Temporal (Giant Cell) Arteritis can be diagnosed using a classification tree approach.
top level |
second level |
third level |
fourth level |
diagnosis |
clinically abnormal temporal arteries |
age at onset >= 50 years |
|
|
TA |
|
age at onset < 50 years |
|
|
non-TA |
clinically normal temporal arteries |
artery biopsy positive |
age at onset >= 50 years |
|
TA |
|
|
age at onset < 50 years |
|
non-TA |
|
artery biopsy negative |
claudication present |
age at onset >= 50 years |
TA |
|
|
|
age at onset < 50 years |
non-TA |
|
|
claudication absent |
|
non-TA |
Surrogate criteria:
(1) If the clinical status of the temporal arteries is unknown, then the presence or absence of a tender scalp or scalp nodules may be used.
(2) If an artery biopsy is not available, then the presence or absence of a new headache may be used.
Criteria |
Comment |
age at disease onset >= 50 years |
Occurs only rarely before the age of 50. |
new headache |
new onset or new type of localized pain in the head |
temporal artery abnormality |
temporal artery tenderness to palpation, or decreased pulsation, unrelated to arteriosclerosis of cervical arteries |
claudication of jaw, tongue or on deglution |
development or worsening of fatigue or discomfort in muscles of mastication, tongue or swallowing muscles while eating |
abnormal temporal artery biopsy |
Artery shows vasculitis with predominance of mononuclear cell infiltration or granulomatous inflammation, usually with multinucleated giant cells. The involvement is segmental, so an adequate biopsy is needed for diagnosis. |
scalp tenderness or nodules |
development of tender areas or nodules over the scalp, away from the temporal artery or other cranial arteries |
Patient Subsets |
Findings |
TA patients |
age >= 50 years at onset; clinically abnormal temporal arteries |
|
age >= 50 years at onset; artery biopsy positive; clinically normal temporal arteries |
|
age >= 50 years at onset; claudication; clinically normal temporal arteries; artery biopsy negative |
non-TA patients |
clinically normal temporal arteries; negative artery biopsy; no claudication |
|
age < 50 years at onset; claudication present; clinically normal temporal arteries; negative artery biopsy |
|
age < 50 years at onset; clinically normal temporal arteries; positive artery biopsy |
|
age < 50 years at onset; clinically abnormal temporal arteries |
Performance:
• The sensitivity 95.3% and specificity 90.7%
Specialty: Immunology/Rheumatology
ICD-10: ,