Snapshot A 65-year-old woman presents to the emergency department due to a severe headache and visual impairment in the right eye. Her symptoms are associated with pain with chewing and proximal muscle morning stiffness. On physical exam, she has decreased visual acuity of the right eye, scalp tenderness on the right, and an absent pulse in the right temporal area. Laboratory testing is significant for an elevated erythrocyte sedimentation rate. She is admitted and immediately started on systemic glucocorticoids. Introduction Clinical definition a chronic large- and medium-sized vessel vasculitis that typically involves the temporal artery cranial arteries Epidemiology incidence most common systemic vasculitis affecting patients ≥ 50 years of age demographic woman > men Etiology presumed to be autoimmune Pathogenesis T-cells and monocytes are recruited to the vessel wall and result in an inflammatory response Associated conditions polymyalgia rheumatica Prognosis relapses can occur in 20-50% of patients Presentation Symptoms temporal headache jaw claudication amaurosis fugax symptoms of polymyalgia rheumatica (PMR) morning stiffness Physical exam scalp tenderness palpation of the temporal area may demonstrate absent pulse knot-like swelling vision loss findings of PMR distal extremity swelling Imaging Color-coded duplex ultrasound indication to assess the temporal arteries and extracranial vessels Studies Labs ↑ erythematous sedimentation rate ↑ C-reactive protein Temporal artery biopsy confirms the diagnosis Differential Migraine distinguishing factors may be accompanied by an aura, photophobia, and phonophobia Takayasu arteritis distinguishing factors typically affects young and Asian women Treatment Management approach high-dose systemic glucocorticoids should be promptly administered even before the diagnosis is established temporal artery biopsy confirms the diagnosis Medical corticosteroids indication standard initial treatment for patients suspected of having temporal arteritis Complications Blindness