Overview

Thrombocytopenia (thrombo-cyto-penia) is a type of bleeding disorder. Thrombocytopenia is a condition due to a deficiency of platelets in the blood. Platelets (also known as thrombocytes) are blood cells that are normally made in the bone marrow and have key roles in wound healing and blood clotting to prevent excessive bleeding. Platelet deficiency can be a result of various causes, including bone marrow disorder or side effects of certain treatments.¹

Signs and symptoms

Depending on the underlying cause and severity, the signs or symptoms in people with thrombocytopenia can range from mild to life-threatening. Often individuals with thrombocytopenia do not notice symptoms until they have an injury or during medical procedure(s). These can appear suddenly or over time. Thrombocytopenia can show characteristic signs often because of bleeding.^1,2

• Purpura - easy and/or excessive bruising after minor injuries.
• Petechiae - small and flat red-purple pinpoint spots. 
• Increased or prolonged bleeding after minor injuries e.g., cuts.
• Unusually heavy menstruation.
• Nosebleeds - frequent or prolonged, especially in children. 
• Gum bleeding - frequent or prolonged, e.g., while brushing or flossing. 
• Tiredness - chronic bleeding can lead to anaemia, contributing to tiredness and weakness.
• Severe headaches.
• Enlarged spleen. 

Internal bleeding may occur in rare or severe cases, such as:^4,8,9

• Blood in vomit, urine, or stool. 
• Eyes - retinal or subconjunctival. 
• Stomach and intestine.
• Within the brain (intracranial).
• Heart attack. 
• Pregnancy complications. 

 If you suspect that you or anyone is having symptoms of serious bleeding, stroke, or heart attack, seek emergency support immediately. 

Understanding platelets 

To understand the effect of thrombocytopenia, we first need to understand why normal levels of platelets are important for us.  

Role of platelets in blood clotting

These blood cells have the unique ability to help blood clot (also known as thrombus). If you are bleeding or injured, many platelets stick together to form a plug to seal the wound. Therefore, in thrombocytopenia, there is a reduced ability to form blood clots. This means that you may have trouble stopping the bleeding. The severity of bleeding can vary depending from where the bleeding is occurring and how low your platelet count is.¹ 

Normal platelet count 

So, what is our platelet count meant to be? Generally, the acceptable normal platelet count ranges between 150,000 to 450,000 platelets per microlitre of blood, in healthy children and adults. Thrombocytopenia is when the platelet count is less than 150,000 per microlitre of blood. The lower the platelet count, there is more increased risk of bleeding symptoms.^1,3,7,10 

• Mild thrombocytopenia: platelet levels between 100,000 and 150,000 per microliter of blood.
• Moderate thrombocytopenia: platelet levels between 50,000 and 100,000 per microlitre of blood.
• Severe thrombocytopenia: platelet levels less than 50,000 per microlitre of blood. 

But it is also important to note that some individuals can have high or low platelet counts as their own normal. Furthermore, the laboratory reference ranges can vary, including for pregnant women who usually show a decrease in platelet numbers as the pregnancy progresses.¹⁰  

Causes of thrombocytopenia

Thrombocytopenia can be a result of various underlying causes which are not limited to those listed below. These can be divided into 3 main groups.^4,5 

Decreased platelet production 

• Bone marrow disorder e.g., aplastic anaemia, myelofibrosis, leukaemia, myelodysplasia.
• Viral infections e.g., human immunodeficiency virus (HIV), hepatitis C and Epstein-Barr Virus .
• Drugs e.g., chemotherapy, anticoagulants, medications. 
• Heavy alcohol consumptions. 
• Genetic - hereditary thrombocytopenia. 
• Cancer. 
• Nutritional deficiencies e.g., Vitamin B12 and/or folate.

Increased platelet destruction 

Immune causes:

• Immune thrombocytopenic purpura (ITP).
• Heparin-induced thrombocytopenia (HIT)
• Drug-induced antibodies e.g., heparin, quinine, sulfa-containing antibiotics and anticonvulsants. 
• Bacterial infection in the blood (bacteraemia).  
• Post-transfusion purpura.
• Connective tissue diseases.
• Autoimmune disorders e.g., thyroid disorders, systemic lupus erythematosus, rheumatoid arthritis. 

Non-immune causes:

• Pregnancy - usually mild and improves after childbirth. 
• Disseminated intravascular coagulopathy (DIC).
• Thrombotic
• Thrombocytopenic purpura (TTP) - rare conditions involving sudden formation of small blood clots throughout the body.
• Haemolytic uraemic syndrome (HUS) - rapid decline in platelets, destruction of red blood cells and causes kidney damage.

Splenic sequestration 

Normally, platelets can pass through the spleen without being accumulated or trapped. However, in splenic sequestration, the enlarged spleen leads to an increased number of platelets being trapped. This reduces the number of platelets circulating in the bloodstream. This can occur very suddenly. 

Diagnosis of thrombocytopenia

Early diagnosis is important for earlier treatment and addressing other potential complications of thrombocytopenia. 

