Differential impact of complement mutations on clinical characteristics in atypical hemolytic uremic syndrome.
Mutations in factor H (CFH), factor I (IF), and membrane cofactor protein (MCP) genes have been described as risk factors for atypical hemolytic uremic syndrome (aHUS). This study analyzed the impact of complement mutations on the outcome of 46 children with aHUS. A total of 52% of patients had mutations in one or two of known susceptibility factors (22, 13, and 15% of patients with CFH, IF, or MCP mutations, respectively; 2% with CFH+IF mutations). Age <3 mo at onset seems to be characteristic of CFH and IF mutation-associated aHUS. The most severe prognosis was in the CFH mutation group, 60% of whom reached ESRD or died within <1 yr. Only 30% of CFH mutations were localized in SCR20. MCP mutation-associated HUS has a relapsing course, but none of the children reached ESRD at 1 yr. Half of patients with IF mutation had a rapid evolution to ESRD, and half recovered. Plasmatherapy seemed to have a beneficial effect in one third of patients from all groups except for the MCP mutation group. Only eight (33%) of 24 kidney transplantations that were performed in 15 patients were successful. Graft failures were due to early graft thrombosis (50%) or HUS recurrence. In conclusion, outcome of HUS in patients with CFH mutation is catastrophic, and posttransplantation outcome is poor in all groups except for the MCP mutation group. New therapies are urgently needed, and further research should elucidate the unexplained HUS group.
Sellier-Leclerc
Anne-Laure
AL
Service de Néphrologie, Assistance Publique-Hôpitaux de Paris, Hôpital Robert Debré, 48 Boulevard Sérurier, 75 019 Paris, France.
Fremeaux-Bacchi
Veronique
V
Dragon-Durey
Marie-Agnès
MA
Macher
Marie-Alice
MA
Niaudet
Patrick
P
Guest
Geneviève
G
Boudailliez
Bernard
B
Bouissou
François
F
Deschenes
Georges
G
Gie
Sophie
S
Tsimaratos
Michel
M
Fischbach
Michel
M
Morin
Denis
D
Nivet
Hubert
H
Alberti
Corinne
C
Loirat
Chantal
C
D017668:Age of Onset; D002648:Child; D017242:Complement Factor H / Q000235:genetics*; D005260:Female; D005340:Fibrinogen / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D006463:Hemolytic-Uremic Syndrome / Q000235:genetics* / Q000401:mortality* / Q000601:surgery; D006801:Humans; D007223:Infant; D016030:Kidney Transplantation / Q000401:mortality; D008297:Male; D051916:Membrane Cofactor Protein / Q000235:genetics*; D010949:Plasma; D017354:Point Mutation; D011183:Postoperative Complications / Q000401:mortality; D011379:Prognosis; D012307:Risk Factors; D013927:Thrombosis / Q000453:epidemiology; D016896:Treatment Outcome
C497857:CD46 protein, human; D051916:Membrane Cofactor Protein; D017242:Complement Factor H; D005340:Fibrinogen