Thyroid Peroxidase (TPO) Antibody

Casandra

Casandra Test Code AR61614Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 0050075CPT Code 86376

Thyroid Peroxidase (TPO) Antibody

Also known as: AMICR

Clinical Use

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Use

The Thyroid Peroxidase (TPO) Antibody test is used to distinguish between autoimmune and non-autoimmune thyroid disorders, such as hypothyroidism, by measuring antibodies against thyroid peroxidase in the blood. Autoimmune thyroid disorders are often associated with an increased risk of developing other autoimmune diseases, thus timely and accurate diagnosis is crucial for the management of these conditions. It is commonly used to aid in diagnosing Hashimoto's thyroiditis and other forms of autoimmune thyroiditis, especially in pregnant women, as thyroid function can significantly impact pregnancy outcomes.

Special Instructions

Not recommended for initial testing of thyroid disorders. It is important to use this test to differentiate between autoimmune thyroid conditions like Hashimoto's thyroiditis and other forms of thyroid disorders. Proper interpretation of results in the context of clinical findings is essential for a correct diagnosis.

Limitations

The test should not be used as the initial screening for thyroid dysfunction. False negatives can occur, especially in the early stages of disease or after treatment has begun. Additionally, false positives may be found in the setting of other autoimmune conditions. Interfering substances in the blood sample, such as lipemia or hemolysis, can affect the accuracy of the test results.

Test Details

FDA Approved

New York Approved

Methodology

Immunoassay (CLIA)

Biomarkers

Thyroid Peroxidase (TPO) Antibody

Analyte

Concentration / Level • Quantitative (Continuous) (e.g., copies/mL, % expression)

LOINC Codes

Result Codes

8099-4

Result Turnaround Time

1 day

Specimen

Serum

Volume

0.5 mL

Minimum Volume

0.3 mL

Container

ARUP standard transport tube

Collection Instructions

Transfer 0.5 mL serum or plasma to an ARUP standard transport tube. Also acceptable: Lavender (EDTA), pink (K2EDTA), or green (sodium or lithium heparin).