Factor V and Factor VIII Deficiency
What is combined factor V and VIII deficiency?
Combined factor V (5) and factor VIII (8) deficiency is an inherited bleeding disorder that is caused by low levels of factors V and VIII. This is different than just factor V deficiency or factor VIII deficiency (hemophilia A). Stable blood clots do not form if you are missing or have too little of both of these factors.
In contrast to either factor V or factor VIII deficiency, the problem is not that you make little or no factor V or VIII. The problem is that you can’t get the factor you make into the bloodstream. The proteins (factors V and VIII) are not able to be transported out of the cells that make them.
According to an international organization (International Society on Thrombosis and Hemostasis), the combined FV and FVIII deficiency is mainly associated with mild or moderate symptoms and patients rarely experience severe bleeding.
- Mild (> 40% activity): Patients are mostly asymptomatic, but might have problems with bleeding during trauma, a surgical procedure or with pregnancy/delivery
- Moderate (20-40% activity): Patients may have mild spontaneous bleeding, or bleeding triggered by trauma, surgery, or pregnancy/delivery
- Severe (< 20% activity): Patients may have spontaneous, severe, and even life-threatening bleeding
What causes it?
Combined factor V and VIII deficiency is a recessive disorder, meaning you need both your parents to pass on an affected gene in order to get the disease. The gene in question here is the one for the transporter that moves these factors outside the cell after they are made; the genes for both of the factors are normal. If you get only one copy of the affected transporter gene, you can be a carrier and pass the gene to your children. It occurs in men and women. Most cases are found around the Mediterranean Sea, especially in Israel, Iran, and Italy.
What are the symptoms?
Combined factor V and VIII deficiency is generally mild, and does not seem to cause more symptoms than either factor V or factor VIII deficiency. From more common to less common, symptoms include:
- Skin bleeding
- Heavy or prolonged menstrual bleeding (menorrhagia)
- Bleeding in the mouth, particularly after dental surgery or tooth extraction
- Bleeding after circumcision
- Abnormal bleeding during or after injury, surgery, or childbirth
- Nosebleeds (epistaxis)
- Bleeding into joints (hemarthrosis)
- Muscle bleeds
How is it diagnosed?
Combined factor V and factor VIII deficiency is diagnosed after finding prolonged screening tests (activated partial thromboplastin time, aPTT and prothrombin time, PT), then by following up to determine factor V and VIII activities are both lower than normal. These results should be confirmed by a specialized health care provider.
How is it treated?
Treatment for combined factor V and VIII deficiency can be through providing a source of multiple factors like fresh frozen plasma (FFP), administering factor VIII products, or administering desmopressin, which increases the amount of factor VIII in the bloodstream.
Excessive menstrual bleeding in women with combined factor V and factor VIII deficiency may be controlled with hormonal contraceptives (birth control pills), intra-uterine devices (IUDs), or antifibrinolytic drugs.