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Key Points and Definitions
` Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are systemic
vasculitides that primarily affect large and medium-sized vessels.
• GCA can present with both cranial and extracranial manifestations and is more
common in individuals of Northern European descent who are older than 50
years of age.
• TAK is more common in younger women and causes granulomatous
inflammation of the aorta and its branches.
Table 1. Definitions of Selected Terms Used in the
Recommendations and Ungraded Position
Statements for GCA and TAK
Term Definition
Disease States
Suspected disease Clinical symptoms or signs suggestive of GCA/TAK and not
explained by other conditions
Active disease New, persistent, or worsening clinical signs and/or symptoms
attributed to GCA/TAK and not related to prior damage
Severe disease Vasculitis with life-/organ-threatening manifestations (e.g.,
vision loss, cerebrovascular ischemia, cardiac ischemia, limb
ischemia)
Non-severe disease Vasculitis without life-/organ-threatening manifestations (e.g.,
constitutional symptoms, headache, jaw claudication, symptoms
of polymyalgia rheumatica)
Remission Absence of clinical signs or symptoms attributed to active
GCA/TAK, on or off of immunosuppressive therapy
Refractory disease Persistent active disease despite an appropriate course of
immunosuppressive therapy
Relapse Recurrence of active disease following a period of remission
Cranial ischemia Visual and neurological involvement including amaurosis fugax,
vision loss, and stroke
Disease Assessments
Clinical monitoring Assessing for clinical signs and symptoms of active disease,
obtaining 4 extremity blood pressures, and obtaining clinical
labs including inflammatory markers
Inflammatory markers Erythrocyte sedimentation rate, C-reactive protein
Non-invasive imaging Computed tomography angiogram, magnetic resonance
angiogram, positron emission tomography scan, vascular
ultrasound, magnetic resonance imaging of temporal and scalp
arteries
Invasive imaging Conventional catheter-based angiogram
