Abstract
Renal artery aneurysms (RAAs) are rare and primarily affect elderly patients. They can be caused by connective tissue diseases, arteritis, or infection. However, most RAAs are caused by gradual degenerative changes that weaken the elastic laminae of the arteries. The condition progresses slowly, and it takes time to develop to a size that can cause symptoms. We report a case of RAA in an elderly woman who required surgical treatment. The aneurysm progressed from the normal arterial diameter to 30×25 mm within 10 days after the onset of a urinary tract infection. The patient was successfully treated with aneurysm resection, renal artery bypass, and re-implantation of both renal veins. Rapidly growing renal artery aneurysm may occur after urinary tract infection, and renal vein re-implantation can be a useful option for renal artery aneurysm repair.