The term thyroiditis encompasses a diverse group of disorders characterized by some form of thyroid inflammation. They include conditions that cause acute illness with severe thyroid pain (eg, subacute thyroiditis and infectious thyroiditis), and conditions in which there is no clinically evident inflammation and the illness is manifested primarily by thyroid dysfunction or goiter (eg, painless thyroiditis and fibrous [Riedel's] thyroiditis)].

These disorders can be categorized in several ways: according to their known or suspected etiology, their pathology, or their clinical features.

A clinically useful was to categorize thyroiditis is whether it is associated with thyroid pain and tenderness, because the presence or absence of those findings dominates the major diagnostic considerations.

Causes of thyroiditis according to the presence or absence of pain and tenderness
Disorder Synonyms or causes
Thyroid pain and tenderness
Subacute thyroiditis Subacute granulomatous thyroiditis
Subacute nonsuppurative thyroiditis
de Quervain's thyroiditis
Infectious thyroiditis Acute or chronic thyroiditis
Radiation-induced thyroiditis  
Palpation- or trauma-induced thyroiditis  
No thyroid pain and tenderness
Painless thyroiditis Silent thyroiditis
Lymphocytic thyroiditis with spontaneously resolving hyperthyroidism
Subacute lymphocytic thyroiditis
- Occurring postpartum Postpartum thyroiditis
- Associated with drugs Interferon-alpha
Tyrosine kinase inhibitors
Chronic lymphocytic thyroiditis Hashimoto's thyroiditis
- Postpartum exacerbation Postpartum thyroiditis
Amiodarone-associated thyroiditis  
Fibrous thyroiditis Riedel's thyroiditis
Invasive thyroiditis









Content 12

Content 9





Physical Exam


Laboratory Tests



Essentail Criteria to Establish Diagnosis



Content 4

Content 3

Content 11



USMLE Reviewer (Subscription Required)