1. Differential Diagnosis
ARCILLA, Juan