Polycythemia Vera

Red cell mass

• • Normal → Low plasma volume
• • Low → Heart, Lung, Kidney, CNS, other cause
• • Elevated → evaluate Arterial O2

Elevated red cell mass — Arterial O2

• Normal → COHgb: • High → Smoke exposure • Normal → CT scan head, abdomen

CT scan head, abdomen

• • Positive (+) → Hemoglobin studies: - Abnormal → High O2 affinity hemoglobin, 2,3-DPG deficiency - Normal → Erythropoietin
• • Negative (-) → Heart, Lung, Kidney, CNS, other cause

Erythropoietin

• • Elevated → Heart, Lung, Kidney, CNS, other cause
• • Low → Rule out polycythemia vera: CBC, differential; Bone marrow with chromosomes; Leukocyte alkaline phosphatase; B12/B12 binding capacity; JAK2 mutation - Normal → von Hippel-Lindau mutations, Erythropoietin receptor mutations, Other causes