Cerebrospinal fluid IgG, IgA, IgM, IgD, and IgE levels in central nervous system disorders.

Using a radioimmunoassay, we evaluated the cerebrospinal fluid content of IgG, IgA, IgM, IgD, and IgE in multiple sclerosis, viral meningitis, and tumors. Abnormal immunoglobulin levels occurred in all conditions, reaching 13 times the norm for IgM in multiple sclerosis and 5 times the norm in aseptic meningitis. Striking increases also occurred with IgA, IgM, and IgE in benign and malignant (both primary and metastatic) tumors of the CNS. Furthermore, the immunoglobulin-protein ratio was calculated. In aseptic meningitis and multiple sclerosis, the ratio was significant as compared to the norms.