Consensus on the standardization of terminology in thrombotic thrombocytopenic purpura and related thrombotic microangiopathies.

BACKGROUND

Thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS) are two important acute conditions to diagnose. Thrombotic Microangiopathy is a broad pathophysiological process that leads to microangiopathic hemolytic anemia, thrombocytopenia and involves capillary and small vessel platelet aggregates. The most common cause being disseminated intravascular coagulation (DIC), which may be differentiated by abnormal coagulation. Clinically, a number of conditions present with microangiopathic hemolytic anemia and thrombocytopenia (MAHAT), including cancer, infection, transplantation, drugs, autoimmune disease and pre-eclampsia and HELLP (Hemolysis, Elevated Liver enzymes, Low Platelet count) syndrome in pregnancy. Despite overlapping clinical presentations, TTP and HUS have distinct pathophysiology and treatment pathways.

OBJECTIVES

Presented is a consensus document from an international working group on TTP and associated TMAs (thrombotic microangiopathies).

METHODS

The international working group has proposed definitions and terminology based on published information and consensus based recommendations.

CONCLUSION

The consensus aims to aid clinical decisions but also future studies and trials, utilizing standardized definitions. It presents classification of the causes of TMA, and criteria for clinical response, remission and relapse of congenital and immune mediated TTP. This article is protected by copyright. All rights reserved.