Thrombotic Microangiopathies: Classification and Differential Diagnosis

Abstract

Thrombotic microangiopathies (TMA) are a group of clinical conditions mainly characterized by low platelet count, hemolytic anemia and organ damage. TMA can be acquired or hereditary and classified according to their etiology. Both males and females can be affected although different prevalence in age is observed and related to the subgroup. Hyperactivation of the alternative pathway of complement cascade, independently from its etiology, is accountable for microvascular thrombosis and its related clinical manifestations. The onset of TMA is often aggressive and it can be difficult to make an early correct differential diagnosis. It is crucial to perform specific tests at clinical presentation to help the clinician in making the diagnosis and to begin a better and more specific treatment. Research of genetic mutations is helpful to identify genetic TMA, sporadic or familiar, but not for the diagnosis at clinical onset. Because of TMA rarity, patients should be promptly sent to the attention of hematologists. New approaches on diagnosis and therapies have improved the prognosis of TMA especially in adults but further studies are needed.