When to consider seronegative APS?
👉recurrent episodes of thrombosis, especially arterial or unusual venous sites, without identifiable RFs for thrombosis
There is not one accepted set of criteria for seronegative APS
Note: In almost all cases, the presence of non-criteria manifestations
What are non-criteria manifestations of APS?
🔹Phosphatidylserine autoAbs -- will likely be included in the revision of the APS criteria
🔹Not all Abs to beta2-GPI are created equally; some are not clinically significant (binding to domain 1 with highest risk of thrombosis)
👉First, consider the presence of an inhibitor vs factor deficiency
👉Then, consider inhibitors besides lupus anticoagulants
3 steps to 1⃣screen 2⃣mix 3⃣ confirm the presence of lupus anticoagulant
Why is this important? Pts with lupus may develop acquired factor inhibitors (most commonly factor VIII) that can cause spontaneous & catastrophic bleeding 🩸
APS nephropathy: a spectrum of intra-renal pathology from acute thrombosis and TMA to chronic vascular lesions with fibrosis intimal hyperplasia