Giant cell arteritis

Giant cell arteritis (GCA) is a common granulomatous vasculitis affecting large to medium sized arteries. It may also be known as temporal arteritis or cranial arteritis, given its propensity to involve the extra-cranial carotid artery branches such as the temporal artery

GCA is the most common primary systemic vasculitis. It has an incidence of 200 per million population per year 6. Typically affects older individuals (usually older than 50 years of age, with a peak age of 70-80 years 3). There is a recognised female predilection.

It is histologically similar to other large vessel vasculitides (such as Takayasu arteritis) showing granulomatous inflammation of arteries with infiltration predominantly by histiocytes, lymphocytes, and multinucleated giant cells. The characteristic multinucleated giant cells are only found in ~50% of cases 1.


Can potentially affect any large-to-medium sized vessels, affecting the aorta (~20% of cases 7) and its major branches, particularly the extracranial branches of the carotid artery 6.

  • serum erythrocyte sedimentation rate (ESR): markedly raised
  • serum C-reactive protein (CRP): often markedly raised
  • increased diameter of the TA and hypoechoic wall thickening (halo)
    • more specific for GCA if bilateral 8
    • reversible under corticosteroid treatment
  • stenosis may be present but is not a specific sign for GCA 8
CT angiography
  • may be useful for assessing luminal abnormalities, such as stenoses, occlusions, dilations, and aneurysm formation
  • may also show wall thickening of affected segments, calcification and mural thrombi
  • T1 C+ (Gd)
    • the best sequence for assessment, and is reported to show mural inflammation very well 2,4
    • mean wall thickness increased in the affected region
    • luminal diameter decreased in the affected region
    • reported approximate sensitivity and specificity is at 80 and 97% respectively 2 

Often treated with corticosteroid therapy.

Imaging differential considerations include

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Article information

rID: 10936
System: Vascular
Section: Pathology
Tag: cases
Synonyms or Alternate Spellings:
  • Temporal arteritis
  • Giant cell arteritis (GCA)
  • Maladie de Horton
  • Horton disease
  • Cranial arteritis

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Cases and figures

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    Case 1: temporal arteritis
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    Case 2: on right
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    Case 3: baseline study
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    Case 3 :changes after therapy
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    Case 4
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