ADAMTS13 Testing During Clinical Remission of Immune Thrombotic Thrombocytopenic Purpura: A Critical Review

Immune thrombotic thrombocytopenic purpura (iTTP), an autoimmune disorder characterised by thrombocytopenia and microangiopathic haemolytic anaemia, is associated with significant morbidity. The diagnosis is made when ADAMTS13 activity is <10% in conjunction with supporting clinical features. Treatment includes plasma exchange with immunosuppressive and anti-von Willebrand factor therapies. While diagnosis and management of acute iTTP are well established, our understanding of optimal monitoring during clinical remission remains incomplete. Clinical relapse of iTTP occurs most commonly within the first year of remission, however, there is little consensus as to the frequency of ADAMTS13 monitoring during clinical remission and when to intervene when there is ongoing deficiency. Through selecting studies that performed ADAMTS13 activity testing during clinical remission of iTTP we critically analyse the current research of ADAMTS13 monitoring during clinical remission and suggest areas for further research with a focus on clinically important outcomes.