Thrombocytosis: Types, Symptoms, Causes, Effects, Diagnosis and Treatment

It is a condition in which there is an excessive number of platelets in the blood. Platelets are blood cells that stop bleeding by joining together to form a clot.

Too many platelets can lead to certain conditions, which include stroke , heart attack or a blood clot.


There are two types of thrombocytosis:

Primary: also known as Essential Thrombocythemia (ET), is a disease in which abnormal cells in the bone marrow cause an increase in platelets.

The cause is unknown. It is not considered a hereditary condition despite the finding of certain genetic mutations in the blood or bone marrow.

Secondary: is caused by another condition that the patient may be suffering from, such as:

  • Iron deficiency anemia.
  • Cancer.
  • Inflammation or infection
  • Surgery, especially splenectomy (removal of the spleen).


Thrombocytosis rarely causes symptoms. If symptoms occur, these may be:

  • Headache.
  • Dizziness or lightheadedness
  • Chest pain.
  • Weakness.
  • Fainting.
  • Numbness or tingling of the hands and feet.

When to see a doctor?

Because this condition usually causes no symptoms, the affected person will not know they have the disease unless a routine blood test reveals a higher than normal amount of platelets.

If the results of your blood tests show a high platelet count, your doctor will try to determine the reason.

Causes of Thrombocytosis

Throughout the world, iron deficiency is the most common cause of thrombocytosis.

The symptoms of anemia are reduced energy, lethargy, dyspnea on exertion, heart palpitations and, when extreme, coronary insufficiency or other ischemia of the final organ.

The bone marrow, spongy tissue inside the bones, contains stem cells that can become red blood cells, white blood cells or platelets.

Platelets come together, which helps the blood form a clot that stops bleeding when a blood vessel is damaged.

A normal platelet count varies from 150,000 to 450,000 platelets per micro liter of blood.

If you have Thrombocytosis from a bone marrow disorder, the bone marrow overproduces the cells that make up the platelets and releases too many platelets into the blood.

Therefore, if the results of your blood tests reveal a high platelet count, it is important that your doctor determine if you have primary or secondary thrombocytosis.

The causes include:

  • Acute bleeding and blood loss.
  • Allergic reactions.
  • Cancer.
  • Chronic renal failure or other kidney disorder.
  • Exercise.
  • Heart attack.
  • Derivation of the coronary artery.
  • Infections, including tuberculosis.
  • Lack of iron.
  • Vitamin deficiency.
  • Pancreatitis.
  • Trauma.
  • Burns.


Thrombocytosis can cause severe bleeding or complications of coagulation. In general, it can be avoided by maintaining good control of the platelet count with medication.

The transformation of the disease to leukemia occurs in a small percentage of patients.

What is the differential diagnosis for this problem?

The differential includes reactive (secondary) or essential (primary) thrombocytosis.

Secondary or reactive thrombocytosis accounts for 80-90% of cases.

Causes of secondary thrombocytosis include infection, inflammatory conditions (eg, inflammatory bowel disease), physical stress (including postoperative status), acute blood loss, iron deficiency anemia, post-splenectomy, and underlying malignancy.

Primary or autonomic thrombocytosis is a process of clonal bone marrow. The disorders include Thrombocythemia (ET) essential, polycythemia vera, primary myelofibrosis and chronic myeloid leukemia.

Familial thrombocytosis is a genetically heterogeneous disorder and a rare entity.

Treatment of Thrombocytosis

In most people with this condition, treatment can wait. It is very unusual for the treatment to be emergent.

In the chronic context, treatment is generally only indicated for thrombocytosis due to a myeloproliferative neoplasm.

This is probably due to one of many functional abnormalities present in the blood cells of patients with ET or PV, in contrast to functionally normal platelets and other blood cells produced in patients with reactive thrombocytosis.

What imaging studies are useful to detect the condition?

Occasionally, abdominal ultrasound may reveal moderate splenomegaly or portal vein or liver thrombosis, which is not obvious on physical examination, and which indicates chronic inflammation (which is usually obvious) or a primary myeloproliferative neoplasia.

What therapies are useful to reduce complications?

Interventions aimed at restoring blood flow are essential and their effectiveness is limited over time.

Thrombolytic therapy, percutaneous coronary intervention, cerebral vascular interventions and Bypass surgery are all appropriate for certain environments.

Once out of the acute context, antiplatelet agents are generally indicated to reduce thrombotic complications.