What is It?
Nephrogenic systemic fibrosis is a rare disease that can cause debilitating symptoms or even result in fatality. This condition causes thickening of the skin and formation of excess fibrous tissue on almost all of the organs in the human body. Fibrous tissue can also develop on the joints, resulting in a loss of motion within as little as a few weeks. Signs and symptoms of this condition include reddened areas of the skin, joint stiffness, burning skin, itching skin, pain, yellow discoloration of the eyes, muscle weakness and restricted motion.
While doctors do not know the exact cause of this condition, scientists suspect that gadolinium-based contrast agents (GBCAs) play a role in the development of nephrogenic systemic fibrosis. Radiologists use GBCAs to enhance appearance of blood vessels and other body structures on magnetic resonance imaging (MRI) films. Most MRI contrast agents contain gadolinium. In people who have normal kidney function, the use of GBCAs is considered safe because the kidneys expel the gadolinium from the system very quickly. In those with kidney disease or acute kidney injury, the elimination of the gadolinium may be delayed substantially, giving the chemical the opportunity to cause damage.
Although scientists need to perform more research to determine if GBCAs cause this condition, some evidence exists that does point to the use of GBCAs as a risk factor for NSF. The first documented case of this condition did not occur until 1997; 1997 is when radiographers started using GBCAs. In recent years, the use of magnetic resonance angiography (MRA) increased dramatically. MRA uses two to three times the dosage of GBCAs as other MRI procedures.
While there is no cure for NSF, improving kidney function seems to slow down the progression of the condition. Several drugs have shown promise in delaying the progression of NSF. Some doctors prescribe oral steroids for this condition, but people who have diabetes should use these drugs with caution. Oral steroids increase the risk for high blood sugar in some patients. Dovonex may cause some improvement in the disease, but the results as of December 2010 were anecdotal and not well-documented. Some researchers have experiment with the use of Cytoxan, extracorporeal photopheresis and plasmapheresis, but more research is needed to determine if these treatments work.
Since the exact cause of NSF is unknown, it is not possible to prevent the condition in 100 percent of patients. Medical professionals, however, can identify those with the greatest risk of NSF and take steps to prevent the condition. In those with existing kidney disease, GBCAs should only be used when the benefits of using a gadolinium-based agent outweigh the risk of developing NSF. One way to determine the renal function of a patient about to undergo an MRI procedure is to check his BUN and creatinine levels. The kidney filters BUN and creatinine out of the body in the urine. If blood levels of these substances are elevated, it could indicate impaired kidney function, making it necessary to avoid the use of GBCAs.
The International Center for Nephrogenic Systemic Fibrosis Research: What is NSF?
National Kidney Foundation: NSF – Reducing Risk in Patients With Acute Kidney Injury and Chronic Kidney Disease