What are the key clinical features that suggest a diagnosis of Giant Cell Arteritis in a patient presenting with headache?

Headache is a common manifestation of Giant Cell Arteritis (GCA) ², ((Osiowski et al., 2025)). GCA is a medical emergency, particularly due to the risk of sudden irreversible sight loss ¹. It typically affects individuals aged 40 years and older ¹.

Key clinical features suggesting GCA in a patient presenting with headache include the headache itself, which is often accompanied by other symptoms ². These associated symptoms can include visual disturbances such as new visual loss (transient or permanent) or double vision ¹,². Jaw claudication, which is pain in the jaw when chewing, is another characteristic symptom ¹,². Other non-visual symptoms, such as a return of headache or jaw claudication, should prompt medical attention ¹.

Supporting laboratory findings, though not definitive for diagnosis, often include an elevated C-reactive protein (CRP) level and an erythrocyte sedimentation rate (ESR) typically greater than 50 mm/hour ¹. However, the ESR may be normal at presentation ¹. Normochromic normocytic anaemia and an elevated platelet count are also common blood test abnormalities ¹. A rapid response of symptoms to corticosteroids is usually observed in GCA; a poor response may suggest an alternative diagnosis ¹.