Differential Diagnosis ARCILLA, Juan Martin E.

Causes of Erythrocytosis Relative Erythrocytosis: Hemoconcentration secondary to dehydration, androgens, or tobaco abuse Absolute Erythrocytosis: Hypoxia Carbon monoxide intoxication High affinity hemoglobin High altitude Pulmonary disease R-L shunts Sleep apnea syndrome Neurologic disease Renal disease Renal artery stenosis Focal sclerosing or membranous glomerulonephritis Renal transplantation Tumors Hypernephroma Hepatoma Cerebellar hemangioblastoma Uterine fibromyoma Drugs Androgens Recombinant erythropoietin Familial (with normal Hgb function, Chuvash, erythropoietin receptor mutations)

Absolute polycythemia vera apparent polycythemia vera Either a clonal myeloproliferative disorder (polycythemia vera) or a nonclonal increase in red blood cell mass that is often mediated by erythropoietin (secondary polycythemia) Either a decrease in plasma volume (relative polycythemia) or a misperception of what constitutes the upper limit of normal values for either hemoglobin or hematocrit

Apparent Polycythemia Relative Polycythemia conditions that cause acute depletion of volume e.g., severe dehydration, diarrhea, vomiting, use of diuretics, capillary leak syndrome, severe burns the existence of chronic contraction of the plasma volume Gaisbock’s syndrome Stress/spurious polycythemia

Absolute Polycythemia Polycythemia vera Secondary polycythemia Congenital Associated with high or normal serum erythropoietin level    Associated with low serum erythropoietin level Acquired Erythropoietin mediated Hypoxia-driven Hypoxia-independent (pathologic erythropoietin production) Drug associated Unknown mechanism

Secondary Polycythemia Congenital Associated with high or normal serum erythropoietin level    Chuvash and other polycythemias associated with von values Hippel-Lindau (VHL) gene mutation High–oxygen affinity hemoglobinopathy 2,3-Diphosphoglycerate mutase deficiency Associated with low serum erythropoietin level Activating mutation of the erythropoietin receptor

Secondary Polycythemia Acquired Erythropoietin mediated Hypoxia-driven

Acquired Secondary Polycythemia Erythropoietin mediated Hypoxia-driven Central hypoxic process Chronic lung disease Right-to-left cardiopulmonary vascular shunts High-altitude habitat Carbon monoxide poisoning Smoker's polycythemia (chronic carbon monoxide exposure) Hypoventilation syndromes including sleep apnea Peripheral hypoxic process   Localized Renal artery stenosis    Hypoxia-independent

Secondary Polycythemia Acquired Erythropoietin mediated Hypoxia-independent (pathologic erythropoietin production)

Acquired Secondary Polycythemia Erythropoietin mediated Hypoxia-driven  Hypoxia-independent (pathologic erythropoietin production) Malignant tumors   HCC Renal cell cancer   Cerebellar hemangioblastoma   Parathyroid carcinoma   Nonmalignant conditions Uterine leiomyomas    Renal cysts (polycystic kidney disease) Pheochromocytoma Meningioma   

Secondary Polycythemia Acquired Drug associated Erythropoietin doping Treatment with androgen preparations

Secondary Polycythemia Acquired Unknown mechanism Post–renal transplant erythrocytosis