Factor X Deficiency - Causes, Symptoms, Diagnosis, and Treatment

What Is Factor X (Stuart Prower Factor)?

Factor X (Stuart Prower Factor) is a clotting factor protein present in the bloodstream produced by the liver. Factor X deficiency was first seen in the 1950s in the US (United States) and England in two patients — Rufus Stuart and Andrey Prower; therefore, the name is suggested after them.

The human body has different types of clotting factors synthesized by the liver and flowing into the bloodstream, and these clotting factors help form the plug at the site of the injury that stops the bleeding by forming a clot. Factor X is also required in this coagulation process. It plays an essential role in activating enzymes in the coagulation cascade. In the process of hemostasis, factor X activates the enzyme in the common pathway in the presence of vitamin K.

What Is Factor X Deficiency?

Factor X deficiency is a rare autosomal recessive blood disorder. It leads to prolonged clotting bleeding time. It is a genetically transmitted disease caused by a mutation of the F10 gene. It can be asymptomatic with symptoms or severe deficiency.

Some underlying disorders can also cause factor X deficiency. It affects both males and females and is seen in one in 500000 to a million people.

What Is the Role of Factor X in the Coagulation Process?

The coagulation process comes under the secondary stage of hemostasis. Blood clotting or coagulation occurs in three stages-

1. Formation of prothrombin activator.

2. Conversion of prothrombin into thrombin.

3. Conversion of fibrinogen into fibrin.

All these stages occur through three pathways.

Intrinsic Pathway- The intrinsic pathway follows the following steps:

1. The endothelium, smooth muscle, and collagen get damaged and exposed at the injury site.

2. The exposed collagen activates factor XII (Hageman factor) in the presence of a high molecular weight kininogen.

3. Activated factor XII converts factor XI (plasma thromboplastin antecedent factor) into active factor XI.

4. The activated factor XI activates factor IX (Christmas factor) in the presence of factor V (calcium).

5. The activated factor IX activates factor X in the presence of factor VIII (antihemophilic factor) and calcium.

6. The exposed collagen comes in contact with platelets and releases phospholipids.

7. The activated factor X, phospholipids, and factor V react to form a prothrombin activator.

Extrinsic Pathway - The extrinsic pathway follows the following steps.

1. At the site of injury, the damaged tissues release factor III.

2. Factor III (thromboplastin) contains proteins, phospholipids, and glycoproteins.

3. Glycoprotein and phospholipids components of thromboplastin convert factor X into active factor X in the presence of factor VII (stable factor).

4. The activated factor X with factor V and phospholipids reacts to form a prothrombin activator.

Common Pathway -

1. Intrinsic and extrinsic pathways form the prothrombin activator and convert prothrombin into thrombin in the presence of factor V.

2. The effect of thrombin is called positive feedback.

3. The thrombin converts inactive fibrinogen into activated fibrinogen; the activated fibrinogen is called – a fibrin monomer.

4. The fibrin monomer polymerizes with other monomers and forms loosely arranged fibrin strands.

5. These loose strands of fibrin are modified into dense and tight fibrin threads by factor XIII (fibrin-stabilizing factor) in the presence of calcium ions.

6. The tight fibrin threads get aggregated all together to form a meshwork of stable clots.

What Are the Symptoms of the Deficiency of Factor X?

The symptoms of factor X deficiency can vary between individuals with asymptomatic and symptomatic defects. In severe cases, both external and internal bleeding is seen.

Symptoms of the deficiency of factor X are as follows -

1. Bruising- Easily bruising is seen. Dark blue-black hematomas are present.

2. Epistaxis- Epistaxis (nosebleed) is very commonly seen.

3. Gingival Bleeding- Gingival bleeding or gum bleeding is seen at the time of brushing.

4. Excessive Bleeding- Excessive bleeding after surgery or trauma.

5. Prolonged Bleeding- Prolonged bleeding after dental treatment like extraction.

6. Joint Bleeding- Hemarthrosis is present in the deficiency; the joint cavity has articular bleeding.

7. Muscle Bleeding- Muscular hematoma leads to muscle bleeding because of the deficiency.

8. Gastrointestinal Bleeding- Factor X deficiency can induce other underlying disorders like iron deficiency which causes gastrointestinal bleeding.

9. Intracranial Bleeding- Bleeding in the brain and spinal cord is also seen in severe deficiency of factor X.

10. Bleeding Problem in Newborns- Newborns with factor X deficiency show abnormal umbilical stump bleeding. In newborn males, they show prolonged bleeding during circumcision.

11. Menstrual Bleeding- In women, heavy menstrual bleeding is seen. Chances of miscarriage are present with the deficiency.

12. Antepartum Hemorrhage- Bleeding in the second half of pregnancy and before the child's birth.

What Are the Causes of the Deficiency of Factor X?

The deficiency of factor X can be an inherited or an acquired disorder.

An Inherited Deficiency of Factor X -

In the disorder's genetic transmission, there is an alteration of the F10 gene. This is responsible for the production and the working of factor X. The mutation of the gene leads to defective production of the factor and insufficient or overproduction of the factor. It is an autosomal recessive inheritance disorder; an individual can be a carrier of the disease and remains asymptomatic. The chances of transmitting the disease to the child when both parents are carriers of the disease are 50 percent, whereas if a single parent is the carrier disease, the chances are about 25 percent.

In an Acquired Deficiency of Factor X -

The acquired deficiency of factor X is more common than the inherited deficiency of factor X. In addition, the individual may suffer from other underlying disorders such as — liver disorders, hemophilia, iron deficiency, and aplastic anemia. Deficiencies of the other clotting factors can also induce prolonged clotting time.

What Are the Investigations for the Diagnosis of the Factor X Deficiency?

The deficiency of factor X can be diagnosed by performing some investigations.

Recording Medical History -

Past family and personal history help to diagnose the disease.

Routine Blood Tests -

1. Clotting time.

2. Bleeding time.

3. Prothrombin time.

4. Thrombin time.

5. Partial prothrombin time.

What Is the Treatment of Factor X Deficiency?

The following medications can treat the deficiency of Factor X -

1. Human coagulation factor X – Coagadex is a concentration of factor X injected into the body. It is used in adults and children with mild to moderate symptoms.

2. Prothrombin complex concentrates (PCCs) are the concentrates containing factors II, VII, IX, and X.

3. Fresh frozen plasma is injected into the patient's body, containing all the clotting factors.

4. Antifibrinolytic and birth control pills can also be administered to treat factor X deficiency.

Conclusion-

Factor X deficiency is an autosomal rare disorder; it cannot be prevented, but safety measures can be taken before any treatment; informing the doctor about the condition can help the doctor plan treatment accordingly and avoid a probable mishap during the treatment. Advancements in medical science also bring optimistic hope for treating the deficiency of factor X.