Thyroid Stimulating Hormone (TSH)

Message

Test performed at York Hospital Laboratory.

Test Code

TSH

Alias/See Also

TSH

CPT Codes
84443

Preferred Specimen

0.3 mL Serum

Transport Container

Serum Separator Tube
Green Top Lithium Heparin Tube also acceptable

Transport Temperature

Refrigerated

Specimen Stability

Room temperature: 4 hours
Refrigerated: 7 days
Frozen: 4 weeks

Methodology
Chemiluminescence

Setup Schedule

Daily

Report Available

Next Day
Available STAT 1 1/2 Hour

Reference Range

Age	TSH (uU/mL)
<=4 Days	1.0-39.0
1-4 Weeks	1.7 - 9.1
1-12 Months	0.8 - 8.2
1-20 Years	0.7 - 5.7
Adult	0.5 - 4.7

Clinical Significance

The diagnosis of overt hypothyroidism by the finding of a low total T4 or free T4 concentration is readily confirmed by a raised TSH concentration. Measurement of low or undetectable TSH concentrations may assist the diagnosis of hyperthyroidism, where concentrations of T4 and T3 are elvated and TSH secretion is suppressed. TSH tests with high levels of precision and functional sensitivity claims of 0.01-0.02 mIU/L have been termed "third generation" tests. These have the advantage of discriminating between the concentrations of TSH observed in thyrotoxicosis, compared with the low, but detectable, concentrations that occur in subclinical hyperthyroidism.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.