ADVISABILITY OF THYMECTOMY IN YOUNG PATIENTS WITH THYMUS-INDEPENDENT MYASTHENIA GRAVIS IN THE PRESENCE OF BIOMARKERS SPECIFIC FOR PATIENTS WITH THYMOMA

Summary. The aim is to assess the presence of specific markers in patients with thymus-independent and thymus-dependent myasthenia gravis for choosing treatment tactics. Materials and methods. The presence of specific markers was assessed in 138 patients with thymus-independent (M – myasthenia gravis without thymus changes) and thymus-dependent (MH – myasthenia gravis with thymus hyperplasia, MT – myasthenia gravis with thymoma) for the choice of treatment tactics. We used methods of enzyme immunoassay, spectrophotometry, light and fluorescence microscopy. Results and discussion. The relationship between the clinical phenotypes of myasthenia gravis and the variants of HLA leukocyte antigen diplotypes was revealed: in young patients with thymus-independent myasthenia gravis (M), a high heterogeneity of the genotypic markers HLA-DR (DR1, DR2, DR3, DR5, DR7) was observed. Patients with thymus-dependent myasthenia (MT) had only the HLA DR2 and HLA DR7 diplo- and haplotypes. The presence of HLA DR2 and HLA DR7 haplotypes and certain changes in the complex of biomarkers (anti-nuclear antibodies, innate immunity and humoral sensitization) in some young patients with M with disease progression led to the development of myasthenia gravis with thymoma (MT) at an older age. Conclusions. The prognosis of the progression of myasthenia gravis and the development of remission can be made using genomic (the presence of certain HLA-DR haplotypes) and molecular (anti-nuclear antibodies ANA, different fractions of medium molecular weight peptides, circulating immune complexes) biomarkers, that can be used for the choice of treatment tactics.