Platelet Count

Platelets are tiny cells in your blood that help it to clot.

What it is

Platelets, also known as thrombocytes, are small, irregular-shaped cell fragments that circulate in your bloodstream. They are produced in your bone marrow. Their primary role is to help stop bleeding by forming a plug at the site of an injury. When a blood vessel is damaged, platelets are activated, they stick to the injured area, and they clump together to form a temporary seal. They also release substances that help to form a more stable blood clot. A platelet count is a measure of how many platelets are present in a given volume of blood. In the UK, the typical reference range for a platelet count is between 150 and 450 billion platelets per litre of blood (150–450 x 10^9/l).

Why it matters

Your platelet count is an important part of your overall health picture.

A count that is too low (thrombocytopenia) can mean that your body may not be able to form clots effectively, potentially leading to increased or prolonged bleeding. This could manifest as bruising easily, nosebleeds that are difficult to stop, or bleeding gums. In more severe cases, it could lead to internal bleeding.

Conversely, a count that is too high (thrombocytosis) can increase the risk of blood clots forming within blood vessels. These clots can potentially block blood flow and lead to serious health issues like stroke or heart attack.

Therefore, monitoring your platelet count helps healthcare professionals assess your risk of bleeding or clotting and identify potential underlying health conditions.

What can cause it to be high or low

A variety of factors can influence your platelet count, leading to it being higher or lower than the typical range.

Factors that can lead to a low platelet count (thrombocytopenia) include:

• Bone marrow problems: Conditions affecting the bone marrow, where platelets are made, can reduce production. This can be due to certain cancers, aplastic anaemia, or exposure to radiation or chemotherapy.
• Immune system issues: Sometimes, the immune system can mistakenly attack and destroy platelets. This is seen in conditions like immune thrombocytopenia (ITP).
• Infections: Certain viral infections, such as HIV, hepatitis C, or even the common cold, can temporarily lower platelet counts.
• Medications: Some medicines can affect platelet production or increase their destruction.
• Enlarged spleen: The spleen filters blood and can sometimes trap too many platelets, leading to a lower count in circulation.
• Pregnancy: Mildly low platelet counts can sometimes occur during pregnancy.

Factors that can lead to a high platelet count (thrombocytosis) include:

• Inflammation: Chronic inflammatory conditions, such as rheumatoid arthritis or inflammatory bowel disease, can sometimes lead to an increased platelet count.
• Infection: Acute infections can sometimes trigger a temporary rise in platelets.
• Iron deficiency anaemia: This is a common cause of a high platelet count.
• Following surgery or injury: The body may temporarily increase platelet production after surgery or significant injury as part of the healing process.
• Certain blood disorders: In rarer cases, a high platelet count can be a sign of a myeloproliferative neoplasm, a group of disorders where the bone marrow produces too many of one or more types of blood cells.

Lifestyle factors that may help

While many causes of abnormal platelet counts require medical intervention, certain lifestyle choices can support overall blood health and may be beneficial to discuss with your GP.

• Balanced Diet: Ensuring you have a diet rich in essential vitamins and minerals can support healthy bone marrow function. Foods rich in iron, vitamin B12, and folate are particularly important for blood cell production.
• Hydration: Staying adequately hydrated is crucial for maintaining healthy blood volume and circulation.
• Avoiding Smoking: Smoking can negatively impact blood vessel health and circulation, which may indirectly affect platelet function and overall blood health.
• Moderate Exercise: Regular, moderate physical activity can improve circulation and overall cardiovascular health. It’s important to find an activity level that is appropriate for your individual health status.

Questions to discuss with your GP

If your platelet count has been flagged as outside the normal range, or if you have concerns about bleeding or clotting, it’s a good idea to have a conversation with your GP. Here are some questions you might consider asking:

• What does my specific platelet count mean for my health?
• Are there any underlying conditions that might be causing my platelet count to be high or low?
• What further tests, if any, might be needed to investigate my platelet count?
• Are there any lifestyle changes that could support my platelet levels?
• What signs or symptoms should I watch out for that might indicate a problem related to my platelet count?
• How often should my platelet count be monitored?