The diagnosis and management of erythrocytosis

Summary points

• Erythrocytosis is a common reason for referral to haematology services and is usually secondary in origin

• Referral thresholds for iron replete patients are packed cell volume persistently >0.52 in men and >0.48 in women

• The cause can often be elucidated from a detailed medical and drug history

• Common secondary causes include smoking, hypoxia, and diuretics

• Intervention is not always indicated, and the decision to venesect is often made on a case by case basis after a risk-benefit assessment

• True polycythaemia vera is rare. It carries an increased risk of thrombosis and progression to myelofibrosis or leukaemia and requires specialist management

Sources and selection criteria

We searched PubMed to identify peer reviewed original articles, meta-analyses, and reviews. We considered only those papers that were written in English, published from 1966 until the present day, which described studies that had adequate scientific validity. The authors’ own collections and older references generated from initial papers were also examined. Randomised trials and series of patients and single case reports were considered if appropriate.