- Clinical science
Antibody diagnostics play a vital role in the differential diagnosis of autoimmune diseases. Many of these autoantibodies can be differentiated into antibodies against nuclear antigens (ANAs) and antibodies against cytoplasmic antigens (ANCAs). Although both of these antibodies are detectable in numerous autoimmune diseases, elevated ANAs are typical for connective tissue diseases and elevated ANCAs for vasculitis. Diagnosis of individual conditions can be further supported by detecting disease-specific ANAs or ANCAs, such as anti-dsDNA in systemic lupus erythematosus or c-ANCA in Wegener's granulomatosis.
- ANAs are comprised of numerous antibodies against specific nuclear antigens.
- In addition, ANAs include autoantibodies against DNA and histones.
- ANAs were previously further classified into ENA (extractable nuclear antigen antibodies).
- ANAs specifically target antigens within the nucleus.
- ANAs are determined via a standardized immunofluorescence assay based on the pattern of fluorescence that is produced.
- Elevated ANA levels are observed in various autoimmune diseases, especially in the diseases listed below.
- An increase is typically observed in connective tissue diseases, but may also be found in, e.g., rheumatoid arthritis (RA), autoimmune hepatitis, and vasculitides.
- In general, elevated ANA levels are considered nonspecific; exact diagnosis requires determination of individual antibodies.
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- Description: ANCAs are comprised of antibodies against specific cytoplasmic antigens
| c-ANCA |
| p-ANCA |