Three shades of black - secondary thrombotic microangiopathy.

Thrombotic microangiopathy is a group of disorders characterized by microangiopathic hemolytic anemia, thrombocytopenia and organ damage. Wide age distribution and the heterogeneity in presentation demand a deeper understanding into the pathogenesis of TMA. Primary TMA is distinct from TMA associated with secondary causes and remains clinically occult till a precipitating factor aggravates it. The extent and severity of renal damage caused by each of them is also distinct. The first alerting signal could be the presence of schistiocytes on peripheral smear and arteriolar thrombi on light microscopy. Thus in secondary TMA, identification of the underlying disorder is indispensible for targeted management.