Department of Pediatrics, V.N.Karazin National University, Kharkiv, Ukraine
Introduction. Autoimmune thyroiditis (AIT) is a chronic inflammatory disorder of the thyroid gland caused by abnormal blood antibodies and white blood cells that mistakenly attack and damage healthy thyroid cells. As accompanying disease AIT with rheumatic decease was studied in adult. Clinical manifestation of Juvenile Rheumatoid Arthritis (JIA) in children with AIT is not investigated deeply.
Objective. It was to analyze the clinical presentation in patients with JIA which is accompanied by AIT and possible relations with polymorphism of genes of folate cycle enzymes.
Materials and Method. The study included 9 patients with JIA of age group 2-18 years. Children were divided in to 2 groups according to presenting of AIT. 25 % of patients, who developed AIT, were placed in the main studying group, other – in comparison group. The diagnosis of AIT was based on increased level of thyroperoxidase antibodies, stT4, stT3 and specific features on ultrasound of thyroid gland. The megerment 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 129) by polymerase chain reaction (PCR) was performed for all patients. For statistical processing of materials stagraphics 3.0 and Student-Fischer test were used.
Results. In children with AIT infection as a trigger factor of manifestation of JIA more frequency (p<0.001) was found. In group of patients with AIT more common symptom of JIA onset was arthritis of knee joints (p<0.001) in comparison with children of 2 group, where JIA began from fever in 26.6 % patients, from rush - 14.3 %. Joints syndrome in persons from I group characterized by more frequent involving of ankle joints (p<0.001), presence of regional amyotrophy (p<0.001), proliferative type of arthritis without acute joint pain and swelling and with deformation and decreased range of motion of affected joints (p<0.001), fast development of limited joints function I-III degree (p<0.001). Children with JIA in accompanying with AIT more frequently had neutral alleles (AA) of MTHFR1298 gene (p<0.001) and heterozygous genotype of risk allele (AC) of MTHFR677 gene (p<0.001) in comparison with persons of II group. Differences of genotypes of MTR and MTRR genes in comparison groups fell just short of statistical significance.Conclusion. Clinical presentation in patients with JIA which is accompanied by AIT is different in comparison with patients with JIA without AIT, it characterized by manifestation from knee joints, frequent involving of ankle joints, proliferative type of arthritis, fast development of limited joints function, frequently presenting of neutral alleles (AA) in MTHFR1298 gene and heterozygous genotype of risk allele (AC) of MTHFR677 gene.
