Factor VII deficiency: living with a rare clotting disorder

GOSH explains that blood clotting works through a series of clotting proteins, or coagulation factors, switched on in a strict order. When a vessel is injured, platelets clump together and a complicated chemical reaction forms a mesh of fibrin that stops the bleeding. If any factor is missing, blood loss can be severe and life-threatening. In factor VII deficiency, which GOSH says is also known as Alexander's disease, the missing or reduced factor is factor VII.

GOSH describes two types. In type 1 factor VII is absent or low in the blood. In type 2 it is present but does not work properly. In both, severity ranges from mild to severe depending on the amount of factor VII and its activity.

The Haemophilia Society lists the rare bleeding disorders on its website, and Guy's and St Thomas' NHS Foundation Trust includes factor VII deficiency among conditions that are very rare, usually inherited, able to affect males and females and range from mild to severe.

GOSH says factor VII deficiency is caused by a mutation on the F7 gene inherited in an autosomal recessive manner, which means a person has to inherit the faulty gene from both parents to develop the disease. Each pregnancy of two carrier parents carries a 75 per cent chance of an unaffected child and a 25 per cent chance of an affected child.

Carriers, with one copy of the faulty gene, are mostly healthy, although GOSH says occasionally affected carriers may show very mild symptoms that may or may not need treatment. Genetic counselling is available before planning a family, for affected people and unaffected carriers alike.

GOSH says the age at which symptoms appear depends on how much factor VII is present and how well it works. Children with little or none may show symptoms soon after birth, whereas those with some working factor VII may not show symptoms until later, often following surgery or injury. People with severe deficiency can bleed more severely after injury or for longer. Bleeding can happen inside the body as well as from the skin, including bleeds into the joints. Mouth bleeds after dental work, heavy periods and blood loss during childbirth also occur.

In babies, GOSH says a clotting disorder may be suspected after a bleed inside the brain (intracranial haemorrhage) or if bleeding continues after the umbilical cord is cut or after surgery such as circumcision. In older children and adults, suspicion may arise from bruising or bleeding, or from routine checks before an operation or after an injury.

GOSH says factor VII deficiency is diagnosed with a blood sample tested in a laboratory. A test of how long the sample takes to clot may suggest a clotting disorder, which is investigated further. The level of factor VII is checked and doctors will try to identify the gene mutation, which helps plan for future siblings and test other family members. Imaging such as MRI, CT or ultrasound may be used to look for internal bleeds, for example in a joint.

With a family history, prenatal diagnosis is possible by chorionic villus sampling early in pregnancy or amniocentesis at around 15 to 20 weeks. Guy's and St Thomas' adds that people are often diagnosed later in life, for example after unexpected heavy bleeding during surgery or dental extractions, and that affected women may be identified because of heavy periods or bleeding in childbirth.

GOSH says that if symptoms are not problematic or the level of factor VII is only mildly reduced, treatment may not be needed. In many cases treatment is given on demand, to treat symptoms as they occur, rather than as regular preventative treatment. When treatment is given it aims to replace the missing or reduced factor VII with a man-made substitute given as an injection.

Guy's and St Thomas' says treatment of rare bleeding disorders is usually needed only occasionally, for troublesome bleeding or to prevent excessive bleeding with surgery, invasive procedures, dental work or childbirth, that tranexamic acid can be given as a tablet or into the vein, and that recombinant factor VIIa is among the factor concentrates used. In very rare severe cases, regular treatment might be given.

People with factor VII deficiency should avoid NSAIDs such as ibuprofen, according to GOSH, and use other forms of pain relief. Immunisations should be given under the skin rather than into a muscle.

GOSH says children and young people have a normal life span. Contact sports with a high risk of head injury may need to be avoided, but most day-to-day activities cause few problems. A medical alert necklace or bracelet is advised, and surgery or pregnancy needs careful planning with all professionals aware. Regular specialist reviews usually include a physiotherapist and dentist, and young people are supported to move on to adult services.

A general point from Guy's and St Thomas': mild forms usually do not cause everyday bleeding problems. Many people therefore carry on without treatment, and the plan is mainly about being ready for situations such as dental work, operations and childbirth.

In the NHS, diagnosis and treatment are provided through haemophilia centres, with haematology referral from a GP or dentist when unexplained bleeding is found. The Haemophilia Society provides information. Private haematology can be used for assessment, but a plan for procedures such as surgery, dental extractions and childbirth is best made with the specialist centre that holds your records and treatment products.