Introduction Systemic Lupus Erythematosus (SLE) is a rheumatic multi-systemic chronic inflammatory disease in children, which is characterised by autoantibodies directed against self-antigens, immune complex formation, and immune dysregulation, resulting in damage to essentially any organ.

Objectives The aim was to assess the peculiarities of clinical presentation of systemic lupus erythematosus in children with different genotypes of folate cycle genes.

Methods The study involved 12 children with SLE aged from 7 to 18 years. There were 1 male and 11 female with disease duration from 7 month to 11 years. Patients were divided into 3 groups corresponding to the number of genes with risky genotypes. Group 1 included patients, who had one gene with risky genotype and 3 genes with neutral genotype; Group 2 consisted of children, who had 2 genes with risky genotype and 2 genes with neutral genotype; Group 3 included persons, who had 3 genes with risky genotype and 1 gene with neutral genotype. Assessment of children was based on physical, laboratory examination and instrumental tests. The measurement of genotypes of genes of folate cycle, such as 5-methyltetrahydrofolate-homocysteine methyltransferase (MTR), 5–methyltetrahydrofolate-homocysteine methyltransferase reductase (MTRR), 5,10–methylenetetrahydrofolate reductase C677T and A1298C variants (MTHFR-677 and MTHFR–1298) were made by polymerase chain reaction. For the statistic processing of the material Stagraphics 3.0 for Windows was used.

Results Patients of Group 3 more frequently had risky genotype of MTHFR1298 gene (A/C or C/C) in comparison with other 2 groups (p<0.001), risky genotype of MTR (A/G or G/G) and MTHFR677 (C/T or T/T) genes compared with Group 1 (p<0.001). Corresponding to analysis of anamnesis, disease onset in children of Group 1 the most common included in 33% cases the skin syndrome (rash), arthritis and bleeding. 50% of patients of Group 2 had signs of nephritis as a prominent due to beginning of SLE that was more frequent than in Group 1 (p<0.001). Arthritis was determined as a main syndrome of disease onset in children of Group 3 (66.7%), it was higher compared with Group 2 (p<0.001). At the moment of investigation general stage was assessed as a satisfactory the most frequent in patients of Group 3 than in others (p<0.001). Nephritis and arthritis were the most common for children of Group 1 and 2 (p<0.001). Neurologic symptoms and Antiphospholipid syndrome were more specific for patients of Group 2 (50%, p<0.001). Myocarditis was found on the average in 42% of children without statistical confidence between studying Groups.

Conclusions According to our findings, patients with different number of risky genotypes of folate cycle genes have different clinical presentation. The most severe syndromes were specific for children who had risky genotype of 2 folate cycle genes. The best case scenario of SLE was detected in patients who had risky genotype of 3 folate cycle genes.

Disclosure of interest None declared