Cranial and extracranial manifestations of giant cell arteritis: a single-center observational study.

Introduction: Giant cell arteritis (GCA) presents two major phenotypes - cranial (cGCA) and extracranial (exGCA). exGCA may be overlooked. The study aimed to compare the clinical characteristics between cGCA and exGCA.

Methods: Electronic medical records of patients treated between January 2015 and July 2023 at the Department of Rheumatology were searched for the diagnosis of GCA. The clinical characteristics of patients with cGCA, exGCA, and overlapping GCA manifestations were compared.

Results: Out of 32 patients with GCA, 20 had cGCA, 7 had exGCA, and 5 had overlap manifestations. The groups did not differ significantly in demographics, clinical signs/symptoms, or laboratory test results. Importantly, the combined group of patients with exGCA and overlap GCA had a statistically significant delay in initiating treatment (median 12 weeks) compared to patients with cGCA (median 4 weeks; p = 0.008).

Conclusion: Our study confirmed the insidious nature of exGCA, which lacks distinctive clinical symptoms and consequently leads to delayed treatment.