Skip to main content

Login to North West London Pathology – consumables service

If you need a new account or you have a query about your order, please telephone the pathology call centre on 0203 313 5353.

If you have forgotten your password you can reset this yourself. Please click here if you have forgotten your password.

Results Line and Enquiries

0203 313 5353


Category Biochemistry >> Endocrinology
Test background

Macroprolactinaemia refers to a polymeric form of prolactin in which several molecules form aggregates with circulating IgG. This rarely elicits a biological response due to the inability of such a large molecule to interact with the prolactin receptor, however, it can be detected by immunoassays leading to spurious elevated prolactin results.

Clinical Indications

Differential diagnosis of macroprolactin-associated hyperprolactinaemia with that of prolactinoma, hypothyroidism or drug/stress-induced hyperprolactinaemia, eg. Assayed prolactin >600 mIU/L (female) or >350mIU/L (male) where physiological or pathological causes of hyperprolactinaemia are excluded

Reference range

See report

Sample & container required SST (gold top) or serum (red top)
Sample volume 0.5 mL
Transport storage Stable at 2-8°C for 72 hours. Please freeze pending dispatch for analysis. Sample can be sent by first class post.
Turnaround time 10 days