RESUMO
AIM: Determine if serum levels of tau and BDNF can be used as severity biomarkers in multiple sclerosis (MS). PATIENTS & METHODS: Subjects with MS, older than 18 and younger than 55 years old were included; 74 patients with a diagnosis of relapsing-remitting MS, 11 with secondary-progressive MS, and 88 controls were included. Total tau and BDNF were measured by Western blot. RESULTS: Increased tau and decreased BDNF in MS patients compared with controls was found. Total-tau has a peak in relapsing-remitting MS, the second decile of the multiple sclerosis severity score, and in the lowest expanded disability status scale and is no different than controls for secondary-progressive MS patients and the most severe cases of MS. CONCLUSION: BDNF is a good biomarker for diagnosis of MS but not for severity or progression. Tau appears to have a more active role in the progression of MS.