From the Guidelines
Thrombocytopenia, or low platelet count, can be caused by a variety of factors including bone marrow disorders, increased platelet destruction, medication side effects, and certain medical conditions, as noted in a study published in 2010 1.
Causes of Thrombocytopenia
The causes of thrombocytopenia are diverse and can be categorized into several groups:
- Bone marrow disorders such as leukemia, aplastic anemia, or vitamin deficiencies can reduce platelet production.
- Autoimmune conditions like immune thrombocytopenic purpura (ITP) cause the immune system to destroy platelets, as discussed in a consensus report on ITP published in 2010 1.
- Medications including heparin, quinine, sulfonamides, and certain antibiotics can trigger low platelet counts, with heparin-induced thrombocytopenia (HIT) being a significant concern, as outlined in a 2020 study on the diagnosis and management of HIT 1.
- Other causes include viral infections (HIV, hepatitis C), bacterial infections (sepsis), pregnancy complications, alcohol abuse, and enlarged spleen.
- Chemotherapy and radiation therapy also commonly reduce platelet production.
- Genetic disorders like Wiskott-Aldrich syndrome and May-Hegglin anomaly can cause inherited thrombocytopenia.
Importance of Identifying the Underlying Cause
Identifying and addressing the underlying cause of thrombocytopenia is crucial for effective management, as stopping problematic medications, treating infections, or using medications to boost platelet production can significantly improve outcomes. Severe cases might require platelet transfusions, especially when counts fall below 10,000 per microliter or if there's active bleeding. Given the complexity and potential severity of thrombocytopenia, a thorough diagnostic approach and timely intervention are essential to prevent morbidity and mortality, as emphasized by the most recent and highest quality study available 1.
From the FDA Drug Label
Heparin-induced thrombocytopenia (HIT) is a serious antibody-mediated reaction. HIT occurs in patients treated with heparin and is due to the development of antibodies to a platelet Factor 4-heparin complex that induce in vivo platelet aggregation Thrombocytopenia in patients receiving heparin has been reported at frequencies up to 30%. It can occur 2 to 20 days (average 5 to 9) following the onset of heparin therapy.
Thrombocytopenia (low platelet count) can be caused by heparin-induced thrombocytopenia (HIT), a serious antibody-mediated reaction that occurs in patients treated with heparin. This condition is due to the development of antibodies to a platelet Factor 4-heparin complex that induce in vivo platelet aggregation. Thrombocytopenia can occur in up to 30% of patients receiving heparin, typically within 2 to 20 days after starting heparin therapy 2.
From the Research
Causes of Thrombocytopenia
- Decreased platelet production 3, 4, 5
- Increased destruction of platelets 3, 4, 5, 6
- Splenic sequestration 3, 5
- Dilution or clumping of platelets 3
- Infections 4
- Malignancy 4
- Liver disease 4, 5
- Autoimmune disorders 4, 6
- Disseminated intravascular coagulation 4
- Pregnancy 4, 7
- Medications 3, 4, 6
- Coagulation disorders 4
- Bone marrow insufficiency with impaired platelet production 5
- Activation of the clotting cascade 5
- Platelet binding antibodies 5
- Sepsis 5
- Chronic alcohol abuse 5
- Liver cirrhosis 5
Clinical Presentation
- Asymptomatic with platelet count greater than 50 × 10^3 per μL 3
- Mild skin manifestations such as petechiae, purpura, or ecchymosis with platelet counts between 20 and 50 × 10^3 per μL 3
- High risk of serious bleeding with platelet counts of less than 10 × 10^3 per μL 3
- Organ failure and adverse prognosis with moderate-degree thrombocytopenia 7