Spurious polycythaemia--a study of 35 patients.

A study of 35 patients with elevated Hb and haematocrit but normal or borderline red cell mass has confirmed that the most common disease association was hypertension and that the peripheral blood findings are reversible when blood pressure is treated, especially when the body haematocrit is low. The situation is probably the result of abnormal distribution of red cells in the circulation. The red cell pool in these patients is normal and they show no evidence of progression to polycythaemia vera. Some cases are associated with smoking and obesity. It is more rational to treat the underlying disease than to attempt to alter the blood volume by venesection.