Is Factor II Deficiency?
Factor II deficiency is a very rare blood clotting disorder. It
results in excessive or prolonged bleeding after an injury or surgery. Factor
II, also known as prothrombin, is a protein made in your liver. It plays an
essential role in blood clot formation. It is one of about 13 clotting factors
involved in the proper formation of blood clots.
Are the Symptoms of Factor II Deficiency?
Symptoms may vary from mild to severe. In very mild cases, blood
clotting may just be slower than normal.
In cases of severe factor II deficiency, symptoms may include:
- umbilical cord bleeding at birth
- unexplained bruising
- abnormal bleeding after giving birth, having
surgery, or being injured
- prolonged nose bleeds
- bleeding from the gums
- heavy or prolonged menstrual periods
- internal bleeding in your organs, muscles,
skull, or brain (relatively rare)
Role Does Factor II Play in Normal Blood Clotting?
To understand factor II deficiency, it helps to understand the
role of factor II (prothrombin) and its activated version, factor IIa
(thrombin), in normal blood clotting. Normal blood clotting occurs in four
stages, described below.
When you have a wound or surgery, your blood vessels are broken. The
broken blood vessels immediately constrict to slow blood loss. The damaged
vessels then release special cells into your bloodstream. They signal the blood
platelets and clotting factors circulating in your bloodstream to come to the
Formation of a Platelet Plug
Blood platelets (specialized blood cells responsible for
clotting) are the first responders to the site of a damaged blood vessel. They
attach themselves to the injured blood vessel and to each other, creating a
temporary patch over the injury. This first stage of blood clotting is known as
Formation of a Fibrin Plug
Once the platelets form a temporary plug, blood-clotting factor
II (prothrombin) changes to its activated version, factor IIa (thrombin).
Factor IIa causes factor I (fibrinogen) to make the stringy protein fibrin.
Fibrin wraps itself in and around the temporary clot until it becomes a hard
fibrin clot. This new clot seals the broken blood vessel and creates a
protective covering over the wound. This is called secondary hemostasis.
Wound Healing and Dissolution of the Fibrin Plug
After a few days, the fibrin clot starts to shrink,
pulling the edges of the wound together to promote new tissue growth. As the
new tissue closes the wound, the fibrin clot dissolves.
If you don’t have enough factor II, your body will not be able to
form secondary fibrin clots properly. As a result, you may have prolonged and
Causes Factor II Deficiency?
Factor II deficiency may be inherited. It can also be acquired as
a result of disease, medications, or an autoimmune response.
Hereditary factor II
deficiency is extremely rare. It is caused by a recessive gene,
which means that both parents must carry the gene in order to pass the disease on.
There are currently only 26 documented cases of inherited factor II deficiency
in the world.
Acquired factor II
deficiency is usually caused by an underlying condition, such
- vitamin K deficiency
- liver disease
- medications such as anticoagulants (e.g., warfarin
- production of autoimmune inhibitors that disable
healthy clotting factors
Is Factor II Deficiency Diagnosed?
Diagnosis of factor II deficiency is based on your medical
history, any family history of bleeding problems, and lab tests. Lab tests for
bleeding disorders include:
- factor assays:
these tests check the performance of specific factors to identify
missing or poorly performing factors
II assays: to measure levels of factor II in your blood
time (PT): to measure
levels of factors I, II, V, VII, and X based on how fast your blood clots
- prtial prothrombin
time (PTT): to measure levels of factors VIII, IX, XI, XII, and von
Willebrand factors based on how fast your blood clots
tests for underlying conditions that may be causing your bleeding
Is Factor II Deficiency Treated?
Treatment of factor II deficiency focuses on controlling bleeds,
treating underlying conditions, and taking preventive steps before surgeries or
invasive dental procedures.
Treatment for bleeding episodes may include infusions of
prothrombin complex, a mixture of factor II (prothrombin) and other clotting factors,
to boost your clotting ability. Infusions of fresh frozen plasma (FFP) have
been used in the past. They are less common today, thanks to lower-risk
Treatment of Underlying Conditions
Once your bleeding is under control, underlying conditions that
impair blood platelet function can be treated. If your underlying condition
cannot be resolved, the focus of your treatment will shift to managing the
symptoms and impacts of your clotting disorder.
Prophylactic Treatment Before Surgery
If you are planning any surgeries or invasive procedures,
infusions of clotting factor or other treatments may be required to minimize
Is the Long-Term Outlook for Factor II Deficiency?
With proper control, you can lead a normal and healthy life with
mild to moderate factor II deficiency. If your deficiency is severe, you will
need to work closely with a hematologist (a doctor who specializes in blood
disorders) throughout your life to reduce bleeding risks and control bleeding