Cranial versus Extracranial Involvement in Giant Cell Arteritis: 15 Years Retrospective Cohort Analysis

Giant cell arteritis (GCA) is a medium-large systemic vasculitis presenting primarily in patients over 50 years. It usually involves carotid artery branches, especially the temporary artery; nevertheless, it can affect the arterial wall of other large and medium arteries. 1 Cranial manifestations are the most frequent and usually define the study. 2 Extracranial involvement, otherwise frequent, can modify clinical and diagnostic features of the disease and may need higher levels of suspicion and other diagnostic strategies to address territories involved. 3 Reports regarding extracranial involvement in GCA vary depending on the diagnostic method used, ranging from 3% to 92%. Using angiography, the prevalence ranges from 20% to 67%; on the other hand, positron emission tomography with 18F-fluorodeoxyglucose (FDG-PET) shows 83% and 92%. 3,4 Up to 77% of these patients are asymptomatic and present isolated extracranial involvement. 5 The most frequently affected extracranial sites are the carotid, subclavian, axillary, and thoracic aorta, which can be complicated with dissection and aneurysms of the affected arteries. 4 There are some comparative series between cranial involvement patients and those with extracranial involvement; nevertheless, those do not include Latin American population-based cohorts, including clinical, imaging, and biopsy features. 6–8 In a 15-year retrospective cohort study including the