Thyroxine (T4)

Thyroxine is a hormone synthesized and secreted by thyroid follicular cells, released into the blood circulation in a free form, and rapidly combined with plasma proteins. Basic Information Specialist classification: growth and development check classification: endocrine examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: 1 hypothyroidism: chronic thyroiditis, cretinism, iodine organic disorders, pituitary hypothyroidism. 2 normal thyroid function: TBG (thyroxine globulin) reduction (familial), nephrotic syndrome, artificial dialysis treatment, hypoproteinemia, protein loss gastrointestinal disease, cirrhosis, drugs (testosterone, protein differentiation hormone , adrenal glucocorticoids, salicylic acid, phenytoin, lenidine, heparin). 3 low T3 syndrome (severe), thyroid poisoning, taking T3 excess. Normal value: T4 (adult): 65-155mol/L T4 (child): 129-270mol/L Above normal: 1 thyroid poisoning: painless thyroiditis, subacute thyroiditis, exophthalmia hyperthyroidism, thyroid preparations, teratoma, malignant chorionic epithelioma, pituitary thyroid stimulating hormone tumor. 2 normal thyroid function: TBG (thyroid-binding globulin) increase (familial), pregnancy, newborn, part of liver cancer, hepatitis (acute phase), acute intermittent porphyria, drugs (steroids, birth control pills), anti- Thyroid hormone antibody-positive chronic thyroiditis, familial abnormal albuminemia, T4 pre-albumin (TBPA) hyperactivity, transient hyper-T4emia (acute disease, oral gallbladder contrast agent). negative: Positive: Tips: You must stop eating foods rich in iodine, such as kelp, seaweed, sea fish and shrimp, etc., depending on the amount of food, stop eating for 2-4 weeks. Normal value Thyroxine (T4) is 65-155 nmol/L in adults and 129-270 nmol/L in children. Clinical significance Abnormal result (1) rise 1 thyroid poisoning painless thyroiditis, subacute thyroiditis, exophthalmia hyperthyroidism, thyroid preparations, teratoma, malignant chorionic epithelioma, pituitary thyroid stimulating hormone tumor. 2 normal thyroid function TBG (thyroid-binding globulin) increase (familial), pregnancy, neonatal, part of liver cancer, hepatitis (acute phase), acute intermittent porphyria, drugs (steroids, birth control pills), anti-thyroid Chronic thyroiditis positive for positive antibody, familial abnormal albuminemia, pre-existing albumin (TBPA), transient hypertonic T4 (acute disease, oral gallbladder contrast agent). (2) lower 1 hypothyroidism chronic thyroiditis, cretinism, iodine organic disorders, pituitary hypothyroidism. 2 normal thyroid function TBG (thyroxine globulin) reduction (familial), nephrotic syndrome, artificial dialysis treatment, hypoproteinemia, protein loss gastrointestinal disease, cirrhosis, drugs (testosterone, protein differentiation hormone, Adrenal glucocorticoids, salicylic acid, phenytoin, lenidine, heparin). 3 low T3 syndrome (severe), thyroid poisoning, taking T3 excess. (3) T4 hyperthyroidism (T4 increased and T3 normal). The people who need to be tested have more sweat, chills, eye protrusions, more food and weight loss, fatigue and others. Low results may be diseases: painless thyroiditis, thyroid cyst, thyroid function normal goiter, subacute thyroiditis, nephrotic syndrome results may be high disease: resting lymphocytic thyroiditis, chronic lymphocytic thyroid Inflammation, endocrine disease, endemic cretinism, calcium pyrophosphate crystal deposition, teratoma considerations Before inspection: 1, must stop eating foods rich in iodine, such as kelp, seaweed, sea fish and shrimp, etc., depending on the amount of food, stop eating for 2 to 4 weeks. 2. The following drugs should be stopped before the examination. According to the dosage and time, stop taking 2~8 weeks. (1), iodine-containing drugs, such as iodide, compound iodine solution, iodine-containing tablets, etc. (2) Drugs that affect thyroid function, such as thyroid tablets and antithyroid drugs. (3) Some Chinese herbal medicines, such as seaweed, kelp, fritillary, burdock, Mutong, etc. Inspection process A common method for determining serum thyroid hormone is radioimmunoassay (RIA). This method combines the sensitivity of radiation with the specificity of the immune response and is a reliable, economical and specific assay. It is not affected by the amount of iodine contained in food; it is harmless to the human body after blood collection, and can be applied to pregnant women, lactating women, newborns and endangered patients; this method takes small blood volume and can be measured in other fields. It can also be repeatedly measured and widely used in clinical practice. Not suitable for the crowd People with reduced hematopoietic function such as leukemia, various anemia, myelodysplastic syndrome, or people with thrombocytopenia should pay attention to blood draw, and should not take more or more blood. Adverse reactions and risks 1. After the blood is drawn, do not press the needle hole to avoid subcutaneous hematoma. If there is a small piece of bruise in the blood, it is slightly tender, please don't panic, you can do hot compress after 24 hours to promote the absorption of blood. The general small amount of congestion will gradually absorb in 3 to 5 days and the color will become lighter and return to normal. 2. After the blood draw, symptoms such as dizziness, vertigo, fatigue, etc. should be immediately supine, drink a small amount of syrup, and then undergo a physical examination after the symptoms are relieved.