The Diagnostic Significance of Intrathecal Synthesis of Antibodies Against Measles, Rubella, and Varicella Zoster Viruses in the Differential Diagnosis of Demyelinating Diseases of the Central Nervous System

Introduction. The basis of autoimmune inflammation in multiple sclerosis (MS) is the polyclonal activation of B lymphocytes in the central nervous system, followed by intrathecal immunoglobulin production, caused by the synthesis of antibodies to measles, rubella, and varicella zoster viruses (MRZ reaction).

The study aimed to assess the possibility of using the IgG index, oligoclonal immunoglobulin synthesis, the permeability coefficient of the blood-brain barrier, specific indices of antibodies against measles, rubella, and varicella zoster viruses with the calculation of the MRZ reaction in the diagnosis of MS, neuromyelitis optica, and acute disseminated encephalomyelitis.

Materials and methods. The study included 40 patients with the following diagnoses: MS (n = 19), acute disseminated encephalomyelitis (n = 11), and neuromyelitis optica (n = 10). Intrathecal synthesis indicators were measured in all patients in paired samples of cerebrospinal fluid and serum.

Study results. In the study group, the MRZ reaction was a specific test for the diagnosis of MS and was not found in neuromyelitis optica or acute disseminated encephalomyelitis. An increase in the IgG synthesis index was observed in only 90.5% of patients with MS, and oligoclonal IgG was detected in only 71.4% of cases. Elevated albumin quotient values are not typical for MS, which characterizes the degree of permeability of the blood-brain barrier.

Conclusion. The MRZ reaction is a highly specific laboratory marker for verifying MS. It also enables differential diagnosis of MS and other demyelinating diseases.