FH and atypical hemolytic-uremic syndrome: Mutations in FH, mainly in the carboxy-terminus of the protein can lead to an ineffective local regulation of the complement system on host cells causing damage of tissues, especially on endothelia, and lead to microangiopathic hemolytic anemia and acute renal failure known as atypical hemolytic uremic syndrome (aHUS) (Józsi et al., 2005).