Thyroid Peroxidase Antibodies (Anti-TPO)
Antithyroid Microsomal Antibody
Differential diagnosis of hypothyroidism and thyroiditis
Antibodies to thyroid microsomes (thyroid peroxidase) are present in 70% to 90% of patients with chronic thyroiditis. They are also present in smaller percentages of patients of other thyroid diseases. Antibody production may be confined to lymphocytes within the thyroid, and serum may be negative. Small numbers (3%) of people with no evidence of disease may have antibody. This is more frequent in females and increases with age.
0.3 mL (Note: This volume does not allow for repeat testing.)
Red-top tube or gel-barrier tube
If red-top tube is used, transfer separated serum to a plastic transport tube.
Room temperature 14 days
Refrigerated 14 days
Frozen 14 days
Citrate plasma specimen; improper labeling