Essential Thrombocythemia - Causes, Symptoms, Diagnosis and Management

Introduction

Essential thrombocythemia is a rare genetic condition. The patient may develop clotting disorders in the blood. The situation is not cancer but a high risk of developing cancer. This is a slowly progressive disease.

What Is Essential Thrombocythemia and What Causes It?

In essential thrombocythemia, gene mutation occurs in the Janus kinase 2 gene, also known as JAK2. The cells proliferate as a result. The liver and kidney produce the hormone known as thrombopoietin, which binds to hematopoietic cell receptors. When it binds, those cells activate the JAK2 gene, which makes them divide and mature into megakaryocytes and platelets. Cells can also develop mutations in the thrombopoietin receptor, MPL, or the chaperone protein, calreticulin or CalR. During genetic mutations of the CalR, the signaling pathway remains active all the time. This makes the platelet increase even in the absence of thrombocythemia. Excess platelet production leads to the accumulation of blood clots in the deep vein of the legs, lungs, and abdomen. As a result, there is an increased chance of a heart attack, stroke, and miscarriage.

If Platelets are >1.5 million: This increases the risk of bleeding. This is due to the Von Willebrand factor. Platelets use up the free Von Willebrand factor, which leads to bleeding.

What Are the Symptoms of Essential Thrombocythemia?

Thromboses cause platelet plugs everywhere. Essential thrombocythemia develops symptoms like:

• Fatigue.

• Dizziness.

• Headache.

• Nausea.

• Tinnitus (ringing in the ears).

• Numbness in hands and feet.

• Visual disturbance.

• Deafness.

• Bleeding.

• Mega spleen or splenomegaly is caused due to overstress in the spleen.

Who Is Affected by Essential Thrombocythemia?

The affected population is:

• Thrombocythemia is a disease of the elderly.

• ET is more commonly observed in women than men.

• Pregnant women or childbearing women are more susceptible.

• People in their 50s are at high risk.

• Children are rarely affected by this condition unless genetically inherited or a chromosome-linked disorder.

• Effects two in 100,000 population in the United States.

• Mostly affects people between the ages of 60 to 80 years.

• About 20 percent of people affected are in the age group of 40 or below.

What Are the Clinical Manifestations Seen in Essential Thrombocythemia?

• Increased thrombocytes lead to bruising, bleeding, and erythromelalgia (an uncommon ailment that occasionally causes episodes of scorching sensation and redness in the hands, arms, legs, ears, and face, as well as the feet).

• Increased thrombosis leads to microthrombi, which causes headaches and visual disturbance.

• Symptoms of hyperviscosity syndrome are gout and hepatic splenomegaly which is rare.

What Are the Secondary Causes of Thrombocythemia?

Causes of secondary thrombocytosis are:

• Iron deficiency.

• Infection.

• Inflammation.

• Splenectomy (a surgical procedure to remove the spleen).

• Trauma.

• Surgery.

• Ischemia (reduced blood flow).

All of these symptoms are excluded before diagnosing essential thrombocythemia.

What Are the Complications Involved With Essential Thrombocythemia?

Essential thrombocythemia can lead to various life-threatening complications like:

• Heart Attack: The arteries which supply blood to the heart are clogged. This leads to heart attacks. Some symptoms include pressure in the chest lasting for minutes and radiating pain to the arms, jaw, shoulder, and back regions. Immediate essential life support is given.

• Stroke: Blood clots in arteries supplying the brain can lead to stroke or a transient ischaemic attack (TIA). Some of the manifestations associated with stroke are weakness or numbness in the facial area, arms, or legs, usually on one side of the body, difficulty in speaking or understanding speech, and blurred, double, or decreased vision. Immediate hospitalization is recommended after observing the signs and symptoms of a stroke.

• Pregnancy Complications: Essential thrombocythemia does not interfere with pregnancy. Hence most of the time, delivery is safe. But uncontrolled thrombocythemia can lead to abortions and other complications. Regular monitoring of the condition with proper medication timely is advised.

• Bone Marrow Problems: Bone marrow conditions can lead to leukemia. There are mainly two conditions associated with bone marrow failure. They are:

  • Acute Myelogenous Leukemia: This is a rapidly growing condition affecting the white blood cells and causing bone marrow cancer.
  • Myelofibrosis: Overproduction of white blood cells leads to deposition in the spleen. This leads to bone marrow scarring, severe anemia, and enlargement of the liver and spleen. Myelofibrosis is also a rapidly growing condition.

What Are the Symptoms Associated With Blood Clots?

As platelet level rises, blood clot formation takes place. Blood clots can form anywhere in the body but mainly occurs in the brain, hands, and legs. Here are some of the blood clot symptoms:

• Seizures.

• Migraines.

• Long-standing headaches.

• Numbness of hands and feet.

• Shortness.

• Chest pain.

• Increased heart rate.

• Epistaxis (bleeding from the nose).

• Hematuria (blood from urine).

• Bleeding gums.

• Blood in the stool.

• Bruises.

• Heavy menstruation.

How Is Essential Thrombocythemia Diagnosed?

All the normal physiological parameters are evaluated. Such as:

• Complete Blood Count (CBC): RBCs, TLC, and platelet levels are high. Especially platelet during a peripheral smear shows a high count and are large in size due to immature or megakaryocytes.

• Bone Marrow Biopsy: Generalized hypercellularity is seen because it is a myeloproliferative disorder. Both megakaryocyte hypertrophy and hyperplasia are seen.

• All secondary causes of thrombocythemia are excluded, including infections, inflammation, and iron deficiencies.

• Bleeding time is prolonged in essential thrombocythemia (ET).

• Genetic tests are conducted to study gene mutations.

• Increased blood viscosity is indicative of thrombosis.

How Is Thrombocythemia Treated?

Treatment for thrombocythemia depends on the risk of blood clots.

• In young and healthy patients who are at low risk of clots or bleeding, sometimes Aspirin is given, and platelet counts are monitored.

• When the risk of blood clots is high, therapy involves lowering the platelet count. This is done by using medications like Hydroxyurea, Interferon alpha, and Anagrelide.

• In individuals with extremely high platelet counts, plateletpheresis can be used. That is where platelets are collected and removed from the blood before the blood is returned to an individual. Plateletpheresis is a surgical procedure similar to dialysis.

Conclusion

Essential thrombocythemia is a myeloproliferative disorder with increased platelet or thrombocytes in the blood. Patients suffering from essential thrombocythemia should do periodic checks with a hematologist. In addition, the administration of aspirin therapy is beneficial against blood clotting dysfunction.