Khadzhynova Y. Vitamin D supply and prevention of its deficiency in children with juvenile idiopathic arthritis

The issue of vitamin D (VD) supply of patients with juvenile idiopathic arthritis (JIA) in the conditions of modern disease management . The relationship between the status of VD in children with JIA and the severity of the pathological process has been supplemented. It is shown that VD deficiency is present in 83.56% of patients, mainly in polyarticular and undifferentiated variants, and the average level of 25(OH)VD is significantly lower than in the control group, regardless of age and sex of patients. For the first time it was proved that VD deficiency depends on the integrated degree of disease activity (according to the JADAS-27 scale), among which the prevalence of inflammation (number of active joints) and the degree of dysfunction of the joint apparatus is predominant. Insufficient levels of VD in the oligoarticular variant of JIA have been further associated with the age of patients and functional status of the kidneys; with polyarticular – with the age of onset and duration of the disease; in undifferentiated arthritis - with the duration of the disease, ESR and functional status of the kidneys. Gender differences in the development of VD-deficiency states have been established: for boys with JIA, the degree of damage to the joint apparatus is an important factor in reducing the content of VD; for girls – changes in calcium-phosphorus homeostasis. A common negative factor for low serum VD levels is the level of antinuclear antibodies (ANA). For the first time, it has been shown that in children with JIA, VD deficiency is observed throughout the calendar year, associated with reduced body weight and older patients. The study expands the understanding of the state of calcium-phosphorus homeostasis, parathyroid hormone levels and bone status depending on the supply of VD in children with JIA, which may be the basis for more effective methods of preventive measures to prevent osteopenic syndrome in this category of patients. The importance of reducing the level of phosphatemia and increasing the concentration of ionized calcium in conditions of VD deficiency is shown. For the first time, the assessment of VD status in children with JIA on the background of additional supplementation in accordance with current recommendations, which allowed to determine the criteria for its low effectiveness. Study has shown that children with JIA need to be monitored for VD status and corrected in a timely manner by prescribing prophylactic or therapeutic doses of VD3 according to established values of insufficiency or deficiency, starting from the onset of the disease. It was substantiated that pediatric patients with JIA are shown to determine the level of 25 (OH) D in the serum once every 6 months and the appointment of an additional continuous intake of 2000 IU of cholecalciferol. It was found that the effectiveness of additional VD supplementation is interdependent on clinical and laboratory parameters, namely: age of patients, their physical development (BMI), disease duration, degree of disease activity (data of JADAS-27 scale, ESR, CRP and levels of ANA and RF); the number of affected and active joints, as well as indicators of calcium-phosphorus homeostasis. It was found when ascertaining insufficient supply of VD in pediatric patients with JIA the dose of VD3 can be increased to 3000-4000 IU for 1 to 3 months depending on the degree of deficiency.