Thrombotic thrombocytopenic purpura--the role of ADAMTS13 assay in clinical practice.

ABSTRACT

Thrombotic thrombocytopenic purpura (TTP) is a disorder characterized by disseminated thrombotic occlusions of the microcirculation. Identification of ADAMTS13 protease and its place in the pathophysiology of TTP led to better understanding of the disease and better survival for the diseased. Here we show a case report of a patient that had a normal ADAMTS13protease activity and an unusual clinical presentation and utilize that case to highlight how the absence of a severe ADAMTS13 protease deficiency does not preclude a diagnosis of TTP and how early initiation and continuation of plasma exchange therapy can lead to a positive outcome, even in a severely ill patient. Even though ADAMTS13 protease determination has no immediate influence on the decision whether or not to start the plasma exchange therapy, it has great impact on future management of the patient and should be determined whenever possible.