THE PREVALENCE OF ANTIBODIES AGAINST JOHN CUNNINGHAMVIRUS IN PATIENTS WITH MULTIPLE SCLEROSIS –AS A STRATIFICATION OF THE PROGRESSIVE MULTIFOCALLEUKOENCEPHALOPATHY RISK DEGREE AT THIS DISEASE

Abstract

Introduction. Progressive multifocal leukoencephalopathy (PML) is a rare and severe demyelinating disease of the
white matter of the central nervous system (CNS) and caused by the John Cunningham virus (JCV). JCV infection has
become important for neurologists after reporting two cases of PML in patients with multiple sclerosis (MS) treated with
natalizumab.
Aim: To study the prevalence of antibodies against John Cunningham virus (JCV) in patients with multiple sclerosis and
identify the relationship between clinical, demographic characteristics and seropositivity and seronegativity for anti-JCV.
Materials and methods. We conducted a retrospective assessment of a database of MS patients registered at the
Multiple Sclerosis Center of Almaty, who are candidates for natalizumab, from April 2018 to June 2019. The diagnosis was
diagnosed in accordance with 2017 MacDonald's revised criteria. Several factors were studied, such as age, gender,
nationality, duration of illness, average score on the advanced EDSS disability rating scale, to determine cognitive function
on the MOCA scale during testing for anti-JCV antibodies and previous immunotherapy. The relationship between the
seropositivity of the anti-JCV antibody and the demographic characteristics and disease characteristics was evaluated.
Research results: Of the 71 examined patients with MS for the presence of antibodies against the JC virus, 76.1% were
women (54) and 23.9% were men (17). The average age was 41.2 ± 11.4 years, and the duration of the disease was 11.9 ±
8.7 years. Most patients 77.5% (55) had relapsing - remitting MS, and the average EDSS score in the study group was 3.75
± 1.45 points. The overall prevalence of seropositivity for anti-JC virus antibody was 85.9% (61), of which 73.8% were
women.
Conclusions: Thus, the study confirmed the high prevalence of anti-JCV antibodies in patients with MS by 85.9%. The
results of studies conducted to date confirm the prognostic value of measuring anti-JCV antibodies in assessing the risk of
PML, however, changes in JCV status must be considered.