Complement factor H functional assay may help to monitor atypical haemolytic uraemic syndrome: a pilot study

Annick Massart, Said Hachimi-Idrissi, Emine Broeders, Y Tournay, Joelle Nortier, Daniel Abramowicz, Christian Tielemans, Patrick Stordeur

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2 Citations (Scopus)


Background: Atypical haemolytic uraemic syndrome (aHUS) results from uncontrolled complement system activation. Complement factor H gene mutations are common causes of aHUS. Plasmatherapy, including plasma infusions and/or plasma exchanges, has been tried in this Setting with various successes. At present, we lack a specific marker to monitor functional factor H deficiency-related aHUS.

Methods: We report the use of factor H functional assay in three patients-with atypical haemolytic uraemic syndrome. This assay is based on the requirement of soluble complement regulators that bind sheep red cells to prevent haemolysis. As factor H is highly abundant in the plasma, its defect results in haemolysis. Factor H activity was also measured among plasma donors.

Results: One patient suffered from a plasma-dependent form of atypical haemolytic uraemic,syndrome, Plasma exchanges restored higher factor H activity-and were associated With a 15-months-disease-free period. In the two other patient, one With-a failing renal graft and the-other-on chronic dialysis,,a bout of thrombotic micro-angiopathy was preceded by a drop of haemolytic activity below normal values. Plasma from healthy donors (N = 65) showed only minimal variations of Factor H activity (mean activity: 98.3%, SD=4.0).

Conclusion: These preliminary data suggest that factor H activity could be of interest in both the diagnosis and the treatment by plasmatherapy of factor H-related aHUS.
Original languageDutch
Pages (from-to)9-14
Number of pages6
JournalActa Clinica Belgica
Publication statusPublished - Jan 2013


  • Atypical Haemolytic Uraemic Syndrome
  • Complement Factor H

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