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Updated: Jul 4, 2026
06:29
Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
Complement and the atypical hemolytic uremic syndrome in children
Chantal Loirat1, Marina Noris, Véronique Fremeaux-Bacchi
1Hôpitaux de Paris, Université Paris 7, Hôpital Robert Debré, Pediatric Nephrology, Paris, France. chantal.loirat@rdb.aphp.fr
Pediatric Nephrology (Berlin, Germany)
|July 3, 2008
Summary
Atypical hemolytic uremic syndrome (aHUS) involves complement alternative pathway dysregulation. Genetic mutations in complement proteins like factor H, MCP, and factor I are common, influencing disease onset, prognosis, and treatment response.
Area of Science:
- Nephrology
- Immunology
- Genetics
Background:
- Atypical hemolytic uremic syndrome (aHUS) is linked to complement alternative pathway dysregulation.
- Genetic mutations in complement regulatory proteins (factor H, MCP, factor I) are found in 50% of pediatric aHUS cases.
- Factor H dysfunction due to autoantibodies affects 10% of children with aHUS.
Purpose of the Study:
- To analyze the genetic basis of aHUS in children.
- To correlate specific genetic mutations with clinical presentation, disease course, and treatment outcomes.
- To evaluate the efficacy of plasmatherapy and explore novel therapeutic strategies.
Main Methods:
- Literature review of approximately 200 pediatric aHUS cases.
- Analysis of mutations in complement regulatory genes (factor H, MCP, factor I, factor B, C3).
- Correlation of genetic findings with patient age, C3 levels, prognosis, and response to plasmatherapy.
Main Results:
- Factor H and factor I mutations are associated with early-onset aHUS; MCP mutations appear after age 1.
- Low C3 levels suggest factor H or I mutations, while normal C3 may indicate MCP mutations.
- Factor H mutations carry the worst prognosis (60% mortality/ESRD within 1 year); MCP mutations have a relapsing course without early ESRD.
Conclusions:
- Genetic analysis is crucial for understanding aHUS heterogeneity and predicting outcomes.
- Plasmatherapy is beneficial except in MCP-mutated aHUS; liver transplantation is an option for certain mutations.
- Targeted therapies like factor H concentrate and complement inhibitors show promise for future aHUS treatment.
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