What are Nephrogenic Systemic Fibrosis and Contrast Induced Nephropathy?

Nephrogenic Systemic Fibrosis (NSF) (also known as Nephrogenic Fibrosing Dermopathy)

This condition is rare and, so far, has occurred only in people with severe kidney disease. No cases were reported prior to 1997. It causes swelling and tightening of the skin of the extremities and less often the trunk. It develops over days to weeks and may reduce movement of the joints. It can also cause damage to internal organs in rare cases. About 5% of people with the most severe level of kidney function reduction will get NSF after a gadolinium injection and less than 5% of these people (or 3 in every 10,000 people with severely reduced kidney function)) will die of it. NSF is much more common with some gadolinium contrast agents than others and is more common after multiple doses of gadolinium based contrast media.

Improvements in kidney function, through kidney transplant or other measures, have been shown in some cases to result in remission of NSF but this is not always the case. Certain medical conditions and procedures can increase the risk of NSF in patients with kidney function impairment and these include: vascular procedures (e.g. dialysis fistula revision, angioplasty), those with thrombotic tendency (for example, deep venous thrombosis), and those with recent onset of acute kidney failure (including transplant failure) in the weeks before developing NSF.

The risk of contracting NSF should be seen in the context of how rare it is. On 8 June 2006 the U.S. Food and Drug Administration (FDA) issued a public health advisory indicating that 25 patients who had received a gadolinium compound (Omniscan (gadodiamide)) had developed NSF. All of these patients had kidney failure and of the 25 cases (reported by the Danish Medicines Agency) 20 of the cases were reported in Denmark and 5 in Austria. An updated warning from the FDA was issued in May 2007 and confirmed cases in association with other gadolinium compounds (Omniscan, Magnevist (gadopentetate dimeglumine) and Optimark (gadoversetamide)).

Patients at greatest risk were again identified as those with acute or chronic renal impairment. The risk is increased if a patient has multiple doses of gadolinium compounds.

It appears that the contrast agents Gadovist (Bayer Schering Pharma) Dotarem (Guerbet) and Prohance are associated with a much lower chance of NSF even in patients with poor kidney function, and so these are often used when it is felt that gadolinium administration is essential for diagnosis in patients with very poor kidney function. An example of this might be in a patient with cancer and neurological symptoms who needs a brain MRI to search for spread of the tumour, but who also has very poor kidney function. The use of gadolinium contrast in this situation makes it much easier in many cases for the radiologist to see evidence of early (metastatic) disease, i.e. where the cancer has spread from the original tumour to another part of the body. One of the agents listed above, that are known to be much lower risk in terms of causing NSF, may be used in this situation after explaining the risk versus benefit to the patient.