7.5 mg /day ( 2.5 mg × 3 )
2) Cabergoline: once or twice / week ( mg /day) , it is dopamine agonist also ;
but long acting and less side effect
2-
Surgical treatment : trans sphenoidal adenomectomy in case of :
1. Failure of medical treatment.
2. Patient develop side effects of drugs.
3. Large macroadenoma.
4. Suprasellar extension.
5. When pregnancy is desired.
- So with good skill of surgery , there is no widely role of radiation which lead
to hypopituitarism.
- If the patient with microadenoma on treatment and become pregnant , so
stop Bromocriptine as there is less chance of the tumor to expand (rarely in
about 2% ).
- While in case of macroadenoma , the chance of re-expansion is 25% , so the
patient should advice to continue on treatment .
- Also in case of Suprasellar extension, it is reasonable to use Bromocriptine in
pregnancy + visual field assessment .
- Follow up the patient by serum prolactin and MRI for tumor size.
- If the patient has high serum prolactin but regular menstrual cycle, no
treatment is required unless there is unovulatory cycle & fertility is desired.
۳