Total immunoglobulin (IgG, IgM, IgA) in cerebrospinal fluid in late syphilis: classification and clinical interpretation of occurring alterations

Levchik N.K., Ponomareva M.V., Zilberberg N.V., Polishchuk A.I.

Ural Research Institute of Dermatovenereology and Immunopathology, Yekaterinburg, Russia

Aim: to study alterations in the composition of total immunoglobulins (IgG, IgM, IgA) of the cerebrospinal fluid in patients with late syphilis, to propose their classification and clinical interpretation of variants.
Methods. A set of cerebrospinal fluid tests, including the immunoglobulin (IgG, IgM, IgA) concentration, indicators of intrathecal immunoglobulin synthesis and permeability of the blood-cerebrospinal fluid barrier was conducted in 303 patients with late syphilis who had no signs of other central nervous system pathology.
Results. The alterations in the composition of total immunoglobulins (IgG, IgM, IgA) were categorized into six variants, depending on the increase in immunoglobulin levels, evidence of intrathecal synthesis or the absence of deviations of studied parameters. The explored relationships between the variants of total immunoglobulin reaction in cerebrospinal fluid and clinical and laboratory features of the patients were biologically and clinically plausible. Specific inflammatory process could be confirmed by applying the developed methodology in 37% (22−54%) of patients with “possible” neurosyphilis, and in 5%(3−9%) of patients with “inconclusive” results.
Conclusion. The findings show existing patterns of intrathecal humoral immune response in patients with late syphilis. The application of the developed classification of total immunoglobulin reaction in cerebrospinal fluid allows for improved recognition accuracy for the consequences of T. pallidum invasion into the central nervous system.