Gadolinium and its water-soluble paramagnetic complexes can improve the magnetic resonance imaging signal of human body in medical treatment,
According to statistics, the incidence of toxic and side effects of gadolinium contrast agent is 2%-4%.
Recently, the US Food and Drug Administration (FDA) issued a public health warning about gadolinium-containing contrast agents. According to this recommendation, FDA is evaluating important safety information about whether gadolinium-containing contrast agents are related to nephrogenic systemic fibrosis/nephrogenic fibromatosis (NSF/NFD, which usually occurs in renal failure). The monitoring report found that there may be a relationship between NSF/NFD and the high-dose gadolinium-containing contrast agent used in magnetic resonance angiography (MRA). MRA uses magnetic resonance imaging to photograph blood vessels. In MRA examination, a contrast agent called gadolinium is injected into the vein of the patient so that blood vessels can be distinguished from adjacent tissues. The FDA was informed that after MRA examination with Omniscan (a gadolinium-containing contrast agent), 25 patients with renal failure reported NSF/NFD cases. At present, FDA is actively studying whether exposure to gadolinium-containing contrast agent in M-RA examination is related to the occurrence of NSF/NFD disease. During the FDA investigation, the following suggestions were made to medical staff and patients: gadolinium-containing contrast agents, especially high-dose gadolinium-containing contrast agents, should be used only when patients with severe renal insufficiency are determined to have to use them. Patients with severe renal insufficiency refer to patients who currently need dialysis or whose glomerular filtration rate (GFR) is ≤15cc/min. For patients with severe renal insufficiency, dialysis can be considered in time after MRA examination with gadolinium-containing contrast agent. Although there is no data to prove that dialysis can prevent or treat NSF/NFD in patients with renal dysfunction, the average clearance rate of gadolinium after the first to third hemodialysis is 78%, 96% and 99% respectively. The FDA has approved five gadolinium-containing contrast agents for magnetic resonance imaging (MRI). The trade names of these five gadolinium-containing contrast agents are Omniscan, OptiMARK, Magnevist, ProHance and MultiHance. None of these drugs have been approved by FDA for MRA. The dose of gadolinium-containing contrast agent used in MRA examination is usually higher than the approved dose of MRI examination (up to 3 times). NSF/NFD was first discovered by scientists in 1997, and its pathogenesis is still unclear. NSF/NFD seems to occur in renal failure patients with high body fluid acid levels, which is a common acidosis state known in renal failure patients. The skin of NSF/NFD patients is tight and hard, so it is difficult to bend the joints. NSF/NFD can also lead to fibrosis or scarring of body organs, which will lead to the loss of function, failure to work normally and death of human organs. At present, about 200 cases of NSF/NFD have been found all over the world. Danish medical authorities reported 25 cases of NSF/NFD on May 29th, 2006. Among them, 20 cases occurred in Denmark and 5 cases occurred in Austria. The patient developed NSF/NFD within 3 months (2 weeks to 3 months) after receiving gadolinium-containing contrast agent. FDA is not sure that the use of gadolinium-containing contrast agent in MRA examination will lead to NSF/NFD in patients with renal failure. The FDA is collecting supplementary information about NSF/NFD and investigating whether other patients receiving gadolinium-containing contrast media also have NSF/NFD. (Reprinted from China Medical News)