MedPix Medical Image Database COW - Case of the Week Case Contributor: Thomas C Alewine Affiliation: National Capital Consortium

MedPix No: History Pt Demographics: Age = 46 y.o. Gender = status post living related donor kidney transplant to the left iliac fossa in February 2001 who had progressive increased creatinine, worsening hypertension and recent renal ultrasound demonstrating high velocities at the anastomosis as well as increasedresistive index in the intrarenal arteries. Patient is not a candidate for magnetic resonance angiography due to the aortic valve replacement and has been on chronic Coumadin. The patient is referred for renal arteriogram and possible angioplasty. Downloaded by (-1)

MedPix No: EXAM & LABS noncontributory

Renal transplant angiogram proximal renal artery stenosis Downloaded by (-1)

Balloon placement/inflation proximal renal artery stenosis angioplasty Downloaded by (-1)

post 4-20 angioplasty post renal artery stenosis angioplasty Downloaded by (-1)

FINDINGS Contrast angiography with dilute contrast demonstrates a high-grade anastomotic stenosis at the origin of the renal artery extending for approximately 1cm. The renal transplant artery has a relatively acuteupward course from its takeoff from the external iliac artery. There is also eccentric narrowing of the external iliac artery immediately adjacent to therenal transplant origin. At angioplasty there is easy dilation of the balloon with an elastic character to the stenosis. Images following angioplasty demonstrate a mildlyimproved lumen with residual stenosis of approximately 50%. Pressure measurements after angioplasty demonstrate pressure of 144/80 in the renalartery and 176/86 in the external iliac artery, giving a gradient of 32mmHg.

DIFFERENTIAL DIAGNOSIS What is your Differential Diagnosis? Transplant Renal Artery Stenosis

Diagnosis: Transplant Renal Artery Stenosis seen on angiogram Dx Confirmed by:

DISCUSSION There is mild to moderate improvement in the high-grade stenosis after angioplasty to 4mm; however, the stenosis is elastic with a significant extrinsic component suggested. The residual gradient suggests that this is still hemodynamically significant. Options for treatment would include transplant artery anastomotic revision vs. stent placement. The latter has a lower patency in relatively small sized renal arteries.