Abstract
Vascular obstructive causes must be considered in chronic renal failure with no obvious cause. We present the case of a 74-year-old woman with smoldering renal failure who undergoes a renal biopsy that did not undercover a cause. As her symptoms persisted and renal function worsened, her nephrologist proposed magnetic resonance angiography with gadolinium and prophylactic initiation of hemodialysis. Imaging uncovered an occlusive aortic mass, which was removed surgically with improvement in renal function. The case discusses the nature of the mass and the need to weigh the risks and benefits of MR imaging with gadolinium and initiation of hemodialysis against the risk of nephrogenic systemic fibrosis.