Surveillance of a Transplant Kidney Harboring a Stable Renal Artery Aneurysm: A Case Report

Renal artery aneurysms (RAAs) may occur in patients with transplanted kidneys, either through de novo development or as a preexisting feature of the donor kidney. How this vascular condition progresses in patients on immunosuppressive therapy after transplantation is poorly understood, and to our knowledge, consensus guidelines for treating transplant patients with RAA have not been developed. We present the case of a kidney allograft recipient on triple immunosuppressive therapy in whom postoperative imaging revealed a 13-mm renal artery aneurysm in the renal hilum not amenable to endovascular intervention. We review systemic influences on aneurysm formation and how matrix metalloproteinases may interact with immunosuppressive medications. Surveillance imaging over 5 years has shown a stable aneurysm, and the patient has maintained stable renal function with adequate creatinine levels and no adverse symptoms.