Gadolinium and nephrogenic systemic fibrosis: association or causation.

With widespread availability of magnetic resonance imaging (MRI), it has become standard practice for patients with severe renal impairment or previous severe reactions to iodine-containing contrast media to receive gadolinium-based MRI contrast agents instead of traditional radiographic contrast agents, particularly for magnetic resonance angiography. However, there is growing concern about the use of gadolinium contrast agents in the presence of severe renal insufficiency, because of increasing reports of nephrogenic fibrosing dermopathy (NFD)/nephrogenic systemic fibrosis (NSF), associated with the exposure to certain gadolinium-containing contrast agents. In this review we explore the causal link between gadolinium exposure and NSF, using an established system of epidemiological criteria proposed by Bradford Hill. Though the current evidence makes gadolinium a strong suspect as an aetiologic agent for NSF in the presence of severe renal failure, the die is not cast yet. At this stage there needs to be cautious approach to the use of gadolinium-containing contrast agents in the presence of severe renal failure (glomerular filtration rate <30 mL/min per 1.73 m(2)).