-Graves disease = the most common cause of hyperthyroidism in the United States.
-Graves’ disease (thyrotoxicosis) is an autoimmune disorder in which a unique antibody called thyroid-stimulating antibody (also called TSH Receptor Antibodies) stimulates the TSH receptors causing thyroid cells to grow larger and to produce excessive amounts of thyroid hormones (T4 & T3). In Grave’s disease, the goiter is due not to TSH but to this unique antibody.
-Risk factors for Graves disease include female sex and personal or family history of an autoimmune disorder.
“Unlike radioactive iodine, methimazole has been shown to decrease the risk of development or progression of ophthalmopathy in Graves disease.”ABFM Critique
—///—
thyrotropin = TSH
Diagnosis Notes
Anti-thyroid antibodies attack and destroy the thyroid gland leading to hypothyroidism. Two types are anti-TPO and antithyroglobulin. Hashimoto’s is the most common type.
TSH Receptor Antibodies (also called thyroid Stimulating Antibodies) hyperstimulate the thyroid gland leading to hyperthyroidism (as seen in Graves disease, the most common cause of hyperthyroidism).
Distinguishing Graves from other causes of Hyperthyroidism
In a postpartum female, the following can cause hyperthyroidism as evidenced by low TSH and elevated T4 and T3. However, only Graves can cause a high radioactive iodine uptake (RAIU) on a thyroid scan.
- Postpartum thyroiditis
- Silent thyroiditis
- Subacute thyroiditis
- Graves disease
- Exogenous thyroid ingestion
Reference / Further Reading
JAMA. 2015;314(23):2544–2554. Management of Graves Disease: A Review. https://www.ncbi.nlm.nih.gov/pubmed/26670972
Am Fam Physician. 2016 Mar 1;93(5):363-370. Hyperthyroidism: Diagnosis and Treatment. http://www.aafp.org/afp/2016/0301/p363.html