Test BackgroundThe α-subunit is common to TSH, LH, FSH and hCG, while the β-subunit is specific to each hormone. The subunits are synthesised and secreted independently. The α-subunit is consistently elevated in cases of TSH secreting pituitary adenoma and its secretion is autonomous and refractory to the negative feedback of thyroid hormones.
Sample Required Serum (red top)
Sample Volume 0.5 mL
Turnaround Time Up to 6 weeks
NotesNot currently performed in house; this is a referred test