Guideline sources The following summarized guidelines for the evaluation and management of polycythemia are prepared by our editorial team based on guidelines from the British Society for Haematology (BSH 2005). 1 Pathway Polycythemia Evaluation and management Guidelines 1. Screening and diagnosis Diagnostic criteria: confirm polycythemia by demonstrating a persistently elevated hematocrit on at least 2 measurements over a 3-month period. 2. Diagnostic investigations https://web.pathway.md/diseases/recW90YIhUMdzAXTB 1/3 6/29/23, 11:17 PM Polycythemia Pathway Identification of comorbidities: screen for hypertension, dyslipidemia, diabetes, and tobacco use. Thrombophilic workup: evidence is lacking to support routine thrombophilia screening in polycythemia vera. B 3. Medical management Management of apparent erythrocytosis: advise a reduction or elimination of factors which may contribute to apparent erythrocytosis, such as a reduction in smoking and alcohol intake and control of hypertension (without the use of a thiazide diuretic). B Show 2 more Management of polycythemia vera: perform venesection to target a reduction in hematocrit to < 45%. B Show 2 more Updated evidence: CYTO-PV In adults patients with JAK2-positive polycythemia vera who were being treated with phlebotomy, hydroxyurea, or both, low-hematocrit targeted therapy was superior to high- hematocrit targeted therapy with respect to death from cardiovascular causes or major thrombotic events. Marchioli R et al. N Engl J Med. 2013 Jan 3. Management of idiopathic erythrocytosis: initiate venesection to reduce the hematocrit to < 0.45 in patients with idiopathic erythrocytosis and a hematocrit > 0.54. B Show 5 more Management of high affinity hemoglobins: Consider venesection for high affinity Hgbs in patients with symptoms of polycythemia, thrombosis, or a history of thrombosis in a family member affected by the disease with comparable thrombotic risk profile. Consider targeting a hematocrit < 0.60 in patients managed with venesection, rather than targeting a normal hematocrit. 4. Nonpharmacologic interventions Smoking cessation: manage conventional risk factors for atherosclerosis aggressively, and advise all patients to stop smoking. B 5. Specific circumstances Patients with pulmonary disease: https://web.pathway.md/diseases/recW90YIhUMdzAXTB 2/3 6/29/23, 11:17 PM Polycythemia Pathway Refer to a respirology specialist for consideration of long-term oxygen therapy and other thrapies. A Consider ACEIs or ARBs in patients who do not tolerate venesection, based on limited evidence. C Patients with cyanotic heart disease: Manage patients with cyanotic congenital heart disease and an erythrocytosis in a specialized congenital heart disease unit. B Perform isovolumic venesection when the patient has symptoms of hyperviscosity; no general target Hct can be suggested and treatment should be individualized. B Patients post renal transplantation: counsel patients to maintain adequate fluid intake in order to avoid dehydration. Show 2 more Clinical findings Symptoms Past medical history Abdominal discomfort COPD Confusion DVT Dizziness Gout Fatigue Kidney cancer Headache PE Itching Sleep apnea Vital signs Integument exam Hypertension Bruises Genetic testing Jak2 gene mutation Studies 2013 CYTO-PV In adults patients with JAK2-positive polycythemia vera who were being treated with phlebotomy, hydroxyurea, or both, low-hematocrit targeted therapy was superior to high-hematocrit targeted therapy with respect to death from cardiovascular causes or major thrombotic events. Marchioli R et al. N Engl J Med. 2013 Jan 3. References 1. McMullin MF, Bareford D, Campbell P et al. Guidelines for the diagnosis, investigation and management of polycythaemia/erythrocytosis. Br J Haematol. 2005 Jul;130 2 174 95. Open https://web.pathway.md/diseases/recW90YIhUMdzAXTB 3/3