Hemolytic uremic syndromes are microvascular occlusive disorders characterized by a mechanical hemolytic anemia, thrombocytopenia and acute kidney injury. Atypical hemolytic uremic syndrome (aHUS) is a thrombotic microangiopathy not usually associated with prodromal diarrhea, which generally results from an infectious cause.  aHUS is associated with mutations in several genes involved in the activation or regulation of the alternative complement pathway (AP).  aHUS may also be associated with autoantibodies directed against products of certain deleted or rearranged AP genes.  Mutations in the AP genes display incomplete penetrance and variable expressivity.   Individuals with a mutation in an AP gene have approximately 50% chance of developing atypical hemolytic uremic syndrome.  Other factors, such as pregnancy, exposure to certain medication, and infections, may trigger development of disease. Additionally, individuals with mutations in more than one AP gene are typically at higher risk for developing disease. A form of hemolytic uremic syndrome, also termed Nephrotic syndrome type 7, is caused by mutations in the DGKE gene.  A related disorder, thrombotic thrombocytopenia purpura, is caused by mutations in the ADAMTS13 genes. Hemolytic uremic syndrome may also be a component of methylmalonic aciduria and homocystinuria, cblC type, a disorder of cobalamin metabolism.  This later inborn error of metabolism is caused by mutations in the MMACHC gene.

Connective Tissue Gene Tests Atypical hemolytic uremic syndrome and related disorders NGS panel consists of thirteen genes: ADAMTS13, C3, CD46, CFB, CFH, CFHR1, CFHR2, CFHR3, CFHR5, CFI, DGKE, MMACHC and THBD.

Copy number variation (CNV) analysis of the Atypical hemolytic uremic syndrome susceptibility genes is also offered as a panel. Additionally, CTGT offers a comprehensive test (both NGS and CNV panels) for these genes. Panel genes are also offered as individual sequencing and deletion/duplication tests unless otherwise indicated.