The investigation of thrombocytopenia is made difficult by the multitude of differential diagnoses to consider and the frequent need for urgency in arriving at this diagnosis.
- The diagnosis of thrombocytopenia needs to be confirmed by repeating the platelet count and excluding platelet clumps on blood film examination.
- Patients should be assessed for active bleeding and, if present, they should be referred to hospital immediately.
- Thrombocytopenia is commonly associated with a mucocutaneous bleeding pattern.
- Thrombocytopenia is due to reduced platelet production, increased platelet destruction or increased platelet sequestration.
- Immune thrombocytopenia is recognised as a disorder of both increased platelet destruction and inadequate platelet production.
- Prophylactic platelet transfusion is usually only needed when the platelet count is less than 10 x 109/L.
- Investigations should be directed by the clinical context because of the wide range of causes of thrombocytopenia.