What Does a High Platelet Count Mean

To understand what does a high platelet count mean, you must first understand what platelets are. Blood platelets are specialized blood cells that facilitate the coagulation of blood. If these are present in abnormally high numbers, it could have an adverse impact on the overall health of the affected individual. Let's learn about the contributory factors for an abnormally high platelet count.
HealthHearty Staff
Last Updated: Apr 22, 2018
Blood is a specialized body fluid that performs various important functions. The components of blood include blood platelets, white blood cells, red blood cells, and blood plasma. Platelets, which are also medically referred to as thrombocytes, are small disk-shaped specialized blood cells. These are cell fragments which originate from the cytoplasm of a giant bone marrow cell called megakaryocyte. Megakaryocytes originate from the pluripotential stem cells present in the bone marrow. Thrombocytes don't have a definite nucleus. These don't contain hemoglobin and DNA. However, these specialized cells contain certain chemicals that help the blood coagulate. So, it's the thrombocytes that help in preventing blood loss in event of injuries.
Under normal circumstances, the platelet count should lie between 1,50,000 - 4,50,000 thrombocytes per microliter of blood. In case, a deviation from this normal range is observed, further investigation would be required to find out the underlying cause of this condition. When the underlying cause of a high platelet count isn't known, it is medically referred to as thrombocythemia. When another medical condition gives rise to a high platelet count, it is called secondary or reactive thrombocytosis. A person is diagnosed with thrombocytopenia when the thrombocyte count is lower than the normal range.
How Blood Platelets Work
Thrombocytes facilitate the process of hemostasis, that is clotting of blood. These get activated whenever an injury causes a blood vessel to rupture. The damaged thrombocytes release an enzyme called thrombokinase. This enzyme converts prothrombin present in blood into thrombin. A reaction between thrombin and soluble fibrinogen results in the formation of insoluble fibrin. This is followed by the formation of thread-like structures, which form a sticky mass at the site of injury. This causes the blood to clot. Thrombocytes have a short life span of about eight to ten days, but the bone marrow continues to produce new blood platelets. These new platelets are then circulated throughout the body. This helps in keeping the numbers of thrombocytes within the normal range, however, certain medical conditions can cause fluctuations in the platelet count.
What Causes a High Blood Platelet Count
Essential thrombocythemia occurs when the faulty stem cells in the bone marrow start producing too many thrombocytes. Chronic myelogenous leukemia, essential thrombocythemia, polycythemia vera and primary myelofibrosis are classified under a class of disorders called myeloproliferative disorders. Polycythemia vera is a condition that is characterized by increased production of platelets. This condition is also marked by an increased production of red blood cells and white blood cells. Chronic myelogenous leukemia is a cancer that starts within the bone marrow. Primary myelofibrosis is characterized by fibrosis or development of excess fibrous tissue in the bone marrow. Genetic predisposition might have a role to play in the development of these conditions. Certain studies have revealed that people who have been exposed to radiation could be at a risk of developing myeloproliferative disorders.
An increased production of platelets can also be caused by other disorders. Secondary or reactive thrombocytosis may occur as a result of infection, surgery or prolonged use of certain drugs. Infectious or inflammatory diseases, iron deficiency anemia, abnormal spleen function, splenectomy (removal of spleen), kidney disorders, pancreatitis, heart attack, or acute bleeding could also be responsible for raising the platelet count. Overdosing on medication for thrombocytopenia could also increase the platelet count.
Symptoms and Treatment of a High Platelet Count
Since thrombocytes facilitate the coagulation of blood, an increase in their numbers results in the formation of blood clots. Formation of blood clots in blood vessels could limit the flow of blood to various parts of the body which in turn could lead to serious health problems. The common symptoms of thrombocytosis include easy bruising, tingling sensation, headaches, weakness, and dizziness. In severe cases, thrombocytosis could increase the risk of serious problems such as heart attack, stroke or enlargement of spleen. If the increase in the numbers of thrombocytes is attributed to diseases other than a bone marrow disorder, treating the underlying medical condition will help in lowering the blood platelet count.
The diagnosis of the underlying cause is central to the treatment of thrombocytosis. Routine blood tests or blood smear test are usually conducted for examining the platelet count as well as the structure of thrombocytes. If the need arises, doctors might think about performing genetic testing or bone marrow aspiration and biopsy. The treatment is aimed at resolving the underlying condition with the help of drugs. If the blood samples indicate an increase in the viscosity of blood, doctors might prescribe blood-thinning medicines. If the bone marrow seems to be producing a large number of thrombocytes, drugs that slow down the production of thrombocytes by bone marrow are usually prescribed.
Since serious medical conditions could be responsible for causing a high blood platelet count, people experiencing the aforementioned symptoms must get themselves medically examined soon. A timely diagnosis and treatment will certainly help in alleviating the symptoms and normalizing the thrombocyte count. An early diagnosis will improve the chances of a speedy recovery, so do consult a doctor if you experience any of the aforementioned symptoms.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.