A Case of a Giant Internal Iliac Aneurysm Leading to Acute Postrenal Renal Failure

Abstract

Internal iliac artery aneurysms are often asymptomatic and may be detected through urinary or neurological symptoms depending on their size and location. However, unilateral internal iliac artery aneurysms rarely cause acute postrenal failure, even if they lead to unilateral hydronephrosis. Here, we report the case of a 76-year-old male who presented to our hospital with complaints of urinary dysfunction. A computed tomography (CT) scan revealed a giant left-sided internal iliac artery aneurysm measuring 100 mm in diameter, compressing the bladder and resulting in bilateral hydronephrosis. The patient exhibited severe renal impairment, with a serum creatinine (Cr) level of 6.16 mg/dL, and was diagnosed with acute postrenal failure due to the left internal iliac artery aneurysm. Emergency endovascular intervention was performed, including distal embolization of the left internal iliac artery and stent-graft placement within the iliac artery. Postoperative renal function improved, with serum Cr decreasing to 1.46 mg/dL, and the patient was discharged on day 10. While endovascular treatment for internal iliac artery aneurysms effectively prevents rupture, it may not always restore renal function due to the potential persistence of the aneurysm. In this case, however, the reduction in aneurysmal pressure alleviated compression on the bladder and ureters, leading to improved renal function. This suggests that endovascular treatment of internal iliac artery aneurysms may be beneficial not only for rupture prevention but also for resolving aneurysm-induced postrenal failure.