Thrombotic thrombocytopenic purpura as an initial presentation of systemic lupus erythematosus with acquired ADAMTS 13 antibody.

We report a female patient presenting with headache, fatigue, ecchymoses and recent, excessive vaginal bleeding. Prompt review of the peripheral blood smear showed evidence of microangiopathic haemolytic anaemia (MAHA) and thrombocytopenia. Thrombotic thrombocytopenic purpura (TTP) was suspected. Plasma exchange and corticosteroids were started urgently. The patient responded favourably to the treatment. Subsequently, positive serological markers returned and were compatible with systemic lupus erythematosus (SLE). A disintegrin and metalloproteinase with thrombospondin type 1 motifs, member 13 (ADAMTS 13) activity was remarkably low with a positive inhibitory ADAMTS 13 antibody. Mycophenolate and hydroxychloroquine were started along with a prolonged course and taper of corticosteroids. These medications have been maintained with an excellent response in 14 months of follow-up. 2015 BMJ Publishing Group Ltd.