Measurements of IgG and albumin in CSF and serum in various neurological diseases
Abstract Many neurological diseases may cause increase of protein in the cerebrospinal fluid (CSF), especially IgG. Breakdown of blood brain barrier (BBB) as well as increased de novo central nervous system (CNS) IgG synthesis may result in an elevation of IgG in the CSF. To assume that the increase of CSF IgG was due to local synthesis but not to BBB damage, Link and others suggested using a more refined quotient, i.e. the IgG index. However, for evaluating local IgG synthesis, the following equation was used (modified from Tourtellotte) de novo CNS IgG synthesis II = [(C. IgG-S.IgG/278.7)-(C.Alb-S.Alb/143.1) X (S. IgG/S. Alb) X 0.43] X 5. In this study we collected 62 cases of various neurological diseases and used the nephelometer to measure their IgG and albumin level in both sera and CSF. There were 4 cases of encephalitis, 17 cases of meningitis, 16 cases of multiple sclerosis, 11 cases of other neurological diseases and 14 cases of control group. The mean value of CSF IgG was 4.1 mg/dl in control group, 21.1 in encephalitis, 11.3 in meningitis, 4.7 in multiple sclerosis and 12.9 in other neurological diseases. The mean value of IgG index was 0.52 in control group, 1.43 in encephalitis, 1.07 in meningitis, 0.68 in multiple sclerosis and 1.11 in other neurological diseases. The mean value of modified de novo CNS IgG synthesis was -0.35 mg/day in control group, 48.79 in encephalitis, 25.48 in meningitis, 6.59 in multiple sclerosis and 15.01 in other neurological diseases.(ABSTRACT TRUNCATED AT 250 WORDS)