Pathology Handbook

Thyroid antibodies

Synonyms

TPO
Thyroid Peroxidase Antibodies

Clinical Indications

Hashimoto's Thyroiditis
Primary Myxoedema
Grave's Disease (often associated with exophthalmia)
Other sub acute thyroiditis syndromes (e.g. post partum thyroiditis)
Please note: These antibodies are found at high levels in up to 90% of patients with autoimmune diseases, however, low antibody levels may also be found in patients with thyroid carcinoma and occasionally in healthy individuals. In addition they may be found in patients with other organ-specific autoimmune diseases such as Pernicious Anaemia and Addison's disease

Test Includes

Detection of IgG autoantibodies against Thyroid Peroxidase Antigen

Request Form 

Request via ICE

Availability

Assay is performed daily.

Specific Criteria

It is essential to give relevant clinical information

Turnaround Time

Results are available within 3 days.

Specimen

Serum

Volume

7 ml

Container

Vacutainer red top

Collection

Samples should be transported to the laboratory immediately

Lab Handling

Aliquot and store at 4-8°C prior to testing and at -20°C or below for up to 1 month after receipt.

Causes for Rejection

Unlabelled/inadequately labelled sample
Inadequately completed request form
Delay in sample reaching laboratory

Reference Range

0-34IU/mL

Levels above 34IU/mL are regarded as POSITIVE