Abstract
Thrombotic microangiopathy (TMA) is characterized by the presence of microangiopathic
hemolytic anemia and thrombocytopenia. There are several disorders with varied etiopathogenesis,
both genetic and acquired, that result in TMA. The neutrophils play an important role
in inflammation and thrombosis through the formation of neutrophil extracellular traps
(NETs). NETs are formed in response to a variety of stimuli including infections,
chemical factors, and platelet activation. The classic TMA, thrombotic thrombocytopenic
purpura (TTP) is caused by a severe deficiency of ADAMTS-13 (a disintegrin and metalloproteinase
with a thrombospondin type-I motif, member 13), mostly acquired due to autoantibodies,
whereas atypical hemolytic uremic syndrome (aHUS) is mostly attributed to genetic
defects in complement pathway regulatory proteins. The management of these well-known
disorders has evolved over the last decade. Similarly, there is also better understanding
of diverse and unusual clinical presentations of both of these conditions. Since there
are many other causes of TMAs, which may mimic some of the clinical features of TTP
or aHUS, it is essential to thoroughly investigate each patient so that appropriate
therapy can be offered. This review focuses on some important developments in understanding
of etiopathogenesis, diagnosis, and treatment of more commonly encountered TMAs.
Keywords
ADAMTS-13 - complement - endothelium - hemolytic uremic syndrome - neutrophils - microangiopathic
hemolytic anemia - thrombocytopenia - thrombotic microangiopathy - thrombotic thrombocytopenic
purpura
