One MRI please, hold the gadolinium

One of the recurring nephrology consults that I am asked to see in the hospital revolves around the use of contrast dye that is used in a variety of medical imaging studies. In both CT scans and MRI scans--a way of obtaining very nice images of the living body and crucial for a variety of diagnoses)--the use of contrast is often needed in order to get a high-quality image. Unfortunately, however, these contrast dyes can be toxic to the kidneys, particularly in people who already have some underlying kidney damage.

The hottest topic in this field is the use of gadolinium in MRI images, such as the one showed here giving a nice look at the kidneys and the renal arteries which supply them with blood. (The big long vessel running vertically on the image is the aorta; the two vessels coming off the aorta which lead to the kidneys are the left and right renal arteries). Gadolinium was once considered perfectly safe for the kidneys. In just the past year, however, there has been a growing concern that gadolinium, while not extremely toxic to the kidneys, can be responsible for a terrible skin condition called nephrogenic systemic fibrosis, or NSF. I won't go into details as to what NSF is, but suffice it to say, you don't want to get it: your skin experiences an extreme tightening, which can be so severe that it can cause muscle contractures and can event prevent walking. Not surprisingly, the decision has been made at most major hospitals to not give gadolinium to patients with end-stage kidney failure.

Not surprisingly, the legal community has been quick to respond to this news. In fact, when I google "nephrogenic systemic fibrosis", the first web sites to pop up are not in fact medical sites but rather lawfirms advertising free consultations for individuals who might be afflicted with NSF. Apparently there has been a big push to file lawsuits against the companies which manufacture the contrast agent, saying that the companies did not adequately determine the safety of their product before it was released into clinical practice. Gadolinium has been used for several decades now and it's only been recently that enough cases of NSF have occurred in order to determine the association between renal failure and NSF, and even now due to the rarity of the condition this is still considered somewhat controversial.