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Hemophilia classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Sabawoon Mirwais, M.B.B.S, M.D.[2]Simrat Sarai, M.D. [3]

Overview

Overview

Hemophilia may be classified into three sub-types based on the lack of functional clotting factors: hemophilia A , hemophilia B, hemophilia C. It can also be divided into different categories based on the severity of the condition. Hemophilia can also be acquired in the setting of antibodies directed against the clotting factors.

Classification

Classification

  • Hemophilia may be classified into:

1. Hemophilia A: A recessive X-linked genetic disorder involving a lack of functional clotting factor VIII and representing approximately 80% of hemophilia cases.[1]
2. Hemophilia B: A recessive X-linked genetic disorder involving a lack of functional clotting factor IX and comprising approximately 20% of hemophilia cases.[1]
3. Hemophilia C: An autosomal genetic disorder involving a lack of functional clotting factor XI. This condition is not completely recessive, as heterozygous individuals also show increased bleeding.[2]
4. Acquired Hemophilia: An acquired condition resulting from autoantibodies directed against the clotting factors. This usually occurs in the setting of a malignancy.[3]

Classification Based on Severity

Severity Levels of Factor VIII

or IX in the blood

Normal (as in a person who does not have hemophilia) 50% to 100%
Mild Greater than 5% but less than 50%
Moderate 1% to 5%
Severe Less than 1%
Adapted from CDC Hemophilia Diagnosis> “CDC Hemophilia Diagnosis”.
References

References

  1. 1.0 1.1 Santagostino E, Fasulo MR (October 2013). “Hemophilia a and hemophilia B: different types of diseases?”. Semin. Thromb. Hemost. 39 (7): 697–701. doi:10.1055/s-0033-1353996. PMID 24014073.
  2. Shearin-Patterson T, Davidson E (April 2013). “Hemophilia C”. JAAPA. 26 (4): 50. PMID 23610841.
  3. Napolitano M, Siragusa S, Mancuso S, Kessler CM (January 2018). “Acquired haemophilia in cancer: A systematic and critical literature review”. Haemophilia. 24 (1): 43–56. doi:10.1111/hae.13355. PMID 28960809.
  4. “CDC Hemophilia classification”.

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