Of the 36 patients with acquired ADAMTS13 deficiency, TTP was considered SLE-related in 10, Sjögren’s syndrome-related in three, undifferentiated connective tissue disease (UCTD)-related in two, malignancy-related in three, and primary in 18 patients (Fig. 1). Here, ADAMTS13 is linked to thrombotic thrombocytopenic purpura.