Introduction
Stuart-Prower deficiency is the deficiency of factor X, a blood clotting factor. The deficiency of this factor may result in a condition in which the blood may not clot even after small injuries like a minor cut. It was originally detected in England and The United States in 1950 by two physicians, namely Rufus Stuart and Audrey Prower (by which this disease got its name Stuart-Prower deficiency). This disease is seen in one in fifty thousand to one million and occurs as a rare genetically acquired disease in which both males and females are equally affected. The clotting factor X (the tenth clotting factor) is a vitamin K-dependent factor synthesized in the parenchymal cells of the liver. It shows a concentration of 1 ml/dl (milliliter per deciliter). Although the condition cannot be reversed, with the benefits of advanced medicine, it is well managed and tolerated, allowing patients and doctors to give and provide treatment.
What Are the Types of Factor X Diseases?
Factor X deficiency is one of the rarest deficiencies and is seen as two different types. They are:
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Inherited Factor X Deficiency: The inherited deficiency is usually transmitted from the parent gene. It is seen involving both male and female patients. The reason is unknown, and the patient will mostly be asymptomatic or show mild bleeding tendencies.
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Acquired Factor X Deficiency: As the name indicates, this occurs due to systemic conditions like liver diseases, vitamin K deficiency, or anticoagulant drugs like Warfarin. Factor X deficiency is also seen in conditions like amyloidosis (a clinical condition characterized by protein buildup in organs) and chronic lymphoid leukemia.
How Does Stuart-Prower Deficiency Occur?
Blood clotting occurs as a series of events, also called the clotting cascade, in which factor X is derived from factor Xa, an active serine protease enzyme. The first step of the common clotting pathway is the formation of a thrombus (blood clot). Here factor X can be activated by both extrinsic (external factor) or intrinsic factors (internal factor), where the extrinsic pathway is activated by factor VII and the intrinsic pathway by factor IX and factor VIIIa, both of which need calcium and phospholipid ions on the surface. The cause for congenital factor X deficiency occurs due to mutations in the GLA-domain factor X, a residue of 39 peptides in the light chain of the clotting factors. And the acquired factor X- deficiency is associated with vitamin K deficiency.
How Commonly Is Stuart-Prower Deficiency Seen?
Inherited factor X deficiency is considered one of the rarest disorders of clotting factors seen among one in fifty to one million people. Equally, it affects both men and women of all age groups, usually seen in kids when identified as a congenital disability and in adults in case of acquired diseases. This is a lifetime disorder where people are more prone to bleeding.
What Are the Clinical Symptoms of Stuart-Prower Deficiency?
The clinical symptoms seen in patients vary from person to person, depending on severity. Patients are more prone to bruising, bleeding in the nose and mouth in case of mild factor X deficiency. The symptoms of patients with severe factor X deficiency are joint bleeding, excessive umbilical cord bleeding, intramuscular bleeding, and a very high risk for intracranial bleeding during the first few weeks of birth. Women with factor X deficiency also show symptoms like menorrhagia (abnormal vaginal bleeding) or intense menstrual bleeding. Pregnant women may also experience miscarriages during the first trimester or excessive blood loss soon after labor which may even be fatal. Hence it is very important to get an opinion from a hematologist (blood specialist ) and obstetrician (the doctor who handles deliveries) before childbirth.
How Is Stuart-Prower Deficiency Evaluated?
Most of the time, the cases of Stuart Prower deficiency are almost unnoticed or silent. Hence, it requires proper diagnostic tests to evaluate and differentiate the exact form of hemophilia. The tests used to confirm Stuart-Prower deficiency are done by blood evaluation. The tests performed are:
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Prothrombin Time Test (PT): Prothrombin is a type of clotting factor present in the bloodstream, which is responsible for the clotting nature of the blood.The prothrombin test is used to evaluate blood clotting time. These are laboratory tests in which the blood is taken and tested for clotting time.
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Partial Thromboplastin Time (PTT): The partial thromboplastin time is used to measure the bleeding time or the entire time taken for the blood to clot.
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Activated Partial Thromboplastin Time (APTT): This screening test is used to measure blood clotting time.
All these tests are used to check if the bleeding and the clotting time are normal. The average normal bleeding time is between two to nine minutes, and the average normal clotting time is ten to thirteen seconds.
How Is Stuart-Prower Deficiency Treated?
In mild to moderate inherited factor X deficiency, the FDA (Food and Drug Administration) approved a coagulating product called Coagadex, derived from human plasma, to treat bleeding episodes and their frequency in children and adults. However, before the development of this drug in 2015, the agents commonly used were fresh frozen plasma or plasma-derived platelet complex concentrate (PCC). However, during this procedure, the need for the PCC was in higher volumes and must be treated with caution. The other medications used are Aminocaproic acid or Tranexamic acid, and topical drugs like fibrin glue, styptic, or nose bleed powders were given to treat milder symptoms. Restoring the circulatory blood levels of factor X shows a 10 to 40 percent normalcy. The underlying diseases are generally treated in patients with acquired factor X deficiency.
Conclusion
Stuart-Prower deficiency or hemophilia X is an extremely rare condition of the clotting factor X which is genetically inherited and is seen affecting both men and women equally. Although there is no cure for this disease, it is likely to be managed through medical management approaches and by following preventive methods in cases of acquired conditions like liver disease. It is an extremely rare condition, seen only in one-third of the population, and likely to be treated in a very conventional manner. The treatment approach of hemophilia in milder patients shows a good to excellent prognosis, simultaneously increasing the lifespan of people.
