Table 1.

Classification (Orpha number), synonyms, prevalence and clinical description of hemophilia (Adapted from Orphanet portal [http://www.orpha.net ])

Type of hemophilia	Orpha number	Synonyms	Prevalence	Clinical description
Hemophilia (general)	448	Factor VIII or IX deficiency	7.7/100,000	Bleeding episodes.
Hemophilia A	98878	Factor VIII deficiency	1/6,000	Spontaneous or prolonged hemorrhages.
Hemophilia B	98879	Factor IX deficiency	1/30,000	Spontaneous or prolonged hemorrhages.
Mild hemophilia A	169808	Mild factor VIII deficiency	40% of all cases of hemophilia A	Small deficiency of factor VIII leading to abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor VIII is between 5 and 40%. Spontaneous hemorrhages do not occur.
Mild hemophilia B	169799	Mild factor IX deficiency	30% of all cases of hemophilia B	Small deficiency of factor IX leading to abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor IX is between 5 and 40%. Spontaneous hemorrhages do not occur.
Moderately severe hemophilia A	169805	Moderately severe factor VIII deficiency	20% of all cases of hemophilia A	Abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor VIII is between 1% and 5%. Spontaneous hemorrhages are rare.
Moderately severe hemophilia B	169796	Moderately severe factor IX deficiency	30% of all cases of hemophilia B	Abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor IX is between 1% and 5%. Spontaneous hemorrhages are rare.
Severe hemophilia A	169802	Severe factor VIII deficiency	40% of all cases of hemophilia A	Frequent spontaneous hemorrhage and abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor VIII is below 1%.
Severe hemophilia B	169793	Severe factor IX deficiency	40% of all cases of hemophilia B	Frequent spontaneous hemorrhage and abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. The biological activity of factor IX is below 1%.
Symptomatic form of hemophilia A in female carriers	177926	Hemophilia A carriers	Unknown(very rare)	In some women with mutations in the F8 gene, encoding coagulation factor VIII. Symptoms include abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. Spontaneous hemorrhages may occur occasionally. The biological activity of factor VIII is below ~30%.
Symptomatic form of hemophilia B in female carriers	177929	Hemophilia B carriers	Unknown (very rare)	In some women with mutations in the F9 gene, encoding coagulation factor IX. Symptoms include abnormal bleeding as a result of minor injuries, or following surgery or tooth extraction. Spontaneous hemorrhages may occur occasionally. The biological activity of factor IX is below ~30%.