TSH (Thyroid Stimulating Hormone) Test
1,700 Kshs | Home Collection Available
Synonyms
Third-generation THS, thyrotropin
Purpose
The TSH (Thyroid Stimulating Hormone) Test is a blood test that measures the level of TSH in your bloodstream. The pituitary gland produces TSH, a hormone that regulates the thyroid gland’s production of thyroid hormones (T3 and T4).
This test is essential for evaluating thyroid function. Abnormal TSH levels can help diagnose hypothyroidism (underactive thyroid), hyperthyroidism (overactive thyroid), thyroid disorders in newborns, and monitor thyroid hormone replacement therapy.
Detecting thyroid imbalances early can prevent complications such as weight changes, fatigue, depression, infertility, or heart issues. To get a complete picture of thyroid health, the TSH test is often combined with Free T3 (FT3), Free T4 (FT4), thyroid antibodies, Thyroglobulin, ultrasound, or thyroid scans.
Patient Preparation
The patient should avoid taking biotin supplements at least 72 to sample collection.
Samples
1ml with a minimum volume of 0.7ml of serum collected in a Gel-barrier, red-top, or green-top tube (lithium heparin). Avoid using EDTA, oxalate, or citrate plasma. Transfer the separated serum to a plastic transport tube if a red-top tube is used. Store the sample at room temperature.
Reference Range
>10 years;0.450-4.500uIU/mL
Results Turnaround
Within 24 hours of receipt of samples.
Diseases / Diagnostic indicators
The TSH test helps identify whether the thyroid gland is underactive, overactive, or functioning normally by measuring how much thyroid-stimulating hormone is in the blood.
- High TSH levels
May indicate hypothyroidism, a condition where the thyroid does not produce enough hormones. Common causes include Hashimoto’s thyroiditis or iodine deficiency. Some old people, individuals, or patients with pituitary adenomas that secrete excess TSH may also show high TSH levels.
- Low TSH levels
Suggest hyperthyroidism, where the thyroid gland produces too much hormone. This may be due to conditions like Graves’ disease or thyroid nodules.
- Normal TSH levels
Typically indicates a healthy, well-functioning thyroid. However, further testing may still be needed if symptoms persist.
- Abnormal TSH with normal T3 and T4
Could suggest subclinical thyroid disease, requiring careful monitoring over time. For more on TSH testing, read this study.