Medical Term for Low Platelets
The medical term for low platelets is thrombocytopenia, defined as a peripheral blood platelet count less than 150 × 10⁹/L (or 150,000/μL). 1, 2
Definition and Thresholds
- Thrombocytopenia is universally defined as a platelet count below 150 × 10⁹/L 1, 2, 3
- This represents the standard diagnostic threshold across all major hematology guidelines 1
Clinical Significance by Severity
The severity of thrombocytopenia determines bleeding risk and clinical management:
Mild Thrombocytopenia (>50 × 10⁹/L)
- Patients are generally asymptomatic with minimal bleeding risk 2
- Spontaneous serious bleeding is rare (<5% of patients) 4
- Most procedures can be performed safely without platelet transfusion 4
Moderate Thrombocytopenia (20-50 × 10⁹/L)
- Patients may develop mild skin manifestations including petechiae, purpura, or ecchymosis 2
- Outpatient management is generally appropriate in the absence of significant bleeding 4
- Expedited hematology follow-up within 24-72 hours is recommended 4
Severe Thrombocytopenia (<20 × 10⁹/L)
- Hospital admission should be considered for newly diagnosed patients 4
- The risk of spontaneous intracranial hemorrhage becomes significant at counts <20 × 10⁹/L 4
Critical Thrombocytopenia (<10 × 10⁹/L)
- High risk of serious bleeding complications 2
- Prophylactic platelet transfusion is recommended at this threshold for patients with therapy-induced hypoproliferative thrombocytopenia 1
Important Terminology Distinctions
When thrombocytopenia occurs due to immune-mediated destruction, it may be specifically termed:
- Immune thrombocytopenia (ITP): The current preferred term for immune-mediated thrombocytopenia 1
- The older term "idiopathic thrombocytopenic purpura" has been revised because many patients lack purpura (bleeding into skin) and the immune mechanism is now understood 1
Common Pitfall
Pseudothrombocytopenia must be excluded before confirming true thrombocytopenia, as platelet clumping in EDTA tubes occurs in approximately 0.1% of adults and can falsely lower platelet counts 4. This requires peripheral blood smear examination or recollection in heparin or sodium citrate tubes 4, 2.