Elevated Von Willebrand factor propeptide for the diagnosis of thrombotic microangiopathy and for predicting a poor outcome.

Thrombotic microangiopathy (TMA) is associated with vascular endothelial cell injury and is sometimes linked with poor outcome. Von Willebrand factor (VWF) propeptide (VWFpp) is considered to be a marker of vascular endothelial cell injury. The plasma levels of VWF, VWFpp, and thrombomodulin (TM) were evaluated for their use in the diagnosis of TMA in 75 patients with TMA. There were 30 TMA patients with marked decreases in ADAMTS13 (TMA/ADAMTS13) and 45 without the decrease (TMA/other). The plasma levels of TM, VWF, and VWFpp values were significantly high in patients with TMA, especially TMA/other group. The plasma levels of TM and VWFpp were significantly high in non-survivor with TMA. In the TMA/other group, the plasma levels of VWFpp were negatively correlated with ADAMTS13 activity. The plasma levels of TM correlated with the renal function, but the plasma levels of VWFpp did not. A ROC analysis indicated that VWFpp and TM were useful markers for the prediction of a poor outcome. These findings suggest that VWFpp is an useful marker for the diagnosis of TMA and for the prediction of poor outcome.