Thyroid & parathyroid


Subacute thyroiditis

Topic Completed: 1 March 2009

Minor changes: 2 July 2021

Copyright: 2003-2021,, Inc.

PubMed Search: subacute thyroiditis

Shahid Islam, M.D., Ph.D.
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Cite this page: Islam S. Subacute thyroiditis. website. Accessed October 27th, 2021.
Definition / general
  • Inflammation of thyroid gland that includes granulomas
  • Rare, much less common than Hashimoto thyroiditis but most common cause of thyroid pain
  • Painful swallowing (odynophagia), sore throat, thyroid region tenderness, fever, fatigue, malaise
  • Also called de Quervain thyroiditis or granulomatous thyroiditis
  • Etiology may be systemic viral infection, since associated with epidemics of measles, mumps, Coxsackie, adenovirus and influenza
Clinical features
  • Self limited, usually resolves in 6 - 8 weeks with only 1% having permanent hypothyroidism
  • May be transient hypothyroidism at 2 - 8 weeks
  • High T3 / T4 (initially), elevated sedimentation rate (ESR), suppression of iodine uptake
  • Later hypothyroidism and antithyroid antibodies
  • After weeks to months, patients become euthyroid
Radiology images

Contributed by Ayana Suzuki, C.T.

Hypoechoic nodule

Case reports
Gross description
  • Focal to diffuse enlargement of thyroid gland up to 2× normal size
  • May be asymmetric with nodules of variable size; may be firm, but does not adhere to surrounding structures
Microscopic (histologic) description
  • Early: neutrophils and destruction of follicles with colloid depletion
  • Later: noncaseating granulomas surround follicles and engulf colloid
  • Late: fibrosis
Microscopic (histologic) images

Contributed by Mark R. Wick, M.D.

Images hosted on other servers:

With fibrosis

Giant cells, inflammatory cells and destruction of thyroid follicles

Giant cells, inflammatory cells and destruction of thyroid follicles

Giant cells, inflammatory cells and destruction of thyroid follicles

Positive stains:

Scant epithelioid cells

Multinucleated giant cells

Epithelioid cells and lymphocytes

Virtual slides

Images hosted on other servers:

Acute (subacute) nonsuppurative thyroiditis

Measles thyroiditis

Chronic inflammatory infiltrate

Cytology description
  • Cellular smears with clustered epithelioid cells, fibrous fragments with enmeshed inflammatory cells, scattered lymphocytes, histiocytes and neutrophils, occasional multinucleated giant cells containing up to 100 nuclei and ingesting colloid or neutrophils; also occasionally thick colloid with central cracks and frayed edges (Diagn Cytopathol 2006;34:18)
Cytology images

Contributed by Ayana Suzuki, C.T.

Giant cell

Differential diagnosis
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