Hyperprolactinaemia Flashcards
What is hyperprolactinaemia
The presence of abnormally high circulating prolactin levels secreted by the lactotroph cells in the anterior pituitary
What up regulates prolactin gene expression and synthesis
oestrogen
Describe the prolactin levels in premenopausal women compared to men
Higher
What inhibits prolactin secretion
dopamine
What can cause hyperprolactinaemia
reduced dopamine secretion
reduced dopamine delivery to the anterior pituitary via the portal vessels
dopamine antagonists
When are prolactin levels also high
After exercise, meals and sex
during physical or psychological stress
following an epileptic fit
Polycystic ovary syndrome
What are more common, micro or macro prolactinomas
Micro
What are the two main clinical presentations of hyperprolactinaemia
Galactorrhoea and symptoms of hypogonadism
menstrual irregularities or delayed menarche in women
reduced libido, impotence or infertility in men
What might longstanding hyperprolactinaemia result in
low bone mineral density and osteoporosis
When does the hook effect occur
When the assay uses antibodies that recognise two ends of the molecule
Very high prolactin levels may be reported as normal or modestly elevated
How can the hook effect be avoided
repeating the assay using a 1:100 dilution of serum
Patients with macro adenomas should have what tests carried out to look for hypopituitarism
Visual field testing
Pituitary function tests
What are some indications for treatment of hyperprolactiaemia
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
What do dopamin agonists do
reduce prolactin secretion and the size of prolactinomas
What is the first line treatment for prolactinomas
Dopamine (D2) receptor agonists (cabergoline or bromocriptine) regardless of the size of the adenoma and the severity of the neurological sequelae
