Antinuclear antibodies (AHA). The frequency of AHA detection in UHA depends on the form of the onset of the disease and the substrate used to detect them by immunofluorescence (usually the liver of rats or mice). AHA detection in girls with mono- and oligoarthritic onset of YUHA is almost 100% risk of developing chronic uveitis. In these patients, the presence of AHA is closely associated with the specificity of HLA — DR5. Of particular importance is the detection of AHA in the systemic onset of the disease, since these forms subsequently occur with systemic manifestations and frequent viscerites already in the early stages. A similar variant of RA adults is even called borderline with systemic lupus erythematosus.
The overall level of complement. Its determination is usually carried out by assessing the hemolytic activity of the blood using 50% hemolysis. The decrease in hemolytic activity indicates a possible increase in the consumption of complement, and the presence of congenital deficiency, mainly of the Cr component. The combination of hypocomplementation with the presence of RF, as a rule, is observed in patients with a severe course of UHA with pronounced extra-articular manifestations (vasculitis, damage to the lungs, kidneys, etc.).
Circulating immune complexes (CIC). Various methods are used to identify the CEC. It is believed that, at least, it is necessary to use two methods, one of which must be complement-binding. The use of the CIC method for determining the serum anti-complementary activity made it possible to identify a close correlation between CI K and the severity of the disease, as well as the involvement of the internal organs in the pathological process. Persistent persistence of the CEC, as a rule, coincides with the rapid progression of the process.
Serum immunoglobulins. The study of serum immuno-globulins (Ig) by the method of radial immunodiffusion according to Mancini made it possible to identify not only the activation of the immunocompetent system, but, above all, to exclude the presence of congenital insolvency of immunity. The level of immuno-globulins, especially IgG, is closely correlated with the activity of the process . In case of violation of the synthesis of immunoglobulins, a sluggish course of the JUHA, mainly articular lesions, high susceptibility to infection, often the presence of a chronic bronchopulmonary process. It is noteworthy that selective IgA deficiency occurs 5 times more often with rheumatoid tumors compared with other forms of YUHA. The course of uveitis is characterized by continuous recurrence and rapid development: cataracts. In the forms of total violation of the synthesis of Ig type: Bruton synovitis is quite pronounced, but despite the long-term existence, there is no rapid progression.