Test your knowledge on haemophilia B

Haemophilia B accounts for about 15–20% of all haemophilia cases; haemophilia A is more common. 

Haemophilia B is caused by a deficiency or dysfunction of factor IX (9), not factor VIII (8). 

Haemophilia B was first described in a patient named Stephen Christmas in 1952, hence the name “Christmas disease.” 

Women can be affected by haemophilia B and haemophilia A if they inherit the condition on both their X chromosomes, meaning from both parents. Females who inherit it from one parent (carriers of haemophilia) may also have symptoms if their body uses the affected X chromosome more than the healthy one.

If you have haemophilia B or haemophilia A, you will have what is called a “bleeding tendency”. This means you are likely to bleed more often than other people.

Severity of symptoms in general depends on factor IX activity levels — mild (over 5%), moderate (1–5%), or severe (under 1%).  While severity generally correlates with factor IX activity levels, some individuals with moderate haemophilia may experience severe bleeding.

Regular and appropriate exercise helps people with haemophilia B and haemophilia A strengthen muscles and protect joints. Activities should be guided by the healthcare team. 

Treatment often involves factor IX replacement therapy. Other treatment options are non-factor-therapy or gene therapy, depending on individual needs, medical advice, and age.

Recurrent bleeding into joints (especially knees, elbows, and ankles) is typical for haemophilia B and for haemophilia A and can lead to arthropathy. 

Some carriers of haemophilia experience bleeding problems similar to males; in addition, they may experience problems that are specific to women, such as prolonged or heavy menstrual bleeding.

Genetic testing identifies mutations in the F9 gene, confirming diagnosis of haemophilia B and carrier status. 

Haemophilia B and haemophilia A occurs worldwide and affects people of all ethnic backgrounds.

Emotional wellbeing plays an important role — stress can make it harder to follow haemophilia treatment routines.

Physiotherapy is an essential adjunct to therapy for people living with haemophilia B and haemophilia A.

It is important for people with haemophilia B and haemophilia A to maintain good oral health and prevent oral diseases to avoid invasive dental procedures.

Living with haemophilia can cause stress or anxiety, but support groups and counselling can help to manage this.

Factor IX doesn’t just stay in the bloodstream, it also moves into tissues, into the “extravascular space”. 

“Extravascular” means outside the blood vessels, in areas like tissues and joints.