Measuring a patient’s glomerular rate before administering a gadolinium-based contrast agent (GBCA) can eliminate new cases of nephrogenic systemic fibrosis (NSF), according to a study conducted by researchers at Massachusetts General Hospital (MGH) and Harvard Medical School and slated for publication in the July issue of Radiology.
The study reveals that gadolinium contrast should never be administered to patients currently undergoing dialysis or those with a very low estimated glomerular filtration rate (eGFR) of less than 30 mL/min/m 2. Those patients are most susceptible to NSF. However, researchers found, a maximum GBCA dose of 20 mL for patients with a low eGFR (less than 60 mL/min/m 2) is acceptable.
Widespread tissue fibrosis characterizes the adverse reaction to the contrast agent. Patients with NSF experience an increase of collagen in the tissues, causing thickening and hardening of the skin at the extremities, and often resulting in immobility and tightening or deformity of the joints.
MGH implemented restrictive guidelines on the administration of gadolinium contrast in 2007, subsequently preventing any new cases of NSF. These guidelines stipulate that patients who are older than 60 or are at risk for kidney disease be administered a blood test to estimate GFR, which measures the rate of fluid flow through the kidneys. Lead researcher Hani Abujudeh, MD, an associate professor of radiology at Harvard, and his colleagues reviewed the hospital's medical records from January 2002 through December 2007. They found that prior to the adoption of the guidelines and during the transition period, 113,120 contrast-enhanced MRI exams were performed, and 34 cases of NSF were subsequently identified. Conversely, after the guidelines had been enacted, 52,954 contrast-enhanced MRIs were performed, with no new cases of NSF identified.
Abujudeh urges that the public be made aware that gadolinium agents are safe for most patients, and that the risk of NSF should not deter them from GBCA-enhanced exams such as MRI studies. The study findings, he asserts, prove that contrast administration guidelines are effective, and strategies can be put into practice to ensure patient safety during gadolinium contrast use.