Recurrent atypical haemolytic uraemic syndrome post kidney transplant due to aCD46mutation in the setting ofSMARCAL1-mediated inherited kidney disease

Disorders in the regulation of the alternate complement pathway often resultin complement-mediated damage to the microvascular endothelium and canbe associated with both glomerulonephritis and atypical haemolytic uraemicsyndrome. Inherited defects in complement regulatory genes or autoanti-bodies against complement regulatory proteins are predictive of the severityof the disease and the risk of recurrence post kidney transplantation. Hetero-zygous mutations in CD46, which codes for a transmembrane cofactor glyco-protein membrane cofactor protein, usually have a lower incidence of end-stage kidney disease and decreased risk of recurrent disease post transplant,as wild-type membrane cofactor protein is present in the transplanted kidney.However, some patients with CD46 mutations have a second variant in othercomplement regulatory genes increasing the severity of disease. The followingcase report illustrates the course of a young adult patient with end-stage kidneydisease initially ascribed to seronegative systemic lupus erythematosus, whopresented with biopsy-proven thrombotic microangiopathy following kidneytransplantation. It highlights the complexity associated with disorders of com-plementregulationandtheneed forahighindexofsuspicionandgenetictestingin patients who present with thrombotic microangiopathy post-transplant.

Nephrology

Nephrology

22

1440-1797

N/A

S1

4