In cerebrospinal fluid (CSF) immunoglobulins are normally present in small amounts. Raised IgG levels in cerebrospinal fluid can be observed in central nervous system (CNS) infections, an inflammatory syndrome, or in neurological conditions such as multiple sclerosis.
A raised IgG concentration in cerebrospinal fluid may be due to hemato-meningeal damage and/or intrathecal IgG synthesis. Parallel dosages of albumin and IgG in serum and in cerebrospinal fluid make it possible to differentiate between these two mechanisms and to demonstrate an intrathecal IgG synthesis.
