КЛИНИКО-ДИАГНОСТИЧЕСКОЕ ЗНАЧЕНИЕ АНТИНУКЛЕАРНЫХ АНТИТЕЛ В ПРАКТИКЕ ПЕДИАТРА (ЧАСТЬ I)

Abstract

In recent decades, there has been an increase in the incidence of various autoimmune, including rheumatic diseases, while their debut has been shifted to an earlier age. The clinical picture of rheumatic diseases is distinguished by severe polymorphism; therefore, laboratory diagnostic methods are important for diagnostic search. One of the most widely used tests in the rheumatological practice is the detection and identification of antinuclear antibodies (ANA). ANA are a large group of autoantibodies (auto-Abs) directed against various cell structures, including not only the nucleus but also the nuclear membrane, mitotic apparatus, cytoplasm components and cell organelles, as well as cell membranes. Different methods are used for testing, but the method of ANA detection through indirect immunofluorescence antinuclear antibody test (IF-ANA) is recommended as a “gold standard” with human laryngeal carcinoma HEp-2 cells being recognized as a standard substrate. IF-ANA with HEp-2 has the highest diagnostic sensitivity compared with other methods, it includes the phase of serial dilutions of positive serums and a visual analysis of the type of glow, the list of which currently has 30 patterns. ANA glow types are caused by various auto-Abs that respond with antigens located in the nucleus and cytoplasm of the HEp-2 cells line. Assessment of the type of glow in conjunction with clinical and laboratory data allows planning of further examination with confirming tests to determine the specificity of ANA, some of which, in particular, are auto-Abs to DFS70 antigen, which in the absence of other types of autoantibodies, are more likely to doubt the presence of a systemic rheumatic disease. The diagnostic specificity of various screening techniques for ANA detection is relatively low, they are detected with a fairly high frequency in patients with other diseases and in healthy individuals of different gender and age, including children.