[1][2][3][4][5][6][7] The temporal classification of thyroiditis includes presentation of symptoms in an acute, subacute, or chronic manner.
[1][2][3][4][5] In the thyrotoxic stage, individuals usually complain of fever, myalgia, and may have associated anterior neck pain among other symptoms.
[2][4][5] Drug-induced thyroiditis can occur in individuals receiving certain therapies such as amiodarone, interferon-alpha, lithium, tyrosine-kinase inhibitors, and immunotherapies among other drugs.
The damage to the follicles impairs ability to produce and secrete thyroid hormones which then leads to a hypothyroid phase.
[1][2][3][4][5][6][8] The presenting symptom is usually anterior neck pain that may be unilateral or bilateral with radiation to jaw or ears.
[2] Most people return to normal thyroid function within one year of symptom onset; however, between 5-15% of individuals develop permanent hypothyroidism.
[4][5][7] In the hypothyroid phase, patient may experience cold intolerance, fatigue, weight gain, or depression.
[5] The diagnosis of subacute thyroiditis can be made clinically by eliciting risk factors, associated symptoms, and physical examination.
[1][2][3] Additionally, radioactive iodine uptake (RAIU) and scan can be performed in the thyrotoxic stage to help differentiate between other causes of thyrotoxicosis.
Inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are elevated.
[1][2][3][4][5] RAIU will be low in the thyrotoxic phase which helps to distinguish subacute granulomatous thyroiditis from other cause of thyrotoxicosis such as Graves' disease.
[4][5] It can be distinguished from subacute granulomatous thyroiditis by lack of pain, presence of TPO or thyroglobulin (Tg) antibodies, and normal inflammatory markers.
[2]First line treatment for pain is high doses of nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen.
[2][3][4][5] Annual followup is recommended for these individuals due to risk of recurrence and development of permanent hypothyroidism.