Nephrogenic Systemic Fibrosis (NSF) is a rare degenerative disease that affects patients with serious kidney problems. It causes a buildup of scar tissue -- fibrosis -- on the skin and on several vital internal organs, including the heart, lungs and diaphragm. Its main symptom is the sudden appearance of skin lesions on the arms, legs, hands and feet, sometimes accompanied by swelling, pain and blisters. These lesions are painful and unsightly, looking a little like the skin of an orange -- but more importantly, they can be crippling. Over time, the hardened skin can prevent patients from bending joints, robbing them of the ability to walk and perform simple tasks. Patients may be bound to a wheelchair within a few weeks. In addition, scar tissue can build up so far on internal organs that it interferes with their functions, eventually causing death.
Scientists have strongly associated NSF with the use of a chemical called gadolinium -- a dye injected to make blood vessels easier to see in magnetic resonance imaging and magnetic resonance angiography (MRI/MRA) tests. Studies have found that more than 95% of American NSF patients have been directly exposed to gadolinium. In response, the U.S. Food and Drug Administration has already ordered a "black box" warning on the label of the dye, and research is underway to confirm the connection. Preventive Measures
Unfortunately, the best treatment for NSF is still prevention. The FDA has issued guidelines three times since June of 2006, each strongly suggesting that doctors avoid using gadolinium in patients with moderate to end-stage kidney disease. More specifically, the agency has strongly suggested that doctors avoid using gadolinium for MRIs or MRAs in patients with chronic or severe renal insufficiency (kidney failure), with a glomerular filtration rate at or below 30 milliliters a minute; or in patients with any level of kidney dysfunction caused by liver problems. Doctors are not prohibited from using the dye with these patients, but are strongly advised against it unless they truly need it to make a diagnosis. Even then, they are asked to make sure they do not use more than the recommended dosage. Also, the FDA has asked doctors to consider sending these patients for dialysis as soon as possible after the MRI.
Experimental Treatments
Currently, there is no consistently successful treatment for NSF. In fact, the disease is so new -- it was first identified in 1997 -- that doctors are still investigating several treatments to see which give patients the best long-term relief. Treatments that have helped some patients include:
* Improving kidney function is the treatment with the most consistent good results. This can mean medical treatment (including dialysis), a kidney transplant or both. While improved kidney function has actually reversed the course of NSF in some cases, it has had no effect in other cases.
* Oral steroids are pills that have improved the skin problems of some patients. They do not work for everyone, and may cause calcium deficiency, high blood sugar and ulcers, making them inappropriate for many people with some other health problems.
* Skin creams and ointments, such as vitamin D3 and forms of cortisone, have helped some people fight their skin symptoms.
* Physical therapy, especially swimming, and deep massage have helped some patients slow down NSF's effect on their joints.
* A few patients have improved by using the drugs thalidomide, pentoxifylline and cytoxin, but these have not had widespread success. Similarly, two types of blood treatments -- plasmapheresis and extracorporeal photopheresis -- and ultraviolet light therapy have been helpful for one or two patients. But in all of these cases, more research is needed.
In addition, a recent study from Wake Forest University Baptist Medical Center suggests that NSF could be stopped before it starts if doctors are able to administer drugs that inhibit a bodily enzyme called transglutaminase-2 (TG2). These researchers found high levels of TG2 in patients with NSF, which suggests that the enzyme helps activate the disease. If that's true, doctors may someday be able to prevent NSF by prescribing existing drugs that inhibit TG2.
Nephrogenic systemic fibrosis is a deadly, incurable disease that can disable and eventually kill a patient, often a patient who is already weakened by kidney failure. It is also completely preventable -- if doctors work closely with patients and their loved ones to avoid using gadolinium in kidney patients. As of late December 2006, the FDA had identified 215 patients with NSF around the world; every single one whose medical history they could review had been exposed to gadolinium. If you or a loved one has developed NSF after being given a dye with gadolinium for an MRI or MRA, you deserve answers.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment