Differential Diagnosis for Subacute Thyroiditis
- Single most likely diagnosis
- Subacute thyroiditis (de Quervain's thyroiditis): This is the most likely diagnosis due to its characteristic presentation of neck pain, tenderness, and transient hyperthyroidism followed by hypothyroidism, which eventually resolves to euthyroidism. The condition is often preceded by a viral infection.
- Other Likely diagnoses
- Acute thyroiditis: Presents with severe neck pain, fever, and tenderness, which can mimic subacute thyroiditis but is less common and often associated with bacterial or fungal infections.
- Hashimoto's thyroiditis: An autoimmune condition that can cause thyroid inflammation and hypothyroidism, sometimes presenting with a similar clinical picture to subacute thyroiditis but typically without the initial hyperthyroid phase.
- Silent thyroiditis: A form of autoimmune thyroiditis that can cause transient hyperthyroidism followed by hypothyroidism, similar to subacute thyroiditis, but usually without significant neck pain or tenderness.
- Do Not Miss diagnoses
- Thyroid lymphoma: Although rare, it can present with rapid thyroid enlargement and symptoms similar to subacute thyroiditis, making it crucial to consider due to its severe implications and need for prompt treatment.
- Anaplastic thyroid cancer: A highly aggressive form of thyroid cancer that can cause rapid thyroid enlargement, pain, and symptoms overlapping with subacute thyroiditis, necessitating its consideration due to the urgent need for intervention.
- Riedel's thyroiditis: A rare form of chronic thyroiditis characterized by a hard, fibrotic thyroid gland that can cause compressive symptoms and mimic the pain of subacute thyroiditis, though it typically does not resolve spontaneously.
- Rare diagnoses
- Radiation-induced thyroiditis: Can occur after radiation therapy to the neck and presents with thyroid inflammation and dysfunction, similar to subacute thyroiditis, but is directly related to the radiation exposure.
- Amiodarone-induced thyroiditis: Associated with the use of the medication amiodarone, which can cause both hypothyroidism and hyperthyroidism due to its high iodine content and direct toxic effects on the thyroid gland.
- Eosinophilic thyroiditis: A rare condition characterized by eosinophilic infiltration of the thyroid gland, which can present with thyroid dysfunction and inflammation, though it is exceedingly uncommon.