The physiopathology of the catastrophic antiphospholipid (Asherson's) syndrome: compelling evidence.

Catastrophic antiphospholipid (Asherson's) syndrome (cAPS) was described in the past as a severe variant of the antiphospholipid syndrome (APS). Currently growing evidence suggests it is a unique condition. This statement is based on several clinical and physiopathological features that although not well understood define cAPS by itself. The remarkable features of cAPS are the presence of antiphospholipid antibodies (aPLAs) and microthromboses. Additional physiopathological features are the presence of anemia and thrombocytopenia, which are also often described in similar autoimmune conditions. A strong association with concomitant infection is thought to act as the main trigger of microthromboses in cAPS. Several theories have been proposed to explain these physiopathological features. Some of them suggest the possibility of molecular mimicry between components of infectious microorganisms and natural anticoagulants, which might be involved in the production of cross-reacting aPLAs in cAPS. Some genetic risk factors have also been suggested to be implicated in the onset of cAPS, however they have not been defined yet. Herein, we review the remarkable physiopathological features commonly described in cAPS hitherto. We concluded that although they are not completely understood, it is possible to differentiate them from similar conditions. Nevertheless further studies on these physiopathological mechanisms of the disease are needed.