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What nephrologists need to know about gadolinium

Abstract

Gadolinium chelates are commonly used to improve tissue contrast in MRI. Until recently the use of gadolinium was thought to be risk-free compared with alternative contrast agents. Recent studies, however, have raised serious concerns regarding the safety of gadolinium chelates. Although safe in patients with normal kidney function, administration of these agents in people with renal dysfunction can result in up to three clinical problems that the nephrologist should be familiar with. The first is nephrogenic systemic fibrosis (NSF), which was initially observed in 1997. Although manifesting primarily in skin, NSF can also cause systemic fibrosis, leading to disabling contractures and even death. Gadodiamide is the agent that has been most frequently associated with NSF, but other chelates might also pose a risk. The second clinical problem is that gadolinium chelates cause acute kidney injury, especially at high doses required for angiography. The third problem is that several laboratory artifacts are associated with gadolinium administration, with pseudohypocalcemia being the most important. The risk of a patient experiencing all three of these complications increases as renal function declines. In light of these problems, nephrologists need to re-evaluate the risks and benefits of gadolinium administration in patients with chronic kidney disease stage 3 or greater, as well as in those with acute kidney injury.

Key Points

  • Originally thought to be safe contrast agents, gadolinium chelates have recently been shown to be associated with the development of nephrogenic systemic fibrosis (NSF) in patients with impaired renal function

  • NSF, previously known as nephrogenic fibrosing dermopathy, occurs only in patients with kidney dysfunction, is characterized by waxy thickening of the skin of the extremities and torso, and commonly leads to joint contractures and immobility

  • The proposed, but not yet proven, etiology of NSF is tissue deposition of free gadolinium that is liberated from chelates, secondary to prolonged gadolinium clearance time due to impaired renal function

  • Treatments for NSF have only been tested informally; the condition has been shown to improve in response to recovery of kidney function

  • Several authorities have issued recommendations for use of gadolinium chelates; most advise caution when considering use of these agents in patients with renal dysfunction

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Charles P Vega, University of California, Irvine, CA, is the author of and is solely responsible for the content of the learning objectives, questions and answers of the Medscape-accredited continuing medical education activity associated with this article.

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Penfield, J., Reilly, R. What nephrologists need to know about gadolinium. Nat Rev Nephrol 3, 654–668 (2007). https://doi.org/10.1038/ncpneph0660

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