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NEPHROGENIC SYSTEMIC FIBROSIS ASSOCIATED WITH GADOLINIUM‐CONTAINING CONTRAST MEDIA ADMINISTRATION IN PATIENTS WITH REDUCED GLOMERULAR FILTRATION RATE

To the Editor: We write to highlight the recently described association between gadolinium-containing contrast agents and nephrogenic systemic fibrosis (NSF, previously also known as nephrogenic fibrosing dermopathy). Magnetic resonance imaging (MRI) frequently requires the administration of gadolinium as a contrast agent. Gadolinium-containing contrast agents are occasionally used as an alternative to iodine-based angiographic contrast media in the setting of iodine allergy or significant renal impairment. Nephrogenic systemic fibrosis is a rare condition observed in patients with kidney impairment who are generally close to (eGFR < 15 mL/min) or requiring dialysis, and in patients with functioning kidney transplants. The precise incidence of this serious disease requires further studies, but nearly 200 cases have been reported worldwide. The typical presentation is well-defined, erythematous, indurated plaques on the limbs and trunk, and the course is typically progressive, with joint contractures, physical disability and even death. Internal organ fibrosis also occurs, involving heart, lung, liver, skeletal muscle and meninges. Short of improving renal function by transplantation, there is currently no established treatment for NSF, although a number of therapies have been used with varying success. Although the cause of NSF remains unclear, reports of the association with renal impairment and gadolinium infusion are published. Further, it has been considered by the United States Food and Drug Administration, which has issued a public health advisory recommending gadoliniumcontaining contrast agents be used only if clearly necessary in patients with advanced kidney failure and that prompt dialysis is instituted in patients with advanced kidney failure who receive gadolinium-containing contrast agents. Austin Health has reassessed its practice with regards to gadolinium-containing contrast agents. The standard pre-MRI questionnaire now acknowledges the presence of kidney impairment or kidney transplantation or the requirement of dialysis in the standard pre-MRI questionnaire, while restricting the use of gadolinium in patients with kidney impairment to strong clinical indications, which outweigh the risk of NSF. This risk assessment is difficult because the precise incidence of NSF is unknown. The authors have introduced this conservative approach despite the fact that we are not aware of any cases of NSF notwithstanding 97 dialysis patients receiving 146 doses of gadolinium-containing contrast agents at our institution. In conclusion, although a causal link between gadolinium and NSF has not yet been firmly established, we wish to urge caution in the usage of gadolinium in patients with impaired kidney function and consider that further studies should be supported in this area.