Guillain-Barre syndrome (GBS) is a polyradiculoneuropathy characterized by a rapidly progressive bilateral paresis of the limbs. Nadir is typically reached within a number of days or weeks, followed by a recovery that is generally much slower and often incomplete. Guillain-Barre syndrome is usually preceded by infection or other immune stimulation that induces an aberrant autoimmune response targeting peripheral nerves and their spinal roots.IVIG and Plasmapheresis are used first line treatments in GBS treatment. For better assessment of treatment response, biomarkers reflecting Plasmapheresis and IVIG efficacy are needed. Aim of this study is to determine serum albumin as an independent biomarker for clinical outcome in plasmapheresis treated-GBS patients