Normal CSF ferritin levels in MS suggest against etiologic role of chronic venous insufficiency

Chronic cerebrospinal venous insufficiency (CCSVI) has been suggested to be a possible cause of multiple sclerosis (MS). If the presumed mechanism of venous stasis-related parenchymal iron deposition and neurodegeneration were true, then upregulation of intrathecal iron transport proteins may be expected. This was a cross-sectional (n = 1,408) and longitudinal (n = 29) study on CSF ferritin levels in patients with MS and a range of neurologic disorders. Pathologic (>12 ng/mL) CSF ferritin levels were observed in 4% of the control patients (median 4 ng/mL), 91% of patients with superficial siderosis (75 ng/mL), 73% of patients with a subarachnoid hemorrhage (59 ng/mL), 10% of patients with relapsing-remitting MS (5 ng/mL), 11% of patients with primary progressive MS (6 ng/mL), 23% of patients with secondary progressive MS (5 ng/mL), and 23% of patients with meningoencephalitis (5 ng/mL). In MS, there was no significant change of CSF ferritin levels over the 3-year follow-up period. These data do not support an etiologic role for CCSVI-related parenchymal iron deposition in MS.