Common causes of secondary erythrocytosis include Smoking Chronic arterial hypoxemia Tumors (tumor-associated erythrocytosis) Use of androgenic steroids Surreptitious erythropoietin use Less common causes include certain congenital disorders such as High oxygen-affinity hemoglobinopathies Erythropoietin receptor mutations Chuvash polycythemia (in which a mutation in the VHL gene affects the hypoxia-sensing pathway) Right to left arteriovenous shunts in the lungs Proline hydroxylase 2 and hypoxia-inducible factor 2 alpha (HIF-2α) mutations Spurious erythrocytosis may occur with hemoconcentration (eg, due to burns, diarrhea, or diuretic use).