What are the causes of thrombocytopenia (low platelet count)?

From the Guidelines

Thrombocytopenia should be managed based on the severity, cause, and symptoms, with first-line treatment for immune thrombocytopenia (ITP) typically including corticosteroids such as prednisone or dexamethasone, as recommended by the American Society of Hematology 2019 guidelines 1.

Treatment Approach

The treatment approach for thrombocytopenia depends on the underlying cause, with ITP being a common cause of thrombocytopenia. According to the American Society of Hematology 2019 guidelines 1, first-line treatment for ITP typically includes corticosteroids such as prednisone (1 mg/kg/day for 2-4 weeks, followed by tapering) or dexamethasone (40 mg daily for 4 days).

• For acute severe thrombocytopenia with bleeding, intravenous immunoglobulin (IVIG) at 1 g/kg for 1-2 days may be used.
• Second-line options include thrombopoietin receptor agonists like eltrombopag (starting at 50 mg daily) or romiplostim (1 μg/kg weekly, subcutaneously).
• Rituximab (375 mg/m² weekly for 4 weeks) may be considered for refractory cases.

Management Considerations

• Platelet transfusions are generally reserved for severe thrombocytopenia (<10,000 platelets/μL) with active bleeding or before procedures.
• Patients should avoid medications that affect platelet function (aspirin, NSAIDs) and activities with high bleeding risk.
• The decision to treat and the choice of therapy should be individualized based on the patient's risk of bleeding, comorbidities, and preferences, as well as the potential benefits and risks of treatment, as noted in the international consensus report on the investigation and management of primary immune thrombocytopenia 1.

Quality of Life and Morbidity

• Thrombocytopenia can have a significant impact on health-related quality of life (HRQoL), particularly in the first year after diagnosis, related to restrictions on activities, anxiety due to the risk of bleeding, and the burden of treatment and monitoring, as reported in the American Society of Hematology 2019 guidelines 1.
• Fatigue is common and reported in 22% to 45% of patients with ITP.
• The effect of treatment on HRQoL and fatigue may vary by treatment, but this area requires further study.

From the FDA Drug Label

Nplate is a thrombopoietin receptor agonist indicated for the treatment of thrombocytopenia in: Adult patients with immune thrombocytopenia (ITP) who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy. Pediatric patients 1 year of age and older with ITP for at least 6 months who have had an insufficient response to corticosteroids, immunoglobulins, or splenectomy. ALVAIZ is a prescription medicine used to treat: adults and children 6 years of age and older with low blood platelet counts due to persistent or chronic immune thrombocytopenia (ITP), when other medicines to treat ITP or surgery to remove the spleen have not worked well enough

Thrombocytopenia Treatment:

• Romiplostim (Nplate) and eltrombopag (ALVAIZ) are indicated for the treatment of thrombocytopenia in patients with immune thrombocytopenia (ITP) who have had an insufficient response to other treatments.
• These medications are used to increase platelet counts and reduce the risk of bleeding.
• The dosage and administration of these medications vary depending on the patient's condition and response to treatment 2, 3.
• It is essential to follow the recommended dosage and administration instructions to minimize the risk of adverse reactions.
• Patients should be monitored regularly for changes in platelet counts and potential side effects.
• Key points to consider when treating thrombocytopenia with these medications include:
  • Patient selection: Romiplostim and eltrombopag are indicated for patients with ITP who have had an insufficient response to other treatments.
  • Dosing: The dosage of these medications should be adjusted based on the patient's platelet response.
  • Monitoring: Patients should be monitored regularly for changes in platelet counts and potential side effects.

From the Research

Definition and Classification of Thrombocytopenia

• Thrombocytopenia is defined as a platelet count of less than 150 × 10^3 per μL 4
• It can occur due to decreased platelet production, increased destruction, splenic sequestration, or dilution or clumping 4

Clinical Presentation of Thrombocytopenia

• Patients with a platelet count greater than 50 × 10^3 per μL are generally asymptomatic 4
• Patients with platelet counts between 20 and 50 × 10^3 per μL may have mild skin manifestations such as petechiae, purpura, or ecchymosis 4
• Patients with platelet counts of less than 10 × 10^3 per μL have a high risk of serious bleeding 4

Diagnosis and Evaluation of Thrombocytopenia

• The first step in evaluating thrombocytopenia is to exclude pseudothrombocytopenia by collecting blood in a tube containing heparin or sodium citrate and repeating the platelet count 4
• Examination of the blood film is essential in the investigation of any patient with thrombocytopenia 5
• The context in which thrombocytopenia occurred, its severity, timing, and association with bleeding are important clues to the diagnosis 5

Treatment and Management of Thrombocytopenia

• Transfusion of platelets is recommended when patients have active hemorrhage or when platelet counts are less than 10 × 10^3 per μL, in addition to treatment of underlying causative conditions 4
• Patients with platelet counts of less than 50 × 10^3 per μL should adhere to activity restrictions to avoid trauma-associated bleeding 4
• Immune thrombocytopenia (ITP) is an autoimmune disease characterized by platelet destruction and reduced platelet production, and its treatment options include corticosteroids, intravenous immunoglobulins, and novel drugs such as thrombopoietin receptor agonists and rituximab 6, 7

Special Considerations in Thrombocytopenia

• Thrombocytopenia does not protect against thrombosis, and antithrombotic therapy is often required for patients despite very low platelet counts 5
• Antithrombotic therapy should not be withheld because of thrombocytopenia alone 5
• Splenectomy is frequently deferred in modern ITP treatment algorithms, and medical therapies such as thrombopoietin receptor agonists and rituximab are preferred 7