Nephrogenic Systemic Fibrosis Risk 77 Times Higher Among Dialysis Patients

[RightSide]

Nephrogenic Systemic Fibrosis Risk 77 Times Higher Among Dialysis Patients

Published: November 17th, 2009

The results of a new study into side effects of gadolinium MRI contrast agents indicates that patients undergoing dialysis are at 77 fold higher risk of contracting nephrogenic systemic fibrosis (NSF), and kidney transplant patients face a 69 fold higher risk of developing the rare and potentially life-threatening condition, which is associated with a hardening and thickening of the skin and other tissue throughout the body.

Gadolinium-based contrasting agents (GBCA) are often given to patients undergoing magnetic resonance imaging scans (MRIs) to improve the outcome of the scans, allowing doctors to distinguish blood vessels from nearby tissue. The MRI contrast agents were prescribed to more than 9.5 million patients in the United States in 2008.

The contrast agents already carry a “black box” warning about the risk of NSF, also sometimes referred to as nephrogenic fibrosing dermopathy (NFD), among patients with kidney problems. The study, published in the latest issue of the Archives of Dermatology, was designed to estimate the risk of developing this debilitating condition among this already defined at-risk population.

Nephrogenic systemic fibrosis is a progressive disorder that severely restricts movement and may result in death. It is associated with the formation of excessive scar tissue in the skin and connective tissue of other internal organs. This results in thick, coarse and hard skin, which make it difficult to move the arms, hands, legs or feet. There is no known cure or effective treatment for the painful and debilitating condition.

Researchers looked at 94,917 patients exposed to gadolinium contrast agents at the Mayo Clinic between January 1, 1999 and December 31, 2006, finding that 1% of patients undergoing hemodialysis, and 0.8% of patients who have undergone renal transplant are at risk of developing NSF, compared to 0% of patients who underwent liver transplants. This equates to a 77 fold and 69 fold higher risk respectively, leading researchers to conclude that the increased risk is thought to be associated with poor clearance of most of the contrast agents.

The study’s authors said in their conclusions that the medical community should consider new guidelines for the use of GBCAs that would minimize the risk to patients while keeping them as effective tools for gathering diagnostic information.

“The GBCAs add important diagnostic information to patient examinations, and one possibility to be considered is whether guidelines similar to those that form the basis of the ALARA (as low as reasonably achievable) principle with regard to limitation of radiation exposure should be implemented for GBCA administration for all patients,” the study’s authors concluded.

An FDA advisory committee is scheduled to meet next month to re-examine the NSF warnings for all gadolinium-based contrast agents and to determine whether some in particular should be contra-indicated for patients with moderate to severe kidney problems. Although all gadolinium contrast agents can cause NSF, most of the reported cases involve GE Healthcare’s Omniscan.

There are currently about 400 nephrogenic systemic fibrosis lawsuits pending in state and federal courts throughout the United States against the makers of MRI contrast agents. In addition to GE Healthcare, cases are also pending against Bayer Healthcare (maker of Magnevist), Bracco Diagnostics (maker of MultiHance and ProHance) and Covidien (maker of Optimark). The gadolinium lawsuits all allege that the manufacturers did not adequately research their product and failed to warn consumers about the risk of developing the debilitating and life-threatening condition.

http://tinyurl.com/ycf8o6a

[Jean]

More good news!!!!!!!

[RightSide]

UPDATE 2-US FDA sees varying risk from MRI agents
Tue Nov 17, 2009 5:58pm EST

By Lisa Richwine

WASHINGTON, Nov 17 (Reuters) - Some contrast agents used with magnetic resonance imaging scans appear to carry a higher risk of a potentially fatal skin disease than others, U.S. drug reviewers said in documents released on Tuesday.

The Food and Drug Administration said a staff review found the highest risk of the skin disease, nephrogenic systemic fibrosis (NSF), was associated with GE Healthcare's (GE.N: Quote, Profile, Research, Stock Buzz) Omniscan, Bayer AG's (BAYGn.DE: Quote, Profile, Research, Stock Buzz) Magnevist and Covidien's (COV.N: Quote, Profile, Research, Stock Buzz) Optimark.

The lowest risk was associated with Prohance and Multihance, made by Bracco Diagnostics, the agency said, adding "the data do not appear to rule out an NSF risk for each of the agents."

The agency said the staff review that found variations among the drugs had limitations and it would take the issue to a panel of outside experts that meets in December.

The products, used to help make MRI scans easier to read, have been given to millions of patients. They are members of a family known as gadolinium-based imaging agents. The FDA announced in 2007 it was requiring a strong "black box" warning on all of the drugs to alert physicians that patients with certain kidney and liver conditions were at risk for for NSF.

Staff in the FDA's drug safety unit said the magnitude of the risk "does not compel removal of specific (imaging agents) from the U.S. market" but recommended that the drug labels note the varying levels of risks with each product.

NSF triggers thickening of the skin, organs and other tissues that makes it difficult to move and can lead to broken bones, although the exact cause is unclear. There is no effective treatment.

FDA reviewers said the extent of risk from any of the agents was unknown. One study of Omniscan estimated the chances of developing NSF was 4 percent among patients with severe kidney impairment.

Covidien spokeswoman Erica Abbett said the company had voluntarily modified the Optimark label to say it should not be used in patients with severe kidney impairment, which affects less than 0.5 percent of the U.S. population.

The company decided "it was prudent to act now, rather than wait for a causal link... to be established" between the imaging drugs and NSF, Abbett said.