Large vessel vasculitides, Polymyalgia rheumatica (classification, pathomechanism, symptoms, treatment)

1. Big picture

This topic has three exam-relevant diseases:

1. Giant cell arteritis (GCA) — elderly patient, new headache, jaw claudication, visual symptoms, high erythrocyte sedimentation rate (ESR)/C-reactive protein (CRP).
2. Takayasu arteritis (TAK) — young woman, aortic arch/branch inflammation, limb claudication, pulse or blood pressure asymmetry.
3. Polymyalgia rheumatica (PMR) — elderly patient, shoulder/hip girdle pain and morning stiffness, high ESR/CRP, dramatic response to low-dose glucocorticoids.

The emergency trap is GCA with visual symptoms: treat immediately with high-dose glucocorticoids; do not wait for biopsy or imaging.

Large-vessel vasculitis mainly affects the aorta and its major branches; GCA and TAK are the classical large-vessel vasculitides in modern classification systems. The 2021 ACR/Vasculitis Foundation guideline specifically addresses GCA and TAK as the main exemplars of large-vessel vasculitis. ([PubMed][1])

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