Hyperprolactinaemia

Question 1

What are the causes of hyperprolactinaemia?

Answer 1

• Prolactinoma
• Mixed growth-hormone-producing (somatotroph) and prolactin-producing (mammotroph) tumours
• Pituitary macroadenomas that causes stalk compression: the elevation of prolactin in this case will not be as high as that of prolactinoma
• Primary Hypothyroidism (causing excessive TSH secretion&raquo_space;> dopamine’s inhibitory effects)

Question 2

What are the clinical features of hyperprolactinaemia?

Answer 2

Galactorrhoea, spontaneous or expressible (60% of cases)

Oligomenorrhoea or amenorrhoea

Decreased libido in both sexes

Decreased potency (i.e. ED) in men

Subfertility

Symptoms or signs of oestrogen or androgen deficiency eg: Osteoporosis especially in women, in the long term

Delayed or arrested puberty in the peripubertal patient

Mild gynaecomastia is often seen in men due to the associated hypogonadism rather than a direct effect of prolactin.

Headaches and/or visual field defects occur if there is a pituitary tumour

• Headache = Due to irritation of meninges
• Visual Disturbances = due to compression on optic chias

Question 3

What are the investigations of hyperprolactinaemia?

Answer 3

Check Visual Fields
Primary Hypothyroidism must be excluded: a potentially reversible cause of hyperprolactinaemia

Anterior pituitary function 🡪 in case of pituitary tumor or hypopituitarism

MRI of the pituitary if there are evidence of pituitary tumor

Question 4

What is the management of hyperprolactinemia?

Answer 4

Dopamine Agonist

• Cabergoline: The first drug of choice. Best tolerated and longest-acting drug
• Bromocriptine: Preferred if pregnancy is planned
• Quinagolide
• Prolactinomas usually shrink in size on a dopamine agonist
• However, will recur if treatment is stopped.

Trans-sphenoidal surgery: Rarely completely successful with macroadenomas and risks damage to normal pituitary function.