Anti Nuclear Antibodies (ANA)
- Description
- Anti-nuclear antibodies (ANA) are the most frequently encountered autoantibodies in rheumatic diseases which include systemic lupus erythematosus (SLE), mixed connective tissue disorder (MCTD) and autoimmune hepatitis. However, a positive ANA does not signify the presence of disease as ANA may be positive at low titres in elderly individuals. This investigation is based on indirect immunofluorescence using a HEp-2 cell line as substrate. The laboratory tests for only for antibodies of the IgG isotype (other isotypes can be investigated by request). Sera are initially tested at 1:40 dilution and if positive the titre of ANA determined. ANA reacts with antigenic nucleoproteins in the nucleus and cytoplasm which includes Sm, SSA/Ro, SSB/La, RNP, Jo-1 and Scl-70.. ANA produces a number of IIF staining patterns, homogenous, rim, speckled, nucleolar and anti-centromere. The staining pattern has a low sensitivity and specificity for different rheumatic diseases.
- Reference range
- Negative / To Confirm
- Units
- Titre value
- Testing site
- Synnovis : Reference Services : Blackfriars Hub
- Laboratory
- Diagnostic Immunology
- Sample type and volume required
- Clotted (Gold top vacutainer)
- Special sample instructions
All tests are compromised by prolonged transit times. For this reason, date of bleed and date of postage must be provided with each request.
- Storage and transport
- Serum stored at 4°C should be sent by first class post
- Turnaround time
- 4 working days
- Time limit for extra tests
- 10 days