Clinicians must be able to confidently diagnose temporal arteritis (TA),
since failure to make a correct diagnosis may lead to irreversible visual
loss as well as inappropriate evaluation and treatment of headache, fatigue,
and other potential presenting symptoms. The diagnostic value of particular
signs and symptoms among patients with suspected TA is unknown.
To determine the accuracy of historical features, physical examination,
and erythrocyte sedimentation rate (ESR) in diagnosis of TA.
We performed a MEDLINE search of English-language articles published
between January 1966 and July 2000 and a hand search of bibliographies of
retrieved articles, previous reviews, monographs, and textbooks.
Studies that provided detailed clinical information on patients who
had been referred for temporal artery biopsy. Of 114 studies retrieved, 41
met our inclusion criteria; 21 included both biopsy-positive and biopsy-negative
patients and formed the core of our review.
Both authors independently reviewed each study to determine eligibility,
abstracted data using a standardized instrument, and classified study quality
using predetermined criteria.
The prevalence of TA in the general population is less than 1%. However,
in our 21 core studies, 39% of patients referred for temporal artery biopsy
had positive results. The only 2 historical features that substantially increased
the likelihood of TA among patients referred for biopsy were jaw claudication
(positive likelihood ratio [LR], 4.2; 95% confidence interval [CI], 2.8-6.2)
and diplopia (positive LR, 3.4; 95% CI, 1.3-8.6). The absence of any temporal
artery abnormality was the only clinical factor that modestly reduced the
likelihood of disease (negative LR, 0.53; 95% CI, 0.38-0.75). Predictive physical
findings included temporal artery beading (positive LR, 4.6; 95% CI, 1.1-18.4),
prominence (positive LR, 4.3; 95% CI, 2.1-8.9), and tenderness (positive LR,
2.6; 95% CI, 1.9-3.7). Normal ESR values indicated much less likelihood of
disease (negative LR for abnormal ESR, 0.2; 95% CI, 0.08-0.51).
A small number of clinical features are helpful in predicting the likelihood
of a positive temporal artery biopsy among patients with a clinical suspicion
of disease; the most useful finding is a normal ESR, which makes TA unlikely.