When examined by immunofluorescence staining, anti-thyroid microsomal antibodies (ATM) can cause cytoplasmic and apical portion fluorescein on the thyroid cytoplasm. This autoantibody was discovered by Belyavin et al. in 1959 using sucrose density gradient differential centrifugation to extract antigen from thyroid tissue and reacting with sera from patients with Hashimoto's thyroiditis. The target antigen of ATM is thyroid peroxidase (TPO), which is a membrane-bound hemoprotein located on the surface (top) of thyroid cells, exocytosis and endogenous vesicles (exo/endocytoticvesicles). The main function is to catalyze the iodination of thyroglobulin and its coupling with tyrosine to produce T3 and T4. TPO has a molecular weight of 105 kD and consists of 933 amino acids, of which 842 are extracellular, 29 are transmembrane, and 62 are intracellular. The TPO cDNA is 42% homologous to myeloperxidase, which may be responsible for the production of anti-neutrophil cytoplasmic antibodies in some patients with autoimmune thyroid disease. The IgG subclass distribution of ATM is similar to that of ATG. ATM binds to complement and inhibits TPO activity, which has been shown to be cytotoxic to thyroid cells in vitro.

Basic Information

Specialist classification: growth and development check classification: immunological examination

Applicable gender: whether men and women apply fasting: fasting

Analysis results:

Below normal:

Normal value:
no

Above normal:

negative:
normal.

Positive:
Tips may have Hashimoto's thyroiditis.

Tips: After 8 pm on the day before the medical examination, you should start fasting for 12 hours. Normal value

Normal person ATM is negative.

Clinical significance

In patients with Hashimoto's thyroiditis, the positive rate of ATM can reach 95%; the positive rate of ATM in patients with hyperthyroidism and primary mucinous edema is 85%-95%; the positive rate of ATM in subacute thyroiditis and thyroid cancer patients is about 15%. Because of the possible cross-reactivity of TPO with myeloperoxidase, ATM may also be positive in patients with peri-nuclear anti-neutrophil cytoplasmic antibodies.

Precautions

First, the precautions before blood draw:

1, do not eat too greasy, high-protein food the day before the blood, to avoid heavy drinking. The alcohol content in the blood directly affects the test results.

2. After 8 pm on the day before the medical examination, you should start fasting for 12 hours to avoid affecting the test results.

3, should relax when taking blood, to avoid the contraction of blood vessels caused by fear, increase the difficulty of blood collection.

Second, after blood draw should pay attention to:

1. After blood is drawn, local compression is required at the pinhole for 3-5 minutes to stop bleeding. Note: Do not rub, so as not to cause subcutaneous hematoma.

2, the pressing time should be sufficient. There is a difference in clotting time for each person, and some people need a little longer to clotting. Therefore, when the surface of the skin appears to be bleeding, the compression is stopped immediately, and the blood may be infiltrated into the skin due to incomplete hemostasis. Therefore, the compression time is longer to completely stop bleeding. If there is a tendency to bleed, the compression time should be extended.

3, after the blood draw symptoms of fainting such as: dizziness, vertigo, fatigue, etc. should immediately lie down, drink a small amount of syrup, and then undergo a physical examination after the symptoms are relieved.

4. If there is localized congestion, use a warm towel after 24 hours to promote absorption.

3. Please inform the doctor about the recent medication and special physiological changes before the test.

Inspection process

Same as ELISA.

Not suitable for the crowd

There are no taboos.

Adverse reactions and risks

There are no related complications and hazards.