Diagnostic Accuracy of ESR, CRP, and Platelet Count (and Their Combinations) for Giant Cell Arteritis: A Meta-analysis of 14,000 Patients
Sharath Chandra Anne1, Shradha Kakde2, Meghnath Kakde3, Anas Mansour4, Ahmed Harb4, Meghana Chennupati5, Harshawardhan Ramteke6, Rakhshanda Khan6
1pinnamaneni siddharta medical college, 2MGM medical college and hospital, 3smt.kashibai navale medical college and general hospital, 4Faculty of Medicine, Al-Azhar University, Cairo, Egypt, 5Mamata Academy of Medical Sciences, 6Ayaan Institute of medical sciences
Objective:
To determine the pooled diagnostic accuracy of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and platelet count—individually and in combination—for the diagnosis of giant cell arteritis (GCA), using biopsy or validated clinical diagnosis as reference standards.
Background:
Acute phase reactants such as ESR and CRP are routinely used to evaluate suspected GCA, but their comparative diagnostic value and optimal combinations remain uncertain. Platelet count, often elevated in systemic inflammation, may add specificity. A quantitative synthesis of these markers can refine clinical triage before temporal artery biopsy or vascular imaging
Design/Methods:
A PRISMA-DTA–based meta-analysis evaluated ESR, CRP, and platelet accuracy in suspected GCA using bivariate models, examined “both normal” and “triple elevation” combinations, and applied QUADAS-2.0 for quality assessment.
Results:
Fourteen studies comprising 14,037 patients (4,277 biopsy-confirmed GCA) were included. Pooled estimates showed: ESR ≥50 mm/hr sensitivity 84% (81–87) and specificity 41% (36–47); CRP ≥20 mg/L sensitivity 89% (86–91) and specificity 43% (39–47); platelets ≥400 × 10⁹/L sensitivity 58% (53–63) and specificity 80% (75–84). The “both ESR and CRP normal” profile was rare (3–5% of GCA) with high rule-out value (specificity 97%, negative LR ≈ 0.15), whereas “triple elevation” (ESR + CRP + platelets) yielded specificity 84% and positive LR ≈ 2.6. CRP and platelets had the highest AUCs (0.72–0.76). Heterogeneity was moderate, largely from steroid pretreatment and threshold variation; results remained robust after excluding high-risk studies per QUADAS-2.0
Conclusions:
CRP is the most sensitive and platelets the most specific marker for GCA, with normal ESR + CRP effectively ruling out disease and triple elevation markedly increasing diagnostic likelihood.
Disclaimer: Abstracts were not reviewed by Neurology® and do not reflect the views of Neurology® editors or staff.