Fig. 1. Ultrasound demonstrates normal right renal arterial flow.		Fig. 2. Aortogram demonstrates a normal left renal artery and only the proximal portion of the right renal artery is seen (arrow).
Case Reference No. CC-997-07 The patient is a 12-year-old male who presented with hypertension of 220/110 mm Hg. His blood pressure had been normal 1 year earlier. The patient and family could not recall any history of trauma. The initial diagnostic work-up included normal serum laboratory studies and an abdominal ultrasound which demonstrated a 9.3-cm left kidney with evidence of medullary nephrocalcinosis and increased resistive indices of 0.83, and a 10.3-cm right kidney with normal flow and resistive indices (Fig. 1). There was no evidence of a mass or hydronephrosis. A chest radiograph demonstrated cardiomegaly with left ventricular hypertrophy and a tortuous aorta. A nuclear medicine renogram demonstrated right:left function of 60:40. The left kidney was believed to be the cause of the hypertension. We were asked to perform a renal arteriogram and obtain renal vein renin samples. Aortography and selective catheterization of each renal artery was performed. The left renal artery was normal. The right renal artery was proximally occluded; multiple adrenal collateral vessels emerged from the stump. This occlusion could not be crossed with an 0.018-inch Glidewire (Figs. 2­4). Selective catheterization of several lumbar vessels demonstrated multiple retroperitoneal collateral vessels with reconstitution of the segmental intrarenal arteries (Fig. 5). The inferior vena cavogram demonstrated a normal left renal vein. The right renal vein was occluded. Multiple collateral veins draining into the retroperitoneum, mainly through the hemiazygos system, and also into the inferior vena cava (IVC) were seen (Figs. 6, 7). The mid IVC was narrowed with anteromedial deviation at the expected location of the right renal vein. Renin sampling was obtained from the left renal vein, right renal vein caval collaterals, and the infra- and suprarenal IVC. All renin levels proved markedly elevated without evidence of lateralization. A follow-up MR study demonstrated a soft-tissue mass at the area of the right renal artery and vein occlusion, and the diagnosis at that time was a tumor of neuroendocrine origin. At surgery a 3-cm thrombosed right renal artery aneurysm was found without evidence of a mass. Fibromuscular dysplasia was diagnosed at pathology. The right kidney was autotransplanted into the right iliac fossa. Unilateral, left-sided medullary nephrocalcinosis was present, presumably because the right kidney was protected from the renovascular hypertension.		Fig. 3. Selective left renal arteriogram with normal arborization. Fig. 4. Selective right renal arteriogram with mid and distal occlusion and adrenal collateral vessels. Fig. 5. Selective lumbar catheterization demonstrates capsular and ureteral collateral vessels and notching of the ureter.
Fig. 6. Frontal view. Inferior vena cavogram shows no evidence of a main right renal vein. Retrograde filling of multiple retroperitoneal collateral veins (arrow) (mainly the hemiazygos system) is seen, along with narrowing and medial deviation of the IVC (arrowhead), at the expected location of the right renal vein.		Fig. 7. Lateral view. Inferior vena cavogram demonstrates the retroperitoneal collateral vessels (arrow) and narrowing, with anterior deviation of the IVC (arrowhead).
Related Cases: Case 497_09 -- Renal artery stenosis in a child resistant to PTA