Clinical evaluation

Your healthcare provider will consider your signs and symptoms, including any relevant medical conditions you and your family may have. They can also perform a thorough physical examination, including looking for any signs of bleeding, bruises, anaemia, infection etc.^1,6 

Complete blood count 

A trained healthcare professional will perform your blood test to thoroughly investigate. Complete blood count test can be used to measure various levels of platelets, blood cells, inflammatory markers and other vitamins and minerals such as C-reactive protein (CRP), Erythrocyte sedimentation rate (ESR), liver function, vitamin B12, folate and iron.⁶  

Blood clot test

This is another type of blood test which generally focuses on the time it takes for your blood to clot, by checking the partial thromboplastin time (PTT) and prothrombin time (PT). 

Blood smear test 

Also known as peripheral blood smear or blood film. This is a diagnostic procedure which involves collecting and examining a small drop of your blood under a microscope. This test allows us to visually check the blood cells including the amount, size, shape, and overall appearance. Thus, blood smear tests can help to identify if there are any underlying causes of thrombocytopenia.⁷  

Depending on the clinical evaluation, clinicians may request more investigations to further confirm the diagnosis, for example.⁶ 

• Bone marrow biopsy.
• X-ray imaging. 
• Pelvic ultrasound. 
• Faecal immunohistochemical test (FIT). 
• Colonoscopy.   

Treatment options

Treatmentforthrombocytopeniadependsontheunderlyingcause,severity, and symptoms. In some cases, thrombocytopenia can resolve itself, while others require ongoing treatment and management. If you are not suffering from any symptoms, the management would just be to monitor. Alternatively, if you require urgent treatment, your healthcare advisor will urgently refer you to the haematology specialist or to the oncologist for more tailored treatment .^2,4,6 Your healthcare advisor can help identify ways to improve your platelet counts by treating the underlying cause.¹  

Treating the underlying cause

If your thrombocytopenia is due to medication or underlying cause. This can include readjusting or discontinuing the causative medication would be the first recommended step.¹ 

Medications  

• Platelet-stimulating medications - e.g., eltrombopag and romiplostim, can help increase the production of platelets in the bone marrow 
• Corticosteroids - e.g., prednisone, may be considered to suppress the immune system if the underlying cause of thrombocytopenia is due to an autoimmune reaction 
• Immunoglobulin - e.g., rituximab, may be considered to increase platelet levels in certain autoimmune cases 

Blood or platelet transfusion

In severe thrombocytopenia, platelet transfusion may also be an option to temporarily replenish your platelet counts. This involves receiving a platelet transfusion through an intravenous (IV) line inserted into a blood vessel. 

Splenectomy 

Splenectomy is a surgical removal of the spleen. The spleen is known to store over 1 in 3 amounts of platelets in the body. In some cases of thrombocytopenia, the spleen is responsible for abnormal platelet accumulation and destruction, e.g., immune thrombocytopenic purpura (ITP). It is suggested that spleen removal can help restore platelets into the blood circulation. However, there are possible complications involved with the procedure including bleeding, infection, and abnormal blood clots. Vaccinations may be offered to minimise the risk of infections. 

Lifestyle modifications 

Thrombocytopenia increases the risk of bleeding easily with reduced ability to heal properly. There are some precautions you can take to minimise complications, such as:^2,4,8

• Maintaining good oral hygiene and using soft toothbrushes to prevent gum bleeding. 
• Avoid activities that may increase the risk of injury or bleeding, e.g., contact sports like rugby. You can discuss with your healthcare advisor what activities are suitable without increasing your risk of injury. 
• Avoiding alcohol. 
• Avoiding smoking. 
• Wearing appropriate safety gear when needed.
• Discuss with your healthcare advisor before using other medications or supplements.

Monitoring

Regular monitoring of platelet counts through blood tests is essential to track progress and adjust treatment as needed. 

Preventing thrombocytopenia

It is important to understand and monitor if you have any underlying medical conditions or are taking any medications that can increase your risk of developing thrombocytopenia. There are lifestyle choices that you can adjust to minimise your risks of thrombocytopenia.⁸  

• Regular health check-ups and monitoring - particularly if you have medical conditions like chronic liver disease or autoimmune disorders. 
• Immunisation or vaccination - against infections like hepatitis or HIV. 
• Medication management - such as certain antibiotics or chemotherapies. 
• Maintaining a healthy diet and nutrition - ensuring sufficient levels of iron, vitamin B12 and folate.
• Stress management - high levels of stress can weaken our immune system. 
• Pregnancy management - regular check-ups with your healthcare provider. 
• Avoiding environmental toxins.
• Safety precautions - wear safety gear when needed.  

Summary

The underlying cause of thrombocytopenia must be identified to form the most appropriate treatment. The choice of treatment will depend on several factors, including the cause, severity, and overall individual. Please consult with your healthcare provider for up-to-date and tailored medical guidance. Early diagnosis and treatment are important to help manage this condition and prevent complications associated with bleeding disorders.