### Date : 2024-06-24 08:44 ### Topic : Subacute Granulomatous Thyroiditis #medicine #endocrinology #thyroid ---- ### De Quervain's Thyroiditis Overview **De Quervain's thyroiditis**, also known as **subacute granulomatous thyroiditis** or **subacute thyroiditis**, is an inflammatory condition of the thyroid gland that typically follows a viral infection. It is characterized by neck pain, thyroid tenderness, and transient hyperthyroidism, followed by hypothyroidism, and eventually returning to normal thyroid function. ### Etiology - **Causative Agent:** Often follows a viral upper respiratory infection. Common viruses associated with this condition include Coxsackievirus, mumps, adenovirus, and echovirus. - **Pathophysiology:** Viral infection leads to an inflammatory response in the thyroid gland, causing damage to thyroid follicles and release of stored thyroid hormones. ### Pathophysiology 1. **Inflammation:** - Viral infection triggers an immune response, leading to infiltration of immune cells (e.g., lymphocytes, macrophages) into the thyroid gland. - This causes granulomatous inflammation with giant cells and disruption of thyroid follicles. 2. **Thyroid Hormone Release:** - Inflammation and follicular disruption lead to the release of preformed thyroid hormones (T3 and T4) into the bloodstream, causing transient hyperthyroidism. 3. **Phases of the Disease:** - **Hyperthyroid Phase:** Initial phase where excess thyroid hormones are released. - **Euthyroid Phase:** As hormone levels normalize, the thyroid gland may temporarily function normally. - **Hypothyroid Phase:** Depleted hormone stores and impaired hormone synthesis lead to hypothyroidism. - **Recovery Phase:** Thyroid function typically returns to normal over weeks to months. ### Clinical Features **Symptoms:** - **Neck Pain:** Sudden onset of pain in the front of the neck, often radiating to the jaw, ears, or chest. - **Tender Thyroid Gland:** Thyroid gland is tender to palpation. - **Systemic Symptoms:** Fever, fatigue, malaise, and myalgia. - **Thyroid Dysfunction Symptoms:** - **Hyperthyroid Phase:** Palpitations, heat intolerance, weight loss, anxiety, and tremors. - **Hypothyroid Phase:** Fatigue, cold intolerance, weight gain, and depression. **Signs:** - **Thyroid Tenderness:** Pain on palpation of the thyroid gland. - **Fever:** Low-grade fever is common. ### Diagnosis **Clinical Evaluation:** - Based on characteristic symptoms and physical examination findings. **Laboratory Tests:** 1. **Thyroid Function Tests:** - **Hyperthyroid Phase:** Low TSH, elevated free T4 and T3. - **Hypothyroid Phase:** Elevated TSH, low free T4. - **Euthyroid Phase:** Normal TSH and thyroid hormone levels. 2. **Inflammatory Markers:** - **Elevated ESR (Erythrocyte Sedimentation Rate):** Typically elevated, indicating inflammation. - **Elevated CRP (C-Reactive Protein):** May also be elevated. 3. **Thyroid Antibodies:** - **Negative Thyroid Antibodies:** Differentiates from autoimmune thyroiditis (e.g., Hashimoto's thyroiditis) where thyroid antibodies are typically positive. **Imaging:** - **Radioactive Iodine Uptake (RAIU):** - Low uptake during the hyperthyroid phase, differentiating it from other causes of hyperthyroidism (e.g., Graves' disease). ### Example Case Study **Patient Profile:** - **Name:** Jee Hoon Ju - **Age:** 40 - **Occupation:** Teacher **Medical History:** - Recent upper respiratory infection. - Sudden onset of neck pain radiating to the jaw and ears, along with fatigue and fever. **Clinical Evaluation:** - **Physical Examination:** Tender thyroid gland on palpation. - **Symptoms:** Weight loss, palpitations, and tremors. **Laboratory Tests:** - **TSH:** Suppressed. - **Free T4 and T3:** Elevated. - **ESR:** Elevated. - **Thyroid Antibodies:** Negative. **RAIU Test:** - **Low Uptake:** Consistent with de Quervain's thyroiditis. **Diagnosis:** Based on clinical presentation, laboratory findings, and imaging, Jee Hoon Ju is diagnosed with de Quervain's thyroiditis. ### Management 1. **Pain and Inflammation Management:** - **NSAIDs (Nonsteroidal Anti-Inflammatory Drugs):** Ibuprofen or naproxen for mild to moderate pain and inflammation. - **Corticosteroids:** Prednisone for severe pain or if symptoms do not improve with NSAIDs. 2. **Thyroid Dysfunction Management:** - **Beta-Blockers:** Propranolol or atenolol for symptomatic relief of hyperthyroid symptoms (e.g., palpitations, tremors). - **Thyroid Hormone Replacement:** Levothyroxine for hypothyroid phase if symptomatic or if TSH is significantly elevated. 3. **Monitoring:** - Regular follow-up to monitor thyroid function tests and adjust treatment as necessary. - Gradual tapering of corticosteroids once symptoms improve. ### Prognosis - **Self-Limiting:** Most patients recover completely within a few months. - **Thyroid Function:** Typically returns to normal, though some patients may develop permanent hypothyroidism and require ongoing thyroid hormone replacement. ### Conclusion De Quervain's thyroiditis is an inflammatory thyroid condition often following a viral infection, characterized by neck pain, transient hyperthyroidism, and subsequent hypothyroidism. Diagnosis is based on clinical features, laboratory tests, and imaging. Management focuses on relieving pain and inflammation, managing thyroid dysfunction, and regular monitoring. Understanding the phases and appropriate treatment strategies can help achieve optimal outcomes for patients with de Quervain's thyroiditis.