Definition
One speaks of thrombocytosis when the number of thrombocytes, i.e. blood platelets, in the blood is increased. In thrombocytosis, more than 500,000 platelets per microliter are found in the blood. Platelets are responsible for blood clotting.
They ensure that the wound closes again after an injury by forming a blood clot. If there are too many platelets, as is the case with thrombocytosis, blood can clump together and lead to complications. There are two different types of thrombocytosis. Reactive (secondary) thrombocytosis refers to a reaction to an underlying disease, whereas essential (primary) thrombocytosis is an independent disease.
Causes of thrombocytosis
Thrombocytosis can either be a consequence of another underlying disease (secondary thrombocytosis) or an independent disease (primary thrombocytosis). In primary thrombocytosis, also known as thrombocytopaemia, there is a functional disorder in the haematopoietic system. This disease is genetically inherited and affects the bone marrow in which the blood is produced.
It belongs to the malignant diseases. More often, however, secondary thrombocytosis is present, which can have various causes. Chronic inflammatory diseases can lead to thrombocytosis.
These include, for example, rheumatic diseases or Crohn’s disease. Acute infections or inflammations can also lead to an increase in the value. Also a large loss of blood, as it occurs with injuries or operations, can cause an increase in blood platelets.
Stomach ulcers associated with heavy bleeding can also be the trigger. After surgical removal of the spleen (splenectomy), the patient usually has thrombocytosis, since the spleen is responsible for the breakdown of blood platelets. Furthermore, thrombocytosis is typical of chronic iron deficiency and can also be triggered by pregnancy, taking the contraceptive pill or smoking.
In addition, competitive athletes can also develop thrombocytosis as a result of high physical activity. Other possible causes are cancer and chemotherapy. Thrombocytosis can also occur in healthy people.
This can be caused by stress, fear or depression. Chronic iron deficiency is a possible cause of thrombocytosis. Iron is needed by the body to form new red blood cells.
Chronic iron deficiency therefore leads to anaemia. In response, the production of blood platelets is stimulated. However, the exact mechanism is not yet known.
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