CAPS

Q: Catastrophic antiphospholipid syndrome (CAPS) by definition is characterized by severe? (select one)

A) thrombotic complications

B) bleeding complications

Answer: A

Catastrophic antiphospholipid syndrome (CAPS) is an intense life-threatening form of antiphospholipid syndrome (APS) characterized by severe thrombotic complications, microvascular as well as large-vessel thrombosis, over a short period leading to multi-system organ failure (MSOF). There is an interesting discrepancy between the prevalence and presentation. Only 1 percent of patients with APS develop severe CAPS, but almost half of all the patients with APS present with CAPS as their initial manifestations.

Unfortunately, the mechanism of this "thrombotic storm" is still not very well understood. It has been proposed that patients with CAPS may have antiphospholipid antibodies (aPL) with different antigen specificity, avidity, titer, or other features that differ from the aPL in APS causing generalized thrombosis all the body, due to the fact that patients with CAPS have triple aPL positivity with high titer immunoglobulin G (IgG) anticardiolipin and anti-beta2GPI antibodies.

#rheumatology

#hematology

References:

1. Cervera R, Bucciarelli S, Plasín MA, et al. Catastrophic antiphospholipid syndrome (CAPS): descriptive analysis of a series of 280 patients from the "CAPS Registry". J Autoimmun 2009; 32:240.

2. McNeil HP, Simpson RJ, Chesterman CN, Krilis SA. Anti-phospholipid antibodies are directed against a complex antigen that includes a lipid-binding inhibitor of coagulation: beta 2-glycoprotein I (apolipoprotein H). Proc Natl Acad Sci U S A 1990; 87:4120.

3. Ortona E, Capozzi A, Colasanti T, et al. Vimentin/cardiolipin complex as a new antigenic target of the antiphospholipid syndrome. Blood 2010; 116:2960.

4. Kitchens CS, Erkan D, Brandão LR, et al. Thrombotic storm revisited: preliminary diagnostic criteria suggested by the thrombotic storm study group. Am J Med 2011; 124:290.