In this episode, we review giant cell arteritis (GCA), an autoimmune large-vessel vasculitis that most commonly affects the temporal arteries and can lead to devastating ischemic complications if not recognized early. We discuss the underlying inflammatory pathophysiology, major risk factors including advanced age and polymyalgia rheumatica, and the hallmark presentation of temporal headache, jaw claudication, scalp tenderness, and transient vision loss. The episode also covers key diagnostic findings such as elevated ESR and CRP, the classic "halo sign" on Doppler ultrasound, and why temporal artery biopsy remains the gold standard for diagnosis. Treatment focuses on the urgent initiation of high-dose glucocorticoids to prevent permanent vision loss and other vascular complications.

References

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