IVD of Thyroid
What is the Thyroid?
The thyroid is a butterfly-shaped endocrine gland located near the base of the neck, just below the Adam's apple. It is essential for many metabolism processes within the body.
Functions of the Thyroid
The primary function of the thyroid is to produce hormones that regulate the body's metabolism, which is the conversion of food into energy.
Metabolism Regulation: The thyroid gland releases hormones such as thyroxine (T4) and triiodothyronine (T3), which regulate the body's metabolism. These hormones dictate how fast or slow the cells in your body work.
Heart and Muscle Function: Thyroid hormones impact heart rate and strength, as well as muscle control.
Brain Development: They play a significant role in brain development, particularly during infancy and childhood.
Bone Maintenance: These hormones are essential for bone development and bone density.
Temperature Regulation: The thyroid helps regulate body temperature by controlling the speed of metabolism.
What is Thyroid Disease?
Thyroid disease includes disorders affecting the thyroid gland. These conditions disrupt thyroid hormone production, which causes a broad range of symptoms. Hypothyroidism, hyperthyroidism, thyroiditis, and thyroid cancer are the most frequent thyroid diseases.
Causes of Thyroid Disease
Autoimmune Disorders: With conditions like Hashimoto's thyroiditis and Graves' disease, the immune system attacks the thyroid gland.
Iodine Deficiency: Iodine is critical for thyroid hormone production, and its deficiency can lead to goiter and hypothyroidism.
Genetic Factors: Family history can increase the risk of thyroid disorders.
Radiation Exposure: Exposure to radiation, particularly in the neck area, can cause thyroid problems.
Thyroid Surgery or Illness: Surgical removal or some thyroid illnesses can cause hypothyroidism.
Symptoms of Thyroid Disease
Hypothyroidism (Underactive Thyroid)
- Fatigue
- Weight gain
- Cold intolerance
- Dry skin and hair
- Depression
- Muscle weakness
- Slowed heart rate
Hyperthyroidism (Overactive Thyroid)
- Weight loss
- Rapid heartbeat
- Increased appetite
- Nervousness or anxiety
- Tremors
- Heat intolerance
- Sweating
Treatment of Thyroid Diseases
Medication:
Hypothyroidism: Treated with synthetic thyroid hormone (levothyroxine) to replenish the deficient hormones.
Hyperthyroidism: Treated with anti-thyroid medications (e.g., methimazole) to reduce hormone production.
Radioactive Iodine Therapy: Used for hyperthyroidism and thyroid cancer, it destroys overactive thyroid cells.
Surgery: Total or partial thyroid gland removal may be needed in the presence of large goiter, cancer, or hyperthyroidism that is resistant to treatment.
Lifestyle and Dietary Changes: Taking adequate amounts of iodine is essential and patients might be given dietary recommendations to alleviate symptoms.
Beta-blockers: Developed to control symptoms such as fast heart rate in hyperthyroidism.
In-Vitro Diagnostic Methods for Thyroid Disease
Blood Tests: Measure levels of Thyroid Stimulating Hormone (TSH), T3, and T4. TSH is often the most sensitive marker for thyroid function.
Imaging Tests
Ultrasound: Allows visualization of the thyroid structure and identify nodules or tumors.
Radioactive Iodine Scans: Monitor thyroid structure and function through radioactive iodine uptake.
Biopsy: Fine-needle aspiration biopsy may be ordered if thyroid nodules are found to confirm whether they are cancerous.
Biomarkers for Thyroid Diseases
Thyroid Hormones:
Thyroid Stimulating Hormone (TSH): Produced by the pituitary gland, it regulates the production of thyroid hormones.
Thyroglobulin: Used to monitor thyroid cancer treatment and potential recurrence.
Antibodies:
Anti-thyroid peroxidase (anti-TPO): Common in Hashimoto's thyroiditis.
Thyroid-stimulating immunoglobulin (TSI): Often elevated in Graves' disease.
Calcitonin: High levels may indicate medullary thyroid cancer.
Case Study
Case 1: Sacristán-Gómez P, Serrano-Somavilla A, Castro-Espadas L, et al. Evaluation of Epithelial-Mesenchymal Transition Markers in Autoimmune Thyroid Diseases. Int J Mol Sci. 2023 Feb 8;24(4):3359. doi: 10.3390/ijms24043359. PMID: 36834770; PMCID: PMC9965822.
The authors established an in vitro TGF-β-stimulation assay in a human thyroid cell line to assess EMT and PC disruption. EMT markers were evaluated in this model using RT-qPCR and WB, and PC was evaluated with a time-course immunofluorescence assay. They found an increased expression of the mesenchymal markers α-SMA and fibronectin in TFCs in the thyroid glands of AITD patients.
Fig2. RNA expression of EMT-associated markers in thyroid tissue from controls, HT, and GD patients. Significant correlation analysis of the genes analyzed by RT-qPCR with different clinical laboratory parameters. Abbreviations—ns: not significant, TSH: thyroid-stimulating hormone; FT4: free-T4 hormone; TSH-R-Ab: TSH receptor antibody.Case 2: Klasson CL, Sadhir S, Pontzer H. Daily physical activity is negatively associated with thyroid hormone levels, inflammation, and immune system markers among men and women in the NHANES dataset. PLoS One. 2022 Jul 6;17(7):e0270221. doi: 10.1371/journal.pone.0270221. PMID: 35793317; PMCID: PMC9258892.
Researchers used the U.S. National Health and Nutrition Examination Survey (NHANES) to investigate the relationship between daily physical activity and both thyroid and immune activity. These results underscore the long-term impact of daily physical activity on both systemic metabolic activity (thyroid) and on specific physiological tasks (immune).
Fig3. Physical activity's relationship to thyroid hormones. The relationship between TSH and T4. The 1999–2002 data is represented by the top graph while 2007–2012 is on the bottom. Slopes for bivariate regressions of ln-transformed values shown separately for subjects reporting physical activity ("Active", red) or no physical activity ("Inactive", blue) in their leisure time (PAD200/PAQ650, solid line) or occupation (PAQ180/PAQ665, dashed line).