Giant cell (temporal) arteritis: No laboratory test or physical finding is pathognomic

Référence

Van der Geest KS, Sandovici M, Brouwer E, Mackie SL. Diagnostic accuracy of symptoms, physical signs, and laboratory tests for giant cell arteritis. A systematic review and meta-analysis. JAMA Intern Med 2020;180(10):1295-1304.

Sommaire

These researchers searched 3 databases for trials and observational studies, identifying 68 English-language studies of 14,037 patients investigated for possible GCA. Two researchers independently selected studies for inclusion; data were extracted by one researcher and checked by a second researcher. Risk of bias was assessed independently by 2 researchers, who found selection bias to be likely among the studies. The other issue is gold standard: Although temporal artery biopsy was used in most studies, some studies used clinical diagnosis as the reference standard. Individually, no single finding could confirm or refute the diagnosis. The likelihood ratio for findings associated with the diagnosis were all in the small to moderate range, meaning their presence somewhat predicts GCA; these include jaw claudication, temporal tenderness, temporal artery loss of pulse, temporal artery thickening, platelet count greater than 400,000/microliter, and an ESR greater than 100 mm/h. An ESR less than 40 mm/h was the best predictor of the absence of GCA, with a negative likelihood ratio of 0.18 (95% CI 0.08 - 0.44).