PrintView

Reference Notes and Guidelines

1. One of the known interferences causing markedly increased serum levels of prolactin is increased serum concentration of biologically inactive macroprolactin. Hence, all sera with increase total prolactin are routinely tested for the presence of macroprolactin using PEG precipitation.

2. If total prolactin is elevated. Post-PEG Prolactin will be performed and the corrected result reported under a Post-PEG Prolactin result. The Post-PEG Prolactin result should be used for interpretation.

3. Increased results may be seen in multiple medications, including patients on high doses of biotin (i.e. > 5mg/day - collect 8 hours after last dose), estrogens, antidepressants, antihypertensive and other drugs. Other conditions include autoimmune diseases, hypothyroidism, pregnancy, postpartum lactation, stress, exercise. Therefore test results alone cannot be interpreted as absolute evidence for the presence or absence of malignant disease.

4. Sample is best collected 3-4 hours after waking.

Source: Roche cobas Prolactin package insert: ref. 03203093 (2017-10), V7.0