title: Atypical hemolytic uremic syndrome and thrombotic thrombocytopenic purpura: clinically differentiating the thrombotic microangiopathies.
abstract: The increased understanding of the pathophysiology of both atypical hemolytic uremic syndrome (aHUS) and thrombotic thrombocytopenic purpura (TTP) in recent years has led to significant therapeutic advances for both conditions. These advances have placed an increased emphasis on a more rapid differentiation of both disorders which remain clinical diagnoses. In particular, recent data demonstrating the effectiveness of complement inhibition in patients with aHUS have increased the need for a more rapid and accurate differentiation of aHUS and TTP. Previously utilized criteria have used the presence or absence of neurologic or renal injury and the pretreatment ADAMTS13 activity to differentiate aHUS from TTP. The use of presenting clinical symptoms and findings alone to differentiate these conditions is problematic given their overlapping clinical presentations. Similarly, the use of the pretreatment ADAMTS13 activity alone to differentiate aHUS from TTP is also problematic, and could lead to the inappropriate witholding of plasma exchange (PEX) therapy. However, when used collectively, the pretreatment clinical findings (symptoms and laboratory data) and ADAMTS13 activity in the context of the patient's response to PEX therapy can allow for a more effective differentiation of these two disorders in a timely fashion that will allow for the prompt initiation of the most appropriate therapy.
authors.affiliation: Department of Medicine, Ohio State University, Columbus, OH, USA. spero.cataland@osumc.edu
authors.forename: Spero R
authors.initials: SR
authors.lastname: Cataland
authors.forename: Haifeng M
authors.initials: HM
authors.lastname: Wu
mesh_terms: D051722:ADAM Proteins / Q000502:physiology; D000071120:ADAMTS13 Protein; D065766:Atypical Hemolytic Uremic Syndrome; D003167:Complement Activation; D051056:Complement Inactivating Agents / Q000627:therapeutic use; D003937:Diagnosis, Differential; D006463:Hemolytic-Uremic Syndrome / Q000175:diagnosis* / Q000201:enzymology / Q000628:therapy; D006801:Humans; D010951:Plasma Exchange; D011697:Purpura, Thrombotic Thrombocytopenic / Q000175:diagnosis* / Q000201:enzymology / Q000628:therapy
chemical_list: D051056:Complement Inactivating Agents; D051722:ADAM Proteins; D000071120:ADAMTS13 Protein; C099604:ADAMTS13 protein, human
keywords: ADAMTS13 activity; Complement activation; TTP; Thrombotic microangiopathy; aHUS