Ali S. Raja1 and Fernanda Bellolio2 1 Department of Emergency Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA 2 Department of Emergency Medicine, Mayo Clinic, Rochester, MN, USA Temporal arteritis, also known as giant cell arteritis, is an inflammatory condition characterized by focal, granulomatous changes of branches of the carotid artery that lead to vessel damage, stenosis, and eventual occlusion. Histopathologic findings from temporal artery biopsies include multinucleated giant cells, necrotic tissue, and lymphocytic infiltration of the inflamed vessel wall. The classic description of the clinical manifestations of temporal arteritis includes a new temporal headache that can wax and wane, jaw claudication (and even trismus‐like symptoms), and visual symptoms (from floaters to transient monocular vision loss). Table 52.1 American College of Rheumatology (ACR) diagnostic criteria for temporal arteritis Source: Data from [2]. Temporal arteritis is a disease process of older adults and is reported as the most common systemic vasculitis in this age group, estimated to occur in approximately 23 per 100,000 women aged 50 years and older, and approximately one‐third as many men. While the mortality associated with temporal arteritis is not different from that for those without the condition, its principal morbidity is the risk for permanent visual impairment, as greater than 20% of patients with temporal arteritis develop permanent visual loss.1 The American College of Rheumatology (ACR) diagnostic criteria are listed in Table 52.1.2 Patients with three of the five criteria are considered to have temporal arteritis; however, it is usually a heightened clinical suspicion that prompts a biopsy that leads to the diagnosis. While treatments are available that markedly decrease the likelihood of developing permanent visual loss, it is sometimes difficult to determine which patients should receive a biopsy in order to make the diagnosis. Thus, research into the diagnosis of temporal arteritis has focused on the historical features, physical exam findings, and laboratory results that may help determine which patients should be treated and subsequently referred for temporal artery biopsy. Newer research has focused on the use of ultrasound as an additional diagnostic adjunct for the diagnosis of the disease. Which factors in a patient’s history, physical exam, and laboratory values are predictive of having temporal arteritis? Two large studies have examined signs and symptoms associated with temporal arteritis.3,4 Both studies included only patients who had undergone biopsies of the temporal artery, and thus both used biopsy as their criterion standard. The prevalence of temporal arteritis in patients sent for temporal artery biopsy in these studies ranged from 33% to 39%, but it should be noted that the prevalence of temporal arteritis in all patients older than 50 years has been estimated to be 1 in 500.5 Neither study was able to assess the interobserver reliability of the clinical findings as they were typically taken from retrospective chart reviews. Table 52.2 shows the clinical variables from each study associated with the diagnosis of temporal arteritis. Table 52.2 Clinical findings and laboratory findings in the diagnosis of temporal arteritis
Chapter 52
Temporal Arteritis
Background
Clinical question
Variable
Positive likelihood ratio (LR+)
Negative likelihood ratio (LR−)
Jaw claudication3
4.2 (2.8–6.2)
0.7 (0.6–0.8)
Diplopia3
3.4 (1.3–8.6)
0.95 (0.9–0.99)
Beading of temporal artery3
4.6 (1.1–18.4)
0.93 (0.88–0.99)
Prominent or enlarged temporal artery3
4.3 (2.1–8.9)
0.6 (0.5–0.9) Full access? Get Clinical Tree
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