All are true about Giant cell aeritis except
**Giant Cell Arteritis Explanation**
**Core Concept**
Giant cell arteritis (GCA) is a large vessel vasculitis characterized by granulomatous inflammation of the aorta and its major branches, typically affecting individuals over the age of 50. The underlying pathophysiology involves an autoimmune response leading to the activation of immune cells, resulting in the release of pro-inflammatory cytokines.
**Why the Correct Answer is Right**
GCA predominantly affects the branches of the external carotid artery, particularly the temporal artery, leading to symptoms such as headache, jaw claudication, and visual disturbances. The inflammation in GCA involves the activation of T lymphocytes and macrophages, which release cytokines like IL-6 and TNF-alpha, contributing to the disease process. The granulomatous inflammation in GCA is characterized by the presence of multinucleated giant cells.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as GCA is indeed more common in individuals of Northern European descent.
**Option B:** This option is incorrect as the exact cause of GCA is still unknown, but it is believed to be related to an autoimmune response to an unknown antigen.
**Option C:** This option is incorrect as the most common symptoms of GCA include headache, scalp tenderness, jaw claudication, and visual disturbances, not just fever.
**Clinical Pearl / High-Yield Fact**
GCA is often associated with polymyalgia rheumatica (PMR), and a significant proportion of patients with PMR will eventually develop GCA. Clinicians should have a high index of suspicion for GCA in patients with PMR who present with visual disturbances or other symptoms of large vessel vasculitis.
**Correct Answer: D.**