An Unusual Case of Renal-Limited Giant Cell Arteritis.

It is widely accepted that giant cell arteritis (GCA) is a disease of the carotid branches. There are very few cases describing disseminated disease or visceral involvement. Isolated renal GCA presenting with renal failure is even more unusual. A 76-year-old male with no known medical history presented to the emergency department with three weeks of weakness, swelling, oliguria, and shortness of breath. He was started on hemodialysis for renal failure. After microscopic urinalysis revealed red blood cell casts, a kidney biopsy was performed and showed granulomatous arteritis suggestive of GCA in the renal vasculature. Despite an aggressive corticosteroid regimen, the patient remained dependent on hemodialysis until his death from an unrelated cause. The leading diagnosis throughout most of the workup in this case was end-stage renal disease in the setting of previously undiagnosed chronic kidney disease. A thorough workup revealed a far less common disease process, which significantly altered the patient's treatment course and highlighted the importance of maintaining a broad differential.