ADAMTS13 and chronic kidney disease: Patients with CKD also presented elevated plasma levels of VWF, ADAMTS13 antigen, ADAMTS13 activity, D-Dimer and VWF/ADAMTS13 activity ratio, and a reduced ADAMTS13 activity/antigen ratio than those without nephropathy (P < 0.001, P < 0.001, P = 0.003, P < 0.001, P = 0.006, and P < 0.001, resp).