Immunology Rheumatic Disease Serology (EN) Codes and Comments Tables Table 1 Code ENA Code ENA A B C J L M N SS-A SS-B PCNA Jo1 PmSc Sm Neg O P Q R S U Ribosomal P Pos Ro52 RNP Scl-70 UPL Table 2 1. dsDNA This antibody is highly specific for SLE. 2. RNP This antibody is seen in the majority of patients with Mixed Connective Tissue disease but may be associated with other connective tissue disorders such as SLE. 3. SSA This antibody is associated with SLE, cutaneous lupus, primary Sjogren’s syndrome and neonatal lupus/heart block. 4. SSA, SSB These antibodies in combination are relatively specific for primary Sjogren’s syndrome. 5. Scl-70 This antibody is seen in the diffuse variant of scleroderma. 6. Jo-1 This antibody is seen in about 30% of patients with autoimmune myositis, often associated with interstitial lung disease. 7. The clinical significance of this antibody is unknown. 8. Absence of dsDNA does not exclude the diagnosis of SLE. 9. PM-Scl This antibody is suggestive of polymyositis/scleroderma overlap syndrome. 10. Ribosomal P This antibody is seen in SLE. 11. UPL The clinical significance of detection of a UPL is uncertain. 12. Negative for specificities detailed below. 16. Ro52 Ro52 antibodies are found in a number of autoimmune diseases including SLE, Primary Sjogren’s Syndrome and inflammatory myositis. They may occur in many inflammatory disease states. 17. Nucleosome Nucleosome antibodies typically segregate with systemic lupus erythematosis. 18. Sm This antibody is highly specific for SLE. Immunology Rheumatic Disease Serology (EN) Codes and Comments Tables Table 3 Comment Code 1. ACL IgG and IgM negative A small proportion of patients with antiphospholipid antibody syndrome have undetectable anticardiolipin antibodies. Testing for lupus anticoagulants and anti-B2GP1 is recommended if clinically indicated. 2. ACL IgM positive IgM anticardiolipin antibodies are less sensitive and specific than IgG anticardiolipin antibodies for the diagnosis of antiphospholipid syndrome, and have a weaker association with thrombotic events and/or recurrent pregnancy loss in patients with antiphospholipid syndrome. Repeat testing to assess antibody persistence is recommended, ideally after 12 weeks. 3. ACL IgG and IgM positive OR IgG ACL positive alone Moderate to high levels of IgG anticardiolipin antibodies are suggestive of the presence of the antiphospholipid syndrome. Their presence is also associated with an increased risk of a thrombotic event or recurrent pregnancy loss in patients with antiphospholipid syndrome. This risk appears to increase with the level of aCL positivity . Transient and/or low level antibodies have a much lower predictive value for antiphospholipid syndrome and may be found in a range of other inflammatory, infectious and malignant disorders. Repeat testing to assess antibody persistence is recommended, ideally after 12 weeks. 4. Anti-B2GP1 pos Positive IgG anti-B2GP1 antibodies are suggestive of the presence of the antiphospholipid syndrome, and are associated with an increased risk of a thrombotic event or recurrent pregnancy loss in patients with antiphospholipid syndrome. The combination of positive ACL, anti-B2GPI and lupus anticoagulant results is reported to be associated with an increased risk of thrombosis and/or pregnancy complications. Repeat testing to assess antibody persistence is recommended, ideally after 12 weeks. 5. Anti-B2GPI neg A proportion of patients with antiphospholipid antibody syndrome are negative for antibodies to B2GP1 but are positive for anticardiolipin antibodies due to the lower sensitivity of the anti-B2GP1 assay compared with the ACL assay. Testing for lupus anticoagulants and anticardiolipin antibodies is recommended if clinically indicated. 6. Anti-B2Gp1 pos and ACL pos The combination of positive ACL, anti-B2GPI and lupus anticoagulant results in combination with appropriate clinical features, is suggestive of the presence of the antiphospholipid syndrome. This combination of positive assay results is associated with an increased risk of thrombosis and/or pregnancy complications. Repeat testing to assess antibody persistence is recommended, ideally after 12 weeks.