Polycythaemia

DGRefHelp - NHS Dumfries & Galloway
NHS Dumfries and Galloway

Polycythaemia is characterised by

  • elevated haemoglobin > 180g/L (males), > 165 (females) and/or
  • rise in Haematocrit > 0.52  (males), >0.45 (females).

Causes

  • Primary: Myeloproliferative Neoplasia – Primary Polycythaemia
  • Secondary (true): hypoxaemia (cyanotic heart disease, chronic lung disease, OSA), Erythropoietin-secreting tumours / renal cyst
  • Relative Polycythaemia resulting from reduced plasma volume - diuresis

Assessment

Assess

  • Alcohol/smoking
  • History suggestive of sleep apnoea (although this is a rare cause of polycythaemia)
  • Illicit drug/food supplements
  • For signs chronic lung disease including O2 sats
  • Examine for splenomegaly

Investigations

  • Repeat FBC ensuring good hydration

Primary care management

Advise about lifestyle factors.

Individuals with mild idiopathic erythrocytosis who do not require venesection / intervention and show stable red cell indices can be followed up in primary care with a blood count check every 6-12 months (individual monitoring plan).

Discuss referral to haematology if there is steady rise in red cell indices or suspicious symptoms

Who to refer

Urgent referral

  • Very high Haematocrit; > 0.6 in males, > 0.56 in females
  • Raised Haematocrit in association with acute arterial or venous thrombotic event or active neurological symptoms (persistent headache, visual impairment, TIA)

Routine referral or advice request

  • Relatively raised Haematocrit in association with; splenomegaly, unexplained pruritis
  • Concomitant unexplained increase in white cell count of platelet count
  • Persistent unexplained rise in Haematocrit; > 0.52 in males, > 0.46 in females

Editorial Information

Last reviewed: 01/10/2024

Next review date: 01/10/2026

Author(s): Muayed Lasebai, Ranjit Thomas, Paul Ames.

Version: 1.0