Ask the Experts - APS with High Titer anti-SSa-La
Ask the Experts - APS with High Titer anti-SSa-La
A 44-year-old woman presented with a history of two thrombotic events (lungs and legs) in 1998. She was diagnosed antiphospholipid syndrome (APS), with high titer anticardiolipin antibodies; she was treated with prednisone, antimalarials, and nonsteroidal anti-inflammatory drugs. She is well now, taking an antimalarial and oral anticoagulant, with normal titer anticardiolipin antibodies. My question is why she would have high titer anti-SSA-La (1:6.400 in March and 1:51.200 in September 2000).
Orlando Souza, MD
The question concerns the significance of 2 high-titer positive tests for anti-SS-A (which actually is alternatively termed "anti-Ro"; Anti-SS-B is alternatively termed "anti-La"). These results are not likely to be false-positive because of their high titer and the fact that this woman has APS syndrome. Although she now has normal titer anticardiolipin antibodies, such titers can fluctuate significantly and she has been treated with immune-modulating agents.
Anti-SS-A antibodies are positive in 40% to 60% of patients with systemic lupus erythematosus (SLE) or Sjögren's syndrome, but are not usually positive in other autoimmune disorders. The likelihood is that your patient's APS is not primary, but instead a component of SLE. The signficance of anti-SS-A antibody positivity includes its association with so-called antinuclear antibody-negative SLE, in which a particular form of cutaneous involvement termed subacute cutaneous LE is common. In addition, I would be particularly concerned about this patient's obstetric and family history, and not simply because of the APS. In a woman of child-bearing potential, anti-SS-A antibody positivity is associated with a significant risk of neonatal SLE.
In this patient, I would be sure to assess for clinical symptoms and signs suggesting SLE, such as alopecia, photosensitivity, rash, Raynaud's phenomenon, oral ulcers, and renal disease, and to assess for sicca symptoms and salivary gland enlargement. I would also assess and review a broader serologic work-up, including ANA, DNA binding, C3, C4, and antibodies to Smith and RNP, as well as SS-A and SS-B.
A 44-year-old woman presented with a history of two thrombotic events (lungs and legs) in 1998. She was diagnosed antiphospholipid syndrome (APS), with high titer anticardiolipin antibodies; she was treated with prednisone, antimalarials, and nonsteroidal anti-inflammatory drugs. She is well now, taking an antimalarial and oral anticoagulant, with normal titer anticardiolipin antibodies. My question is why she would have high titer anti-SSA-La (1:6.400 in March and 1:51.200 in September 2000).
Orlando Souza, MD
The question concerns the significance of 2 high-titer positive tests for anti-SS-A (which actually is alternatively termed "anti-Ro"; Anti-SS-B is alternatively termed "anti-La"). These results are not likely to be false-positive because of their high titer and the fact that this woman has APS syndrome. Although she now has normal titer anticardiolipin antibodies, such titers can fluctuate significantly and she has been treated with immune-modulating agents.
Anti-SS-A antibodies are positive in 40% to 60% of patients with systemic lupus erythematosus (SLE) or Sjögren's syndrome, but are not usually positive in other autoimmune disorders. The likelihood is that your patient's APS is not primary, but instead a component of SLE. The signficance of anti-SS-A antibody positivity includes its association with so-called antinuclear antibody-negative SLE, in which a particular form of cutaneous involvement termed subacute cutaneous LE is common. In addition, I would be particularly concerned about this patient's obstetric and family history, and not simply because of the APS. In a woman of child-bearing potential, anti-SS-A antibody positivity is associated with a significant risk of neonatal SLE.
In this patient, I would be sure to assess for clinical symptoms and signs suggesting SLE, such as alopecia, photosensitivity, rash, Raynaud's phenomenon, oral ulcers, and renal disease, and to assess for sicca symptoms and salivary gland enlargement. I would also assess and review a broader serologic work-up, including ANA, DNA binding, C3, C4, and antibodies to Smith and RNP, as well as SS-A and SS-B.