The Anti-Thyroid Peroxidase assay

Written by: Solaris Diagnostics

The Anti-Thyroid Peroxidase assay is an in vitro test used for the quantitative determination of autoantibodies against thyroid peroxidase in human serum and plasma. The enzyme thyroid peroxidase (TPO) is integral to normal thyroid function as it allows for thyroid hormone synthesis. However, anti-thyroid peroxidase antibodies (aTPO) may be produced by the immune system in cases of autoimmune disease. Anti-thyroid peroxidase antibodies disrupt TPO function and therefore thyroid hormone synthesis, resulting in abnormal thyroid function.

Elevated aTPO levels can assist in the diagnosis of thyroid disorders, particularly autoimmune diseases like Hashimoto’s disease, the most common cause of thyroiditis. Hashimoto’s Disease results in hypothyroidism, when the thyroid does not produce enough thyroid hormone, and 90% of patients present with aTPO antibodies. Given that the thyroid plays a major role in the metabolism, growth, and development of the human body, an underactive thyroid can cause a wide variety of symptoms including but not limited to fatigue, joint pain, cold sensitivity, and irregular menstrual periods.

An aTPO antibody test would typically be used in conjunction with other tests that measure thyroid function like TSH, thyroid stimulating hormone, and FT4, free thyroxine, as well as other autoantibody tests like anti-thyroglobulin antibody which when elevated may also serve as an indicator of Hashimoto’s disease. Elevated aTPO levels may also assist in the diagnosis of Graves’ disease, another autoimmune disease which results in hyperthyroidism, the overproduction of thyroid hormones. Hyperthyroidism also has a wide range of symptoms including but not limited to fatigue, heat intolerance, hyperactivity, and irregular heartbeat. Autoimmune thyroid disease is found in about 5% of the population, though thyroid antibodies are seen in 10-20%.

At Solaris Diagnostics, aTPO is measured with a competitive immunoassay using chemiluminescent technology on an Atellica IM Analyzer. The test method requires assay-specific reagent, acid, and base in order to generate a chemiluminescent reaction. During analysis, a luminometer measures the light emitted from the reaction as Relative Light Units (RLUs) and software converts the RLUs to results. Solaris Diagnostics can provide aTPO results within 24 hours from the time the sample is received in the laboratory.

#AntiThyroidPeroxidaseAntibody #aTPO #ThyroidFunction #AutoimmuneDisease #HashimotosDisease #Thyroiditis #Hypothyroidism #ThyroidDisorders #GravesDisease #Hyperthyroidism #ThyroidAntibodies #ThyroidHealth #ThyroidTest #AutoantibodyTest #ThyroidFunctionTest #ThyroidHormones #ChemiluminescentTechnology #SolarisDiagnostics

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