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Normal complement C4 values do not exclude hereditary angioedema
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  • Published on:
    Does normal C4 exclude hereditary angioedema (HAE)?
    • Robert J Lock, Principal Clinical Scientist
    • Other Contributors:
      • Mark M. Gompels and Paul F.Virgo

    Dear Editor

    We read with interest the case report from Karim and colleagues in the Journal.[1] This case raises an important issue.

    Our study [2] has been quoted as suggesting that we have described HAE with normal C4. We do not entirely accept this interpretation. Although there were HAE patients with normal C4 this was only achieved whilst on adequate treatment. All 20 HAE patients in whom we were able...

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    Conflict of Interest:
    None declared.