Functional C1-inhibitor diagnostics in hereditary angioedema: Assay evaluation and recommendations

Research output: Contribution to journalArticle


Hereditary angioedema (HAE) is an autosomal dominant disease characterized by recurrent episodes of potentially life-threatening angioedema. The most widespread underlying genetic deficiency is a heterozygous deficiency of the serine protease inhibitor Cl esterase inhibitor (C1-Inh). In addition to low C4 levels, the most important laboratory parameter for correct diagnosis of HAE or angioedema due to acquired C1-Inh deficiency is reduced C1-Inh function (fC1-Inh). No direct recommendations about the assays for fC1-Inh or sample handling conditions are available, although this would prove especially useful when a laboratory first starts to offer assays on fC1-Inh for HAE diagnosis. In the present study we evaluated the performance of fC1-Inh assays in the 15 different laboratories that are specialised in HAE diagnostics and assessed inter-laboratory variation with each laboratory using their own assays and standards. A double-blind survey was conducted using plasma/serum samples from healthy donors and HAE patients and the uniformity of HAE diagnosis was evaluated. It can be concluded that the diagnosis of fC1-Inh deficiency was made correctly inmost cases in this survey. We can recommend the chromogenic assay for the determination of fC1-Inh, while the complex ELISA needs further investigation. (C) 2008 Elsevier B.V. All rights reserved.


  • Ineke G. A. Wagenaar-Bos
  • Christian Drouet
  • Emel Aygoeren-Pursun
  • Konrad Bork
  • Christoph Bucher
  • Anette Bygum
  • Henriette Farkas
  • George Fust
  • Hanna Gregorek
  • C. Erik Hack
  • Alaco Hickey
  • Helen I. Joller-Jemelka
  • Maria Kapusta
  • Wolfhart Kreuz
  • Hilary Longhurst
  • Margarita Lopez-Trascasa
  • Kazimierz Madalinski
  • Jerzy Naskalski
  • Ed Nieuwenhuys
  • Denise Ponard
  • Lilian Varga
  • Erik Waage Nielsen
  • Eric Wagner
  • Lorenza Zingale
  • Marco Cicardi
  • S. Marieke van Ham
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Immunology in the medical area


  • complement, C1-inhibitor, hereditary angioedema, diagnostics
Original languageEnglish
Pages (from-to)14-20
JournalJournal of Immunological Methods
Issue number1-2
Publication statusPublished - 2008
Publication categoryResearch