Localized cutaneous necrosis associated with the antiphospholipid syndrome

A 34-year-old woman with systemic lupus erythematosus and high titres of antiphospholipid antibodies was admitted to hospital suffering a viral illness but developed haemorrhagic and necrotic areas on the neck and anterior chest 7 days following cessation of warfarin. Anticoagulation had been initiated following a retinal vein thrombosis, but was ceased on day 4 of admission when she was found to be excessively anticoagulated (international normalized ratio (INR) > 10). However, at the time of developing the cutaneous lesions, the INR was sub-therapeutic. Histology of a skin biopsy from the neck revealed thrombosis of upper dermal blood vessels without vasculitis, consistent with antiphospholipid antibody-related skin necrosis. This case illustrates one of the cutaneous features that can occur in patients with elevated titres of antiphospholipid antibodies and the importance of closely monitoring anticoagulation in such patients.