Hemophilia or haemophilia is a rare, inherited bleeding disorder in which the blood does not clot normally. People who have it may bleed for a longer period of time following an injury or accident. While the blood disorder usually occurs only in males, there are rare exceptions in which a female will have it.
Symptoms of hemophilia include bleeding (which may occur internally, especially in the joints (such as the knees, ankles, and elbows)) and bruising. Treatment most often involves replacement therapy, in which the clotting factor missing in people with the disease is replaced.
Approximately 18,000 people in the United States have hemophilia, and about 400 babies are born each year with this disorder in the U.S. Although it usually occurs only in males, there are very rare exceptions in which a female will have the blood disorder.
People with hemophilia have problems with certain proteins in their blood, called clotting factors. Clotting factors help blood to clot. Hemophilia can occur if there is a low level of one of the clotting factors or if a clotting factor is completely missing.
When clotting factors are missing, or your body does not have enough clotting factors, it can take a long time for your blood to clot after an injury or accident.
There are two main types of the disorder: hemophilia A and hemophilia B. Both types have the same symptoms. However, the two types are caused by problems with different clotting factors and have slightly different treatments.
There is also a rarer form of hemophilia called acquired hemophilia. This is not an inherited condition but is caused by the immune system (the body's natural defence against infection and illness) attacking the clotting factors in the blood.
In hemophilia A, clotting factor 8 (VIII) is low or missing. Approximately 9 out of 10 people with hemophilia have type A. In hemophilia B, clotting factor 9 (IX) is low or missing.
In hemophilia C, the person has low levels of or is missing completely factor 11 (Also called FXI or factor XI deficiency). Hemophilia C is 10 times more rare than type A. Factor XI deficiency is different because it can show up in both males and females.
Hemophilia is an inherited disease. Specifically, hemophilia is caused by mutations in the F8 or F9 genes that determines how the body makes blood clotting factors. These genes are located on the X chromosomes, which determine whether a baby is a boy or girl.
In most cases, hemophilia is passed from a female carrier to her son; however, it is possible for boys with hemophilia to be born to mothers who are not carriers when there is a random mutation in the gene as it is passed on to the child. Although it is very rare, it is possible for a girl to be born with hemophilia.
Mutations in the F8 or F9 genes cause hemophilia. Mutations in the F8 gene cause hemophilia A, while hemophilia B is caused by mutations in the F9 gene. Hemophilia C is caused by a mutation in the F11 gene.
The proteins made by these genes play a critical role in the process of blood clotting. Mutations in either gene prevent clots from forming in response to injury, which lead to excessive bleeding that can be difficult to control.
Hemophilia is inherited in an X-linked recessive pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, which is one of the two sex chromosomes.
Chromosomes come in pairs. Women have two X chromosomes, while men have one X and one Y chromosome. A woman is a "carrier" if she has a defective gene for factor 8 or factor 9 on one of her X chromosomes. She can pass the defective gene on to her children.
If she has a son, there is a 1 in 2 chance (50 percent) that he will have hemophilia.
If she has a daughter, there is a 1 in 2 chance (50 percent) that the daughter will be a carrier.
A man who has hemophilia cannot pass the disease on to his sons; however, all of his daughters will be carriers.
In very rare cases, a girl may be born with hemophilia. This can occur if her father has hemophilia and her mother is a carrier.
In some cases, boys with hemophilia are born to mothers who are not carriers. This occurs when there is a random change (mutation) in the gene as it is passed on to the child.
An injury (such as a cut) to a blood vessel causes a complex chain of events that will result in a blood clot. This is called the clotting process, which is also known as blood coagulation. Clotting is your body's reaction to bleeding to keep you from losing too much blood. Losing too much blood can be life threatening and can damage your internal organs.
Clotting factors are proteins in the blood that work with platelets -- small blood cell fragments -- to help the blood to clot. When blood vessels are damaged, clotting factors help the platelets stick together to plug cuts and breaks at the site of the injury.
In people with hemophilia, blood does not clot as it should due to missing or low levels of one of these clotting factors. If this occurs, there may be heavy blood loss or injured body tissues and organs, which can result in permanent damage or even death.
The extent of bleeding will depend on the type and severity of hemophilia a person has. Types of hemophilia include hemophilia A and hemophilia B. Severity of hemophilia symptoms may be mild, moderate, or severe. For example:
Children with very mild disease may not have noticeable hemophilia symptoms for years. Often, the first hemophilia symptom is heavy bleeding from a dental procedure, an accident, or surgery.
Children with mild to moderate disease may not have any hemophilia symptoms or signs at birth.
Boys with severe disease may bleed heavily after a cut.
Internal bleeding is a common problem for people with severe hemophilia. When internal bleeding is not treated promptly, it can lead to damaged joints, muscles, or other parts of the body.
Most people (about 7 out
of 10) with hemophilia A have severe hemophilia symptoms.
In most children, the first hemophilia symptoms often include:
Heavy bruising and bleeding from the gums as they cut their baby teeth
Bumps and bruises from frequent falls as they learn to walk
Swelling and bruising from bleeding in the joints, soft tissue, and muscles.
