Background: To identify clinical and laboratory factors contributing to the diagnosis of giant cell arteritis (GCA) and develop a diagnostic algorithm for the evaluation of GCA.
Methods: Retrospective review of 213 consecutive cases of temporal artery biopsy (TAB) seen at a single academic center over a 10-year period (2000–2009). Pathologic specimens were re-reviewed and agreement between the original and second readings was assessed. A composite clinical suspicion score was created by adding 1 point for each of the following criteria: anterior extracranial circulation ischemia, new onset headache, abnormal laboratory results (erythrocyte sedimentation rate, C-reactive protein (CRP), or platelet count), jaw claudication, abnormal or tender superficial temporal artery, constitutional symptoms, and polymyalgia rheumatica; one point was subtracted if a comorbid condition could explain a criterion.
Results: Of the 204 TABs analyzed, pathologic findings were confirmatory in 49 (24.0%) and suggestive in 12 (5.9%). TAB-positive patients were more likely to be older (age 75.2 ± 7.8 vs 69.7 ± 11.0 years, P = 0.0002), complain of jaw claudication (relative-risk = 3.26, P = 0.0014), and have thrombocytosis (relative–risk = 3.3, P = 0.0072) and elevated CRP (relative-risk = 1.8, P = 0.037). None of the patients with a clinical score less than 2 had a positive TAB. Diabetes mellitus and kidney disease were often the explanation for the symptoms and abnormal clinical finding(s) that led to a negative TAB.
Conclusions: We propose a clinical algorithm that is highly predictive for a positive TAB and can be valuable in the evaluation process of suspected cases of GCA.
Departments of Ophthalmology (MAE-D, LC, ADP, TJC, SSS, MTB), Pathology (ADP, TJC), Biostatistics and Bioinformatics (SSS), and Neurology (MTB), Duke Eye Center and Duke University Medical Center, Durham, North Carolina.
Address correspondence to M. Tariq Bhatti, MD, Departments of Ophthalmology and Neurology, Duke University Eye Center, 2351 Erwin Road, DUMC 3802, Durham, NC 27710-3802; E-mail: email@example.com
Supported by unrestricted departmental research grant from Research to Prevent Blindness, Inc.
M. A. El-Dairi is a consultant for Prana Pharmaceuticals. M. T. Bhatti is a consultant for Novartis pharmaceuticals. The remaining authors report no conflicts of interest.
Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the full text and PDF versions of this article on the journal's Web site (www.jneuro-ophthalmology.com).