|Category||Biochemistry >> Endocrinology|
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. Macroprolactin investigations use a PEG precipitation procedure to remove macroprolactin so that the remaining bioactive monomeric form of prolactin can be estimated.
Differential diagnosis of macroprolactin-associated hyperprolactinaemia with that of prolactinoma, hypothyroidism or drug/stress-induced hyperprolactinaemia. For samples assayed for total prolactin within NWLP laboratories macroprolactin investigations are automatically added for male patients with total prolactin >450 mU/L and female >600 mU/L.
Monomeric prolactin reference range:
Male <310 mU/L
Female <420 mU/L
|Sample & container required||SST (gold top) or serum (red top)|
|Sample volume||0.5 mL|
|Transport storage||Stable for 7 days at 2-8°C. Samples can be sent by first class post.|
|Turnaround time||10 days|