A Rare Case of Extracranial Giant Cell Arteritis in a Patient With Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is an autoimmune disease that affects multiple organs, and its coexistence with Giant Cell Arteritis (GCA) is extremely rare. We present, to our knowledge, the first reported case of a 56-year-old woman with SLE and extracranial GCA who presented with chest pain as the cardinal symptom. The diagnosis was subsequently confirmed by imaging studies, ruling out Takayasu arteritis and SLE-related vasculitis. She required treatment with glucocorticoids and tocilizumab, showing a satisfactory evolution. Accurate diagnosis was key to preventing serious vascular complications and achieving favorable clinical recovery.