Laboratory: Clinical Biochemistry
Test Name:
Test Code: TPO
Clinical Information:
Test Indications: This test is used to assist in the diagnosis of thyroid autoimmune disorders and to differentiate autoimmunity from nonautoimmune goitre or hypothyroidism. High anti-TPO titres are found in up to 90% of patients with chronic Hashimoto's thyroiditis. In Graves disease, 70% of the patients have an elevated titre.
Patient Preparation Instructions: Multivitamins (45–125 µg biotin) or biotin-only supplements up to 1 mg per day do not interfere with this test. Samples should not be taken from patients receiving therapy with high biotin doses (i.e. >5 mg/day) until at least 8 hours after the last dose.
Collection Devices:
Specimen Required:

Plasma: 2.0 mL
Pediatric Plasma: 0.2 mL

Stability 8 days refrigerated, 6 months frozen
Serum: 2.0 mL

Samples must be transferred to an aliquot tube and stored frozen if analysis will not be complete within 48 hours (#110-10-05 Serum / Plasma Separation Procedure & Transport)
Reference Values:
< 34 IU/mL
(HSC): Specific Days - Monday, Wednesday and Friday. <br/>(SBH): Weekdays - Monday-Friday for St. Boniface only.
See Also:
More Information: