Hyperprolactinaemia Flashcards Preview

Lecture Notes - Endocrinology > Hyperprolactinaemia > Flashcards

Flashcards in Hyperprolactinaemia Deck (21)
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1
Q

What is hyperprolactinaemia

A

The presence of abnormally high circulating prolactin levels secreted by the lactotroph cells in the anterior pituitary

2
Q

What up regulates prolactin gene expression and synthesis

A

oestrogen

3
Q

Describe the prolactin levels in premenopausal women compared to men

A

Higher

4
Q

What inhibits prolactin secretion

A

dopamine

5
Q

What can cause hyperprolactinaemia

A

reduced dopamine secretion
reduced dopamine delivery to the anterior pituitary via the portal vessels
dopamine antagonists

6
Q

When are prolactin levels also high

A

After exercise, meals and sex
during physical or psychological stress
following an epileptic fit
Polycystic ovary syndrome

7
Q

What are more common, micro or macro prolactinomas

A

Micro

8
Q

What are the two main clinical presentations of hyperprolactinaemia

A

Galactorrhoea and symptoms of hypogonadism
menstrual irregularities or delayed menarche in women
reduced libido, impotence or infertility in men

9
Q

What might longstanding hyperprolactinaemia result in

A

low bone mineral density and osteoporosis

10
Q

When does the hook effect occur

A

When the assay uses antibodies that recognise two ends of the molecule
Very high prolactin levels may be reported as normal or modestly elevated

11
Q

How can the hook effect be avoided

A

repeating the assay using a 1:100 dilution of serum

12
Q

Patients with macro adenomas should have what tests carried out to look for hypopituitarism

A

Visual field testing

Pituitary function tests

13
Q

What are some indications for treatment of hyperprolactiaemia

A

existing or impending neurological symptoms due to local compression by a macroprolactinoma
a desire for fertility
the presence of symptoms : menstrual problems or loss of libido
Bone density maintenance

14
Q

What do dopamin agonists do

A

reduce prolactin secretion and the size of prolactinomas

15
Q

What is the first line treatment for prolactinomas

A

Dopamine (D2) receptor agonists (cabergoline or bromocriptine) regardless of the size of the adenoma and the severity of the neurological sequelae

16
Q

Why is cabergoline preferred to bromocriptine

A

Better tolerated (fewer and milder side effects)
more effective in reducing prolactin levels
more effective in restoring ovulatory cycles

17
Q

What is the starting dose of cabergoline in adults

A

250ug twice weekly

18
Q

What is often associated with a spontaneous resolution of prolactinomas in women

A

the menopause

19
Q

are patients usually on life long cabergoline treatment

A

Sometimes - if the prolactin levels and pituitary size have been normal for 2 or more years, a trial of withdrawal should be attempted

20
Q

What drug is first line for a woman who wishes to conceive but has hyperprolactinaemia

A

Bromocriptine - there is more evidence that it has no teratogenic effects

21
Q

What is the main investigation for hyperprolactinaemia

A

Pituitary MRI once physiological causes have been excluded