Familial hemolytic uremic syndrome associated with complement factor H deficiency

Atypical hemolytic uremic syndrome (HUS) associated with factor H deficienc y (FHD) carries a poor prognosis. A 3-year-old girl with FHD-HUS reached en d-stage renal disease at age 6 months after experiencing numerous relapses; she underwent a cadaveric renal transplant at age 46 months. One month aft er transplantation, she experienced an extensive non-hemorrhagic cerebral i nfarction. Later, hematologic and renal manifestations of HUS developed, fo llowed by another massive cerebral infarction and death in spite of multipl e plasma transfusions. A 14-month-old boy with FHD-HUS experienced numerous HUS episodes starting at the age of 2 weeks. Daily plasma transfusions dur ing relapses brought about only a temporary state of remission. However, pr ophylactic tu ice-weekly plasma therapy has been successful in preventing r elapses and preserving renal function. With this regimen, serum factor H wa s increased from 6 mg/dL to subnormal values of 12 to 25 mg/dL (normal >60 mg/dL). We conclude that FHD-HUS recurs because FHD is not corrected by ren al transplantation. A hypertransfusion protocol may prevent FHD-HUS.