The Japanese experience with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome. Matsumoto M, Yagi H, Ishizashi H, Wada H, Fujimura Y. Seminars in Hematolology 2004;41(1):68-74.

ABSTRACT:

A total of 290 Japanese patients with thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS) were analyzed with respect to ADAMTS-13 activity and its inhibitor. Twenty-one patients (17 families) had Upshaw-Schulman syndrome, and 12 patients (six families) had familial HUS of undetermined etiology. The number of patients with acquired HUS and TTP was 44 and 213, respectively. Of the 44 acquired HUS cases, 10 were secondary; seven of these ten were associated with E. coli O157:H7 infection. None of the acquired HUS cases had a severe deficiency of ADAMTS-13 activity, five showed moderately decreased activity, 24 had mildly decreased activity , and 15 were normal. No inhibitor of ADAMTS-13 activity was detected in any of these patients. In acquired TTP, patients with severe deficiency of ADAMTS-13 activity secondary to the presence of an inhibitor were high responders to plasma exchange (PE), but others were low responders to PE. The former patients were associated with idiopathic TTP, drugs, and pregnancy, and the latter patients with malignancy and stem cell transplantation. Patients with autoimmune disease-associated TTP fit into both groups. One 9-month old infant had high titers of inhibitor against ADAMTS-13. She had diarrhea associated with Rota virus infection on admission, but its relationship with TTP was unclear; she was categorized as having idiopathic TTP. Soon after admission she was in critical condition, but after receiving extensive plasma exchange therapy and steroid pulse therapy, she completely recovered.