Related Experiment Videos
Autosomal recessive inheritance of von Willebrand factor-cleaving protease deficiency
D M te Loo1, E Levtchenko, M Furlan
1Department of Pediatrics, University Hospital Nijmegen, The Netherlands.
A child with chronic relapsing thrombotic thrombocytopenic purpura (TTP/HUS) had recurrent thrombocytopenia, microangiopathic hemolytic anemia with fragmented erythrocytes, microthrombi in the lung vessels, and renal dysfunction. Assay of von Willebrand factor (vWF)-cleaving protease showed a complete protease deficiency in the patient and subnormal activities in the mother and in two asymptomatic siblings. No inhibitor of vWF-cleaving protease was detected in the patient's plasma. Periodic transfusions of fresh-frozen plasma prevented further acute episodes of TTP/HUS. Specific diagnosis of the constitutional deficiency of vWF-cleaving protease helps to provide successful prophylactic therapy.
A child with chronic relapsing thrombotic thrombocytopenic purpura (TTP/HUS) had recurrent thrombocytopenia, microangiopathic hemolytic anemia with fragmented erythrocytes, microthrombi in the lung vessels, and renal dysfunction. Assay of von Willebrand factor (vWF)-cleaving protease showed a complete protease deficiency in the patient and subnormal activities in the mother and in two asymptomatic siblings. No inhibitor of vWF-cleaving protease was detected in the patient's plasma. Periodic transfusions of fresh-frozen plasma prevented further acute episodes of TTP/HUS. Specific diagnosis of the constitutional deficiency of vWF-cleaving protease helps to provide successful prophylactic therapy.