Does this patient have temporal arteritis?

CONTEXT: 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.

OBJECTIVE: To determine the accuracy of historical features, physical examination, and erythrocyte sedimentation rate (ESR) in diagnosis of TA.

DATA SOURCES: 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.

STUDY SELECTION: 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.

DATA EXTRACTION: Both authors independently reviewed each study to determine eligibility, abstracted data using a standardized instrument, and classified study quality using predetermined criteria.

DATA SYNTHESIS: 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).

CONCLUSIONS: 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.