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For further information, see CMDT Part 13-24: Polycythemia Vera
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Essentials of Diagnosis
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Elevated hematocrit (Hct) and/or hemoglobin
Usually elevated white blood count (WBC) and platelet count
JAK2 V617F mutation
Splenomegaly
Normal arterial oxygen saturation
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General Considerations
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Common complaints related to expanded blood volume and increased blood viscosity include
Headache
Dizziness
Tinnitus
Blurred vision
Fatigue
Generalized pruritus is related to histamine release from basophils
Epistaxis is probably related to engorgement of mucosal blood vessels in combination with abnormal hemostasis
Thrombosis
Appears to be related both to increased blood viscosity and abnormal platelet function
Incidence of thrombotic complications from surgery is very high if polycythemia is uncontrolled; elective surgery should be deferred until the condition has been treated
Increased bleeding can also occur
Physical examination reveals plethora and engorged retinal veins
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Differential Diagnosis
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Spurious polycythemia may be related to diuretic use or may occur without obvious cause
Suspect a secondary cause of polycythemia if
Secondary causes of polycythemia include
Hypoxia: cardiac disease, pulmonary disease, high altitude
Carboxyhemoglobin: smoking
Kidney lesions
Erythropoietin-secreting tumors (rare)
Abnormal hemoglobins (rare)
Polycythemia vera should be differentiated from other myeloproliferative disorders (Table 13–14)
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