To detect endogenic intoxication syndrome (EIS) and to assess its severity depending on clinical manifestations of rheumatoid arthritis (RA) using laboratory tests.
Laboratory tests including analysis of synovial fluid, blood count with estimation of leucocytic intoxication index, urinalysis, total protein and protein fractions, seromucoid, syalic acids, peroxide-antioxidant balance, metabolism of proteoglycanes, immunological tests were made in 162 patients with documented RA and 86 healthy controls. Content of middle mass molecules served as an integral biochemical EIS marker.
Inflammatory destructive processes in the affected tissues of RA patients lead to marked systemic metabolic and immune disorders accompanied with EIS. Severe EIS are associated with severe metabolic disorders. A significantl rise (p < 0.05) in content of middle mass molecules in the serum was found in all RA patients including in the disease onset and in minimal activity of inflammation and presence of only mono-olygoarthritis of the knee joints.
RA patients develop EIS the severity of which depends on the activity and distribution of the inflammatory process but not on the disease stage. Metabolic disorders in RA patients can be assessed with an effective method--blood serum middle mass molecule assay.