From the Guidelines
Thrombocytopenia is primarily caused by decreased production, increased destruction, or abnormal sequestration of platelets, with immune thrombocytopenia (ITP) being a common cause of increased destruction, as noted in the 2019 American Society of Hematology guidelines 1. The causes of thrombocytopenia can be broadly categorized into these three mechanisms. Decreased production occurs in conditions like bone marrow failure syndromes, leukemia, myelodysplastic syndromes, vitamin B12 or folate deficiency, and as a side effect of chemotherapy or radiation therapy. Increased destruction happens in immune thrombocytopenia (ITP), thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), disseminated intravascular coagulation (DIC), and drug-induced immune reactions. Common medications that can cause thrombocytopenia include heparin, quinine, sulfonamides, and certain antibiotics, as highlighted in a study from 1996 1. Sequestration occurs when platelets are trapped in an enlarged spleen (hypersplenism) due to liver cirrhosis or portal hypertension. Pregnancy-related conditions like preeclampsia and HELLP syndrome can also cause thrombocytopenia. Viral infections including HIV, hepatitis C, and COVID-19 may reduce platelet counts through various mechanisms. Identifying the underlying cause is crucial for appropriate management, which may range from observation to medication adjustments, immunosuppressive therapy, or platelet transfusions depending on the severity and etiology, with guidelines suggesting a threshold for prophylactic transfusion in patients with solid tumors 1. Key considerations in managing thrombocytopenia include the patient's overall health, the presence of bleeding symptoms, and the risk of major bleeding, as emphasized in the 2019 guidelines 1. The most recent and highest quality evidence, as seen in the 2019 American Society of Hematology guidelines 1, prioritizes the identification of the underlying cause of thrombocytopenia to guide management decisions, emphasizing the importance of a thorough diagnostic evaluation. In clinical practice, the management of thrombocytopenia should be individualized based on the specific cause, severity, and patient factors, with a focus on minimizing the risk of bleeding and improving quality of life, as noted in the guidelines 1. Overall, the causes of thrombocytopenia are diverse, and a comprehensive approach to diagnosis and management is essential to optimize patient outcomes, as supported by the evidence from the American Society of Hematology guidelines 1.
From the Research
Causes of Thrombocytopenia
Thrombocytopenia can occur due to various reasons, including:
- Decreased platelet production 2, 3, 4, 5
- Increased platelet destruction 2, 3, 4, 5
- Splenic sequestration 2, 4, 5
- Dilution or clumping 2
- Vitamin B12 deficiency 6
- Infections 4
- Malignancy 4
- Liver disease 2, 4
- Autoimmune disorders 2, 3, 4
- Disseminated intravascular coagulation 4
- Pregnancy 4
- Medications 2, 4
- Coagulation disorders 4
Specific Causes
Some specific causes of thrombocytopenia include: