Little change in cerebrospinal fluid amino acids in subtypes of multiple sclerosis compared with acute polyradiculoneuropathy

Levels of free amino acids were determined in randomised, blinded samples o f cerebrospinal fluid (CSF) from patients with relapsing-remitting or chron ic progressive multiple sclerosis (MS), all in the active phase of disease. The levels were compared with amino acid amounts in patients with an acute polyradiculoneuropathy (Guillain-Barre syndrome (GBS)) and a control popul ation of patients with no known neurological disease or deficit. The data d id not indicate any significant changes in amino acid levels between MS sub groups. The only significant differences between MS patients and controls w ere a modest reduction in glutamate and a slight increase in taurine, but t he changes were so small that the biological relevance is dubious. These re sults contrasted with the marked increases for many amino acids in CSF from patients with acute polyradiculoneuropathy compared with controls. The ami no acid profile in cerebrospinal fluid (CSF) does not appear to provide evi dence of differential pathology in multiple sclerosis (MS). The increase in hydrophobic amino acids and lysine in CSF from patients with acute polyrad iculoneuropathy is consistent with transudation over the blood-CSF barrier following an infection. The increases in glutamine and alanine may reflect increased nitrogen removal from brain. (C) 2001 Elsevier Science Ltd. All r ights reserved.