Contrast-induced nephropathy and nephrogenic systemic fibrosis: Minimizing the risk

Introduction: Contrast-enhanced cross-sectional imaging is essential to the urologist's practice. Traditionally, patients with impaired renal function could not be imaged with a computed tomography (CT) scan with contrast due to the risk of contrast-induced nephropathy (CIN). These patients could alternatively be imaged by magnetic resonance imaging (MRI) with gadolinium. However, the recent identification of the association between nephrogenic systemic fibrosis (NSF) and gadolinium administration has created significant challenges for urologists and radiologists when faced with the need for evaluation with contrast-enhanced cross-sectional imaging. In this review, we summarize the most comprehensive articles discussing both NSF and CIN and present a straightforward, evidencebased algorithm to determine the appropriate approach to cross-sectional imaging for all patients, as well as future directions regarding cross-sectional imaging. Materials and methods: A MEDLINE literature search for review articles from 1966 to August 2009 was performed. Selected additional articles for specific topics were also reviewed. This search yielded a total of 25 articles for NSF and 28 for CIN that were reviewed. Results: The pathophysiology and risk factors of NSF and CIN are discussed, as well as potential interventions to decrease either morbidity or incidence. A multidisciplinary (urologist, nephrologist, radiologist) evidence-based algorithm is introduced for managing patients in need of cross-sectional imaging. Conclusions: The associated risks of contrast-enhanced, cross-sectional imaging has created significant challenges for urologic evaluation. We propose an evidence-based approach to guide patient therapy, which can minimize patient risk and physician anxiety, while simplifying the decision-making process.