Today with appropriate treatment, males with haemophilia typically have a near normal quality of life with an average lifespan approximately 10 years shorter than an unaffected male.Since the 1980s the primary leading cause of death of people with severe haemophilia has shifted from haemorrhage to HIV/AIDS acquired through treatment with contaminated blood products. The second leading cause of death related to severe haemophilia complications is intracranial haemorrhage which today accounts for one third of all deaths of people with haemophilia. Two other major causes of death include hepatitis infections causing cirrhosis and obstruction of air or blood flow due to soft tissue haemorrhage. Epidemiology
Haemophilia frequency is about 1 instance in every 10,000 births (or 1 in 5,000 male births) for haemophilia A and 1 in 50,000 births for haemophilia B. About 18,000 people in the United States have haemophilia. Each year in the US, about 400 babies are born with the disorder. Haemophilia usually occurs in males and less often in females. It is estimated that about 2,500 Canadians have haemophilia A, and about 500 Canadians have haemophilia B. History
Scientific discovery
The excessive bleeding was known to ancient people. The Talmud instructs that a boy must not be circumcised if he had two brothers who died due to complications arising from their circumcisions, and Maimonides says that this excluded paternal half-brothers. This may have been due to a concern about hemophilia. The first medical professional to describe the disease was Arab surgeon Al-Zahrawi, also known as Abulcasis.
However, it is possible for female carriers to become mild haemophiliacs due to lyonisation (inactivation) of the X-chromosomes. Haemophiliac daughters are more common than they once were, as improved treatments for the disease have allowed more haemophiliac males to survive to adulthood and become parents. Adult females may experience menorrhagia (heavy periods) due to the bleeding tendency. The pattern of inheritance is criss-cross type. This type of pattern is also seen in colour blindness.A mother who is a carrier has a 50% chance of passing the faulty X-chromosome to her daughter, while an affected father will always pass on the affected gene to his daughters. A son cannot inherit the defective gene from his father. Genetic testing and genetic counselling is recommended for families with haemophilia. Prenatal testing, such as amniocentesis, is available to pregnant women who may be carriers of the condition.As with all genetic disorders, it is also possible for a human to acquire it spontaneously through mutation, rather than inheriting it, because of a new mutation in one of their parents gametes. Spontaneous mutations account for about 33% of all cases of haemophilia A. About 30% of cases of haemophilia B are the result of a spontaneous gene mutation. If a female gives birth to a haemophiliac son, either the female is a carrier for the blood disorder or the haemophilia was the result of a spontaneous mutation.