Thrombotic microangiopathy: focus on atypical hemolytic uremic syndrome.

Thrombotic microangiopathies (TMA) such as atypical hemolytic uremic syndrome (aHUS) have evolved from rare, fulminant childhood afflictions to uncommon diseases with acute and chronic phases involving both children and adults. Breakthroughs in complement and coagulation regulation have allowed redefinition of specific entities despite substantial phenotypic mimicry. Reconciliation of phenotypes and delivery of life saving therapies require a multidisciplinary team of experts. The purpose of this review is to describe advances in the molecular pathophysiology of aHUS and to share the 2014 experience of the multidisciplinary Johns Hopkins TMA Registry in applying diagnostic assays, reporting disease associations, and genetic testing.