INTERLEUKIN 6 METABOLISM AND FUNCTIONAL KIDNEY STATUS IN EARLY RHEUMATOID ARTHRITIS

Much attention paid to the problem of early rheumatoid arthritis (eRA) is due to its socio-economic significance. Kidney damage in RA occurs is reported as highly prevalent ranging from 36 to 73% and of great clinical significance, since it contributes much to the course of the underlying disease and increases mortality. The aim of the study was to evaluate the interrelation between interleukin-6 metabolism (IL-6) and impaired kidneys functional status at the debut of rheumatoid arthritis. Material and methods. This study included 35 patients aged over 18 with eRA. The average age of patients was 50.71 ± 2.25 years (from 18 to 76 years), there were 80% of women; the average duration of the disease at the time of the initial examination was 9.21 ± 0.43 months. Results. The index of microalbuminuria was found to increase by 154.57% with an elevation of IL-6 values ​​above 50 percentile. Also, microglobulinuria values ​​increased by 207.14% in patients of the subgroup with IL-6 values ​​above 50 percentile compared to the patients below 50 percentile. The glomerular permeability index, reflecting the average concentration of albumin in the glomerular ultrafiltrate, increased by 87.93% along with the increase in pro-inflammatory marker IL-6 in patients of the subgroup above 50 percentile relative to patients with low IL-6 values. Progressively with an increase in IL-6 values, a renal functional reserve dropped by 69.42% between subgroups below and above 50 percentile. Conclusion. Elevation of pro-inflammatory cytokine IL-6 is associated with changes in key markers of renal function, reflecting the presence of a direct connection between the degree of inflammatory activity in RA and the degree of renal dysfunction as the disease progresses.