hematology and oncology
Secondary Erythrocytosis
Evaluation of Secondary Erythrocytosis
Tests done when isolated erythrocytosis is present include Arterial oxygen saturation Serumerythropoietinlevels P50 to rule out a high oxygen-affinity hemoglobinopathy level is diagnostically nonspecific. If polycythemia vera is suspected, the patient should be evaluated as for Diagnosis . Serumerythropoietinlevel is elevated in patients with hypoxia-induced erythrocytosis (or level is inappropriately normal for their elevated hematocrit) and in patients with tumor-associated erythrocytosis. Patients with elevatederythropoietinlevels (and no indication of hypoxia) or microscopic hematuria should undergo abdominal imaging, central nervous system imaging, or both to seek a renal lesion or other tumor sources oferythropoietin. P50 measures the affinity of hemoglobin for oxygen; a normal result excludes a high oxygen-affinity hemoglobinopathy (a familial abnormality) as the cause of erythrocytosis. 