From the Guidelines
Graves' disease diagnosis is primarily based on clinical evaluation, blood tests, and imaging studies, with a focus on detecting autoantibodies such as thyroid-stimulating immunoglobulin (TSI) or thyroid receptor antibody (TRAb) to provide a definitive diagnosis. The diagnostic process begins with a thorough assessment of symptoms such as unexplained weight loss, heat intolerance, anxiety, tremors, and bulging eyes (exophthalmos) [ 1 ]. Blood tests are essential and include thyroid function tests showing elevated levels of thyroid hormones (T3 and T4) with suppressed thyroid-stimulating hormone (TSH).
Key Diagnostic Steps
- Thyroid function tests to evaluate T3, T4, and TSH levels
- TSI or TRAb tests to detect autoantibodies
- Radioactive iodine uptake scan to visualize increased uptake throughout the thyroid gland
- Thyroid ultrasound to rule out other causes of hyperthyroidism
- Ophthalmologic examination for patients with eye symptoms to assess for Graves' ophthalmopathy Physical examination findings of ophthalmopathy or thyroid bruit are diagnostic of Graves’ disease and should prompt early endocrine referral [ 1 ]. Early diagnosis is crucial as untreated hyperthyroidism can lead to serious complications including heart problems and osteoporosis. The autoimmune nature of Graves' disease explains why antibody testing is so valuable—these antibodies mimic TSH, continuously stimulating the thyroid to produce excess hormones.
From the Research
Diagnosis of Graves' Disease
- The diagnosis of Graves' disease is based on the typical clinical picture and laboratory thyroid panel, including measurements of serum levels of anti-TSH-receptor antibodies (TRAb) and thyroid ultrasonography 2.
- The first-line biological assessment in suspected thyrotoxicosis is thyroid-stimulating hormone (TSH), followed by free T4 and possibly free T3 assays to assess biological severity and monitor treatment efficacy 3.
- Positive diagnosis of Graves' disease after biological confirmation of thyrotoxicosis does not always require complementary etiological examinations if clinical presentation is unambiguous, but first-line anti-TSH-receptor (TSH-R) antibody screening is recommended for its good intrinsic performance and ease of access 3.
Role of TRAbs in Diagnosis and Management
- Establishment of elevated serum levels of TRAbs by competitive binding assay or cell-binding assay has a unique role in diagnosis and management of Graves' disease, especially in differential diagnosis, therapy selection, prognostication, and evaluation of thyroid function during pregnancy 4.
- Inclusion of TRAbs in the diagnostic algorithm can improve the cost-effectiveness of Graves' disease management 4.
- TRAbs are also useful in monitoring the response to treatment and predicting the risk of relapse 4.
Diagnostic Tests
- Thyroid ultrasonography is an important diagnostic test for Graves' disease, as it can help to assess the size and structure of the thyroid gland 2.
- Scintigraphy is reserved for rare cases of Graves' disease with negative antibody findings or when another etiology is suspected 3.
- Iodine-123 (I-123) thyroid uptake and scan can be used to assess thyroid function and diagnose Graves' disease 5.
Clinical Presentation
- Graves' disease is characterized by hyperthyroidism, orbitopathy, dermopathy, and acropachy, and is caused by autoimmune thyrotropin receptor antibody-mediated activation of the thyroid 5, 6.
- The clinical presentation of Graves' disease can be variable, but typically includes symptoms such as weight loss, palpitations, and exophthalmos 6.