Calprotectin levels in the cerebrospinal fluid reflect disease activity in multiple sclerosis

Calprotectin is produced by activated monocytes and microglia, and cerebrospinal fluid (CSF) levels could be a marker of neuroinflammation. Calprotectin was detectable in CSF from 13.8% of normal controls, compared to 90.5% of patients with neurological infections (p < 0.001). In CSF from patients with multiple sclerosis (MS) and clinically isolated demyelinating syndrome, calprotectin was detected in 64.7% within 2 weeks after symptom debut compared to 30.8% between 2 and 4 weeks and 17.0% thereafter (p < 0.001). We conclude that CSF calprotectin reflects the disease activity in MS but does not discriminate between MS and other inflammatory or infectious conditions.