High signal in the cerebrospinal fluid following prior gadolinium administration in a patient with renal impairment.

Increased signal intensity in the cerebrospinal fluid (CSF) on magnetic resonance imaging due to the presence of gadolinium is rarely observed, but has been seen in patients with brain or spinal pathology or underlying renal impairment. We report this phenomenon in a 66-year-old woman with diabetic nephropathy and discuss the possible pathogenesis of the scan findings. Recognition of this unusual finding, and features distinguishing it from other causes of high CSF signal intensity, such as subarachnoid haemorrhage and protein in the CSF, are emphasised to help prevent diagnostic errors.