The disease known as hemophilia was mentioned in written records as early as 2000 years ago.  By the fifth century A.D. hemophilia was recognized as an inherited disease that affects mostly males.  The transmission of hemophilia from carrier mothers to their sons was first described in the United States in 1803.  The presence of the disease among members of many European royal families during the 19th and 20th centuries originated with Queen Victoria, a carrier whose descendants introduced the disorder to the royal houses of Russia, Germany and Spain.  In the 1980’s, hemophilia made the headlines as one the first human disorders in which the responsible gene was identified and cloned.

Cause

There are more than  ten substances in the blood, called clotting factors that must work in a specific sequence to produce blood clotting.  An abnormality in any of these factors can lead to bleeding problems.  Hemophilia is caused by a defect or deficiency in either of two clotting substances: factor VIII, which causes hemophilia A, or factor IX, which causes hemophilia B.  About 15,000 to 20,000 people in the U.S. have hemophilia.  Hemophilia occurs in 1 in 5,000 live male births.  Defects or deficiencies in other blood factors, such as factors I, II, VII, X, XI and XIII, cause other coagulation disorders, all of them much rarer than hemophilia A and B.

Besides hemophilia, there are a number of other inherited bleeding disorders.  Chief among these is von Willebrand disease which affects about 1.3 million people in the U.S., both male and female.  Von Willebrand disease is not considered a rare disorder.

Inheritance

About one-third of individuals affected develop  hemophilia through a spontaneous gene mutation.  This means that they were born to women with no history of hemophilia in their families.  In some extremely rare cases, hemophilia may occur in women.

Severity

In severe hemophilia, the clotting factor activity is less than 1 percent of the normal range.  In addition to prolonged bleeding due to injury or surgery, spontaneous internal bleeding may occur in parts of the body such as joints, muscles, and sometimes, the head.  This can cause stroke or damage to internal organs such as, joints or muscles.  In moderate hemophilia, clotting activity is between 1 and 5 percent of the normal range.  Spontaneous bleeding does not usually occur, but minor injury may cause prolong bleeding.  In mild hemophilia, clotting activity is  above 5 percent.  Bleeding usually only occurs as a result of trauma, surgery, or invasive dental procedures.

Treatment

Treatment consists of replacing the deficient clotting factor by the intravenous infusion of highly purified factor derived from human blood.  Synthetic (recombinant) factors , though expensive, have become the treatment of choice and the standard of care.

These products are produced in the laboratory, without the use of human blood. In the 1970s, the advent of concentrated clotting factor enabled people with hemophilia to infuse themselves at home.  Many patients take prophylactic doses of  the factor two to three days a week to prevent and protect their joints.  Mild hemophiliacs may respond to other medications such as DDAVP which is available in an intravenous and nasal spray form.