Dermatologic Manifestations in the Antiphospholipid Syndrome

Skin manifestations are very frequent in the antiphospholipid syndrome (APS) and may be the presenting symptom of the disease. Taking into account the impact of early diagnosis on APS outcome, recognition and interpretation of these skin manifestations is paramount. Most skin lesions are the result of blood-flow impairment in the skin microvascular system. Livedo reticularis, livedo racemosa, retiform purpura and livedoid vasculopathy are frequent manifestations of the disease. Although all these terms are used to describe net-like-pattern vascular lesions, their clinical distinction is important because of the different clinical implications of each. APS may present skin lesions very similar to those of Degos' disease; however, it remains unclear how many patients with this rare vasooclusive disease present antiphospholipid antibodies (aPL). Although numerous case reports have emphasized the strong association between primary anetoderma, which is characterized by the loss of the dermal elastic fibers, and aPL, this condition seems to be a rare finding in APS. Nonetheless, many authors consider it mandatory to seek underlying aPL in patients presenting with primary anetoderma. Patients with APS may also present unspecific skin manifestations, such as superficial thrombophlebitis and post-phlebitic ulcers, due to the involvement of the venous territory. Thrombocytopenic purpura has been detected in some cases and seems to be more frequent in the SLE-related APS subset. Dermographism and chronic urticaria have been related to APS, with suspicion of an autoimmune origin. However, the potential relationship between chronic autoimmune urticaria and APS needs further confirmation and should be specifically analyzed in future studies on skin manifestations in APS.