Purpose: To assess the renal tolerance of 1.0 mol/L gadobutrol as an electrically neutral contrast agent at magnetic resonance (MR) imaging in patients with impaired renal function.
Materials and methods: Twenty-one patients with impaired renal function were enrolled in this prospective randomized study and classified into two subgroups according to their creatinine clearance: group 1 (n = 12), less than 80 mL/min (<1.33 mL/sec) and greater than 30 mL/min (>0.50 mL/sec); group 2 (n = 9), less than 30 mL/min (<0.50 mL/sec) and not requiring dialysis. Gadobutrol (1.0 mol/L) was injected intravenously at randomly assigned doses of either 0.1 or 0.3 mmol per kilogram of body weight. Changes in vital signs, clinical chemistry, and urinalysis results, including creatinine clearance, were monitored before, at 6 hours, and then every 24 hours until 72 hours (group 1) or 120 hours (group 2) after intravenous injection of gadobutrol. Hematologic results were checked every other day.
Results: No serious adverse event occurred, and no clinically relevant changes in vital signs, hematologic results, clinical chemistry, or urinalysis results were detected in the observation period. Markers for glomerular filtration (creatinine, cystatin C, beta2-microglobulin, creatinine clearance) and tubular function (N-acetyl-beta-D-glucosaminidase, alpha1-microglobulin) were unaffected by gadobutrol in both groups.
Conclusion: Gadobutrol did not affect renal function and, therefore, proved to be a safe MR contrast agent in patients with impaired renal function. Even in patients with marginal excretory function (creatinine clearance, <30 mL/min [<0.50 mL/sec]), prehydration or treatment with diuretics or hemodialysis are not required after the administration of gadobutrol.