Giant cell arteritis (RZA) can be classified according to the ACR criteria* :
Main criteria
- Age at onset of disease >50 years
- New onset of localized headache
- Localized tenderness or attenuated pulsation of a temporal artery (without atherosclerotic cause)
- ESR (erythrocyte sedimentation rate) > 50 mm/hour.
- Evidence of vasculitis by arterial biopsy (vasculitis/vascular inflammation: mononuclear cell infiltration or granulomatous vascular inflammation, usually with evidence of giant cells) [specificity: 97%].
A diagnosis of RZA can be made if at least three of the five major criteria are present.
* American College of Rheumatology (ACR)
Additional criteria
- Arteriitic vascular complications(most commonly the extracranial arteries of the head (external carotid artery), including the superficial temporal artery (temporal arteritis).
- Other neuroophthalmologic symptoms: Diplopia (double vision, double images), veil vision, amaurosis fugax (lat. fleeting blindness; regression of blindness within minutes).
- Polymyalgic complaints may precede RZA.
- The diagnosis is usually made histologically (fine tissue) by temporal artery biopsy.
Caution!The diagnosis of RZA is made in the synopsis of symptoms, clinical findings and results of laboratory and medical device diagnostics. The above ACR criteria should not be misinterpreted as clinical diagnostic criteria.
