What is the role of platelet count in the diagnosis of giant cell arteritis (GCA) (temporal arteritis)?

Updated: Sep 03, 2020
  • Author: Mythili Seetharaman, MD; Chief Editor: Herbert S Diamond, MD  more...
  • Print
Answer

Platelet counts are mildly elevated in most patients. A platelet count greater than 400,000/µL, although not in itself diagnostic, is more helpful than an elevated ESR for ruling in GCA. [89] Conversely, a normal platelet count is more accurate than a normal ESR for ruling out GCA. [90] Additionally, in the largest population-based GCA study to date in the United States (3001 patients), the combination of elevated platelet counts and CRP levels greater than 2.45 mg/dL was associated with a positive temporal artery biopsy, while ESR results were not as specific a predictor. [89]


Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!