To assess diagnostic informative value of specific autoantibodies (AAB)--antikeratin antibodies (AKA), antiperinuclear factor (APF) and antibodies to cyclic peptide containing citrullin (CCP) from the family of antifilaggrine autoantibodies (AFA)--in rheumatoid arthritis (RA).
A total of 121 patients with RA and 45 patients with seronegative spondylarthropathies. Rheumatoid factor was detected with latex agglutination. AKA and APF were estimated with indirect immunofluorescence the substrate of which was series frozen sections of rat esophagus in the middle third of 4 mcm and cells of the epithelium of the internal surface of healthy donor's cheek. For detection of antibodies to cyclic peptide, the test DIASTAT Anti-CCP ELISA (Axis Shield, Great Britain) was made.
The RF was detected in 67.8% patients with RA; AKA, APF and antibodies to CCP--in 43.6, 52.9 and 68.0% patients, respectively. AKA were most specific for RA (100%) while the RF was least specific among the AAB studied (87%). Simultaneous use of RF and AFA allows AAB detection in 84% RA patients at early stages of the disease. AFA were detected in patients with high clinico-laboratory activity of the process, high indices of functional joint insufficiency. 95% of all cases of destructive arthritis were detected in patients with RF, AKA, APF and antibodies to CCP.
For RA patients it is necessary to determine both RF and AFA. Detection of AFA allows early diagnosis of RA as well as to single out patients with more aggressive course of the disease and unfavourable prognosis.