The most common hemophilia symptoms in older children and adults include such things as:
Bleeding in the joints, which is also known as hemarthrosis
Bleeding and bruising in the soft tissue and muscles
Bleeding in the mouth from a cut or bite or loss of a tooth
Nosebleeds for no obvious reason
Blood in the urine (from bleeding in the kidneys or bladder)
Blood in the stool (from bleeding in the intestines or stomach).
Bleeding in the joints is
the most common symptom experienced by people with severe hemophilia.
Such bleeding often occurs without an injury and can continue for
days if it is not treated. However, people with hemophilia can learn
to recognize early symptoms of bleeding in the joints and get
treatment quickly. Early hemophilia treatment can help limit damage
to the joints.
While bleeding can occur in any joint, it most often occurs in the:
Knees
Elbows
Ankles.
The symptoms of bleeding in the joints may include:
Tightness in the joint
Pain (which may occur before there are any visible signs of bleeding)
Swelling of the joint
A feeling of warmth in the affected area (The joint may be hot to the touch.)
Pain when bending or extending the joint
Loss of movement in the joint.
The bleeding will typically slow after several days when the joint is full of blood; however, if the bleeding in the joint is not treated, it can lead to disabling arthritis.
Bleeding in the brain is a serious potential complication of hemophilia that requires emergency treatment. This can be the result of a simple bump on the head or a more serious head injury. The signs and symptoms of bleeding in the brain may include:
Long-lasting painful headaches
Repeated vomiting
Extreme sleepiness
Changes in behavior
Sudden weakness or clumsiness of the arm or leg
Neck pain or stiffness
Double vision
Difficulty walking
Convulsions or seizures.
Diagnosing hemophilia usually involves a review of the patient's personal and family medical history, a physical examination, and blood tests. Once a doctor has reached a diagnosis of hemophilia, he or she will often classify the severity of the bleeding disorder as mild, moderate, or severe based on how much clotting factor is in the blood. When diagnosing hemophilia, it's important to determine whether a person has hemophilia A or hemophilia B.
While there's no cure for hemophilia, most people with the disease can lead fairly normal lives. In most cases of hemophilia, treatment involves replacing the clotting factor that is too low or missing. This is known as replacement therapy, and it can be used to prevent bleeding or to stop bleeding when it occurs. Clotting factor concentrates that are used in treating this condition may come from donated blood or from lab-produced clotting factors. Other options include a synthetic hormone known as desmopressin and antifibrinolytic drugs.
Mild hemophilia A. Treatment may involve slow injection of the hormone desmopressin (DDAVP) into a vein to stimulate a release of more clotting factor to stop bleeding. Occasionally, desmopressin is given as a nasal medication.
Moderate to severe hemophilia A or hemophilia B. Bleeding may stop only after an infusion of clotting factor derived from donated human blood or from genetically engineered products called recombinant clotting factors. Repeated infusions may be needed if internal bleeding is serious.
Hemophilia C. The clotting factor missing in this type of hemophilia (factor XI) is available only in Europe. In the U.S., plasma infusions are needed to stop bleeding episodes.
Regular preventive infusions of a clotting factor may help prevent bleeding. This approach may reduce time spent in the hospital and away from home, work or school and limit side effects such as damage to joints. Your doctor or child's doctor can train you to perform infusions of desmopressin or the clotting factor at home, work or school.
Another class of drugs called antifibrinolytics is sometimes prescribed along with clotting factor replacement therapy. These medications help prevent clots from breaking down.
If internal bleeding has damaged joints, physical therapy can help them function better. Therapy can preserve their mobility and help prevent frozen or badly deformed joints. In cases where repeated bouts of internal bleeding has damaged or destroyed joints, an artificial joint may be needed.
If you or your child experiences a small cut or scrape, using pressure and a bandage will generally take care of the bleeding. For small areas of bleeding beneath the skin, use an ice pack. Ice pops can be used to slow down minor bleeding in the mouth.
These steps may help you avoid excessive bleeding and protect your joints:
Exercise regularly. Activities such as swimming, bicycle riding and walking can build up muscles while protecting joints. Contact sports — such as football, hockey or wrestling — are not safe for people with hemophilia.
Avoid certain medications. Drugs that can aggravate bleeding include aspirin and ibuprofen (Advil, Motrin, others). Instead, use acetaminophen (Tylenol, others), which is a safe alternative for mild pain relief. Also avoid certain blood-thinning medications, such as heparin and warfarin (Coumadin), which prevent blood from clotting. Certain herbal supplements also contain ingredients that may cause bleeding, especially if you have hemophilia. Talk to your doctor before taking any herbal supplements.
Practice good dental hygiene. This can help prevent the need to have a tooth pulled, which can lead to excessive bleeding.
Protect your child from injuries that could cause bleeding. If your child has hemophilia, ask your doctor for guidance that can help your child stay active while avoiding injury. Kneepads, elbow pads, helmets and safety belts all may help prevent injuries from falls and other accidents. In addition, keep your home free of furniture with sharp corners and keep sharp objects out of reach or locked away.