Cerebrospinal fluid amino acid concentrations in patients with viral and tuberculous meningitis.

Serial measurements have been made of the cerebrospinal fluid and plasma amino acid concentrations in 11 patients with viral meningitis and in four with tuberculous meningitis. A small increase in the concentrations of a few amino acids in cerebrospinal fluid has been found in a viral meningitis in contrast to a marked increase in most amino acids in tuberculous meningitis. The findings are compared with those found in patients with purulent meningitis and the possible causes and the diagnostic significance of these findings are discussed.