Fig. 1.
vWF-cleaving protease activity in plasma from 111 patients with TMA as a function of the progressive form.
vWF-cleaving protease activity was measured during an acute event in 85 sporadic, 21 intermittent, and 5 familial recurrent forms of TMA. Patients were presenting as TTP (●) or HUS (○). The dashed line shows the lower limit of normal (50%).