When should I consider referring a patient with thrombocytopenia to a haematologist?

Consider referring a patient with thrombocytopenia to a haematologist in the following situations:

• If the platelet count is less than 20 × 10⁹/L or if there is active bleeding, arrange immediate referral or seek urgent specialist advice for direct assessment, due to the high risk of spontaneous haemorrhage.
• If the platelet count is less than 50 × 10⁹/L, arrange urgent referral to haematology.
• If the platelet count is between 50 and 100 × 10⁹/L, arrange urgent referral if associated with pancytopenia (haemoglobin <100 g/L, neutrophils <1 × 10⁹/L), splenomegaly or lymphadenopathy, pregnancy, or upcoming surgical/interventional procedures.
• If the platelet count is less than 100 × 10⁹/L and thrombocytopenia is persistent and unexplained on at least two occasions 4–6 weeks apart, refer to haematology according to local guidelines.
• If there is a lowering platelet count trend, other haematological abnormalities, or the patient is unwell, consider referral.
• For patients with suspected cancer and thrombocytopenia, refer urgently via the suspected cancer pathway.

For patients with a known underlying cause or drug-induced thrombocytopenia, manage according to local guidelines and consider stopping the causative drug with monitoring before referral.

In children and adults with abnormal bruising and low platelet count or abnormal clotting screen, referral to haematology is also indicated.

These referral criteria help ensure timely specialist assessment to diagnose and manage potentially serious causes of thrombocytopenia.

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