USC
ENDOCRINE LABORATORIES
TEST INDEX
THYROID
STIMULATING HORMONE (TSH)
Methodology
Electrochemiluminescence Immunoassay
Performed
Tue, Fri
Reported
Same day
Collect
One 6mL
RT (Min: 4mL RT)
Transport
2 mL
refrigerated serum
(Min: 0.8 mL)
Stability
Stored at
2 - 8°C until
used; Stable if frozen at - 20°C
Unacceptable
Do
not
use
heat-inactivated samples.
Reference
Range 0.30
– 4.00 mIU/L
CPT
Code 84443
Information:
The determination
of TSH serves as the initial test in
thyroid diagnostic evaluation of ambulatory patients. Even very slight
changes in the concentrations of the free thyroid hormones bring about
much greater opposite changes in the TSH level. Accordingly, TSH is a
very sensitive and specific parameter for assessing thyroid function
and is particularly suitable for early detection or exclusion of
disorders in the central regulating circuit between the hypothalamus,
pituitary and thyroid.
Thyroid-stimulating hormone (TSH, thyrotropin) is a glycoprotein having
a molecular weight of approximately 30,000 daltons and consisting of
two subunits. The beta-subunit carries the TSH-specific immunological
and biological information, whereas the alpha-chain carries
species-specific information and has an identical amino acid sequence
to the alpha chains of LH, FSH and hCG.
TSH is formed in specific basophil cells of the anterior pituitary and
is subject to a circadian secretion sequence. The hypophyseal release
of TSH (thyrotropic hormone) is the central regulating mechanism for
the biological action of thyroid hormones. TSH has a stimulating action
in all stages of thyroid hormone formation and secretion; it also has a
proliferative effect.
Home |
General
Information
| Billing
| Contact Us