Graves Disease
Graves' disease is the commonest cause in iodine-sufficient countries.
Graves' Disease
- Overview : An autoimmune disorder where antibodies (TSI) stimulate the thyroid gland, leading to excessive thyroid hormone production .
- Exophthalmos (bulging eyes).
- Increased metabolic rate : Weight loss, heat intolerance, and increased appetite.
- Antithyroid medications : Methimazole or PTU.
- Radioactive iodine therapy or surgery in severe cases.
Read this in LECTURE 4: Thyroid Hormones
What our notes say
- Graves' disease is the commonest cause in iodine-sufficient countries. (Internal Medicine 4th Year Endocrinology CAT: 30 MCQs)
- Graves' disease is also not a usual cause (it causes hyperthyroidism), but C is the clearest. (Internal Medicine 4th Year Endocrinology CAT: 30 MCQs)
- Eye signs and pretibial myxoedema are specific to Graves' disease. (Internal Medicine (MBIM 4100) main exam, Paper One: 3 July 2019)
- This is thyrotoxicosis (Graves disease): warm sweaty skin, tachycardia, tremor, increased appetite with weight loss, and exophthalmos. (Paediatrics end of fourth year special supplementary exam: August 2019, Paper On)
- Hyperthyroidism with a diffuse goitre and eye signs (exophthalmos) is Graves disease, caused by TSH receptor-stimulating antibodies. (Endocrinology and Gastroenterology Question Bank: 12 Clinical MCQs)
- There are both thyroid-stimulating immunoglobulins (TSI) and thyroid growth-stimulating immunoglobulins (TGI) in Graves disease. (Chemical pathology and Endocrine pathology — Past Paper Questions & Answers)
Study material on Graves Disease
- Chemical pathology and Endocrine pathology
- Chemical Pathology: Endocrine Cases, Pituitary & Thyroid Q&A
- Internal Medicine 4th Year Endocrinology CAT: 30 MCQs
- ENDOCRINE PATHOLOGY
- Endocrine and Metabolic Pathology MCQs: Practice Questions
- Internal Medicine (MBIM 4100) main exam, Paper One: 3 July 2019
- Endocrinology and Gastroenterology Question Bank: 12 Clinical MCQs
- Chemical Pathology Practice Examination
- Basic Pharmacology - Study Guide
Practice questions on Graves Disease
A 35-year-old woman undergoes a thyroidectomy for Graves disease. Histologic examination of the thyroid gland shows follicular epithelial cells that are tall and columnar instead of the normal cuboidal shape. This finding is best explained by which of the following processes?
- Neoplastic transformation
- Hyperplasia with hypertrophy
- Dysplasia
- Metaplasia
- Anaplasia ANSWER: B
Answer: B. In Graves disease, excessive TSH receptor stimulation leads to both increased number (hyperplasia) and increased size (hypertrophy) of follicular cells, causing them to become tall and columnar. This is a physiologic adaptation to hormonal stimulation, not a neoplastic or metaplastic change.
Graves disease is driven primarily by antibodies to the:
- Thyroglobulin
- TSH receptor
- Insulin receptor
- ACTH receptor
- PTH receptor ✅ Answer: B
Answer: A. Graves' disease is an autoimmune condition caused by stimulating antibodies directed against the TSH receptor.
Which of the following is NOT a typical feature of Graves' disease?
- Toxic nodular goitre
- Antibodies to TSH receptor
- Diffuse goitre
- Exophthalmos
Answer: A. Graves' disease is an autoimmune disorder causing diffuse toxic goitre and hyperthyroidism, typically mediated by TSH receptor antibodies (TRAb). Exophthalmos is a characteristic feature. Toxic nodular goitre (Plummer's disease) is a different cause of hyperthyroidism. ---
Toxic multinodular goiter (Plummer's disease) differs from Graves' disease in that
- It is more common in young women
- It is associated with TSI antibodies
- It causes exophthalmos
- It occurs in older patients with long-standing goiter and lacks TSI antibodies and eye signs
Answer: D. Toxic MNG = autonomous function of multiple nodules in a pre-existing goiter. Occurs in iodine-deficient areas in older patients. No TSI, no ophthalmopathy. Treated with radioiodine or surgery. Hot nodules on Tc-99m scan. ---
Which antibody directly causes hyperthyroidism in Graves' disease?
- Anti-TPO antibody
- Anti-thyroglobulin antibody
- TSH receptor-stimulating immunoglobulin (TSI)
- Anti-nuclear antibody
Answer: C. TSI binds and continuously activates TSH receptors causing unregulated thyroid hormone production. Unique features: exophthalmos and pretibial myxedema. ---
Toxic multinodular goiter (Plummer's disease) differs from Graves' disease in that
- Graves' disease is characterized by autoimmune antibodies stimulating the TSH receptor.
- Toxic multinodular goiter is associated with exophthalmos.
- Graves' disease is always accompanied by diffuse thyroid enlargement.
- Toxic multinodular goiter typically has a more rapid onset.
Answer: A. Graves' disease is an autoimmune disorder where antibodies (Thyroid-Stimulating Immunoglobulins, TSI) bind to and stimulate the TSH receptor, leading to diffuse thyroid overactivity, goiter, and often extrathyroidal manifestations like exophthalmos. In toxic multinodular goiter, one or more nodules within the thyroid gland autonomously produce excess thyroid hormone, typically without the autoimmune features or exoph