Giant Renal Artery Aneurysm With Hydronephrosis and Severe Atrophy of the Renal Parenchyma: Case Report and Literature Review.

Background: It is known that renal artery aneurysms may lead to hydronephrosis, but utter shrinking of the renal parenchyma due to a giant renal artery aneurysm has not yet been reported. This report is of an 88-year-old woman with resistant hypertension, hydronephrosis, and renal atrophy due to a giant saccular aneurysm of the left renal artery. Case Report: The patient presented with 2 weeks of worsening low back pain on the left side and resistant hypertension. The discovery of a left flank mass on physical examination, lead to the ultrasound detection of a para-aortic mass and a cyst-like partially septate structure replacing the left kidney. Thereafter, a contrast-enhanced computed tomography scan revealed a giant saccular aneurysm of the left renal artery causing severe hydronephrosis with severe parenchymal thinning. The extreme parenchymal atrophy of the left kidney made it an unlikely culprit of resistant hypertension, therefore the interventional radiologist considered that an endovascular attempt to re-establish the patency of the left renal artery would have scarcely produced any benefit. Given the advanced age of the patient, the vascular surgeon considered that risk of a nephrectomy outweighed the benefit, in agreement with the patient's unwillingness to accept an invasive intervention. Therefore, she was discharged with blood pressure lowering and pain relief medication and was thereafter lost to follow-up. Conclusion: To our knowledge, this is the most severe kidney parenchymal shrinking in association with a renal artery aneurysm reported in the literature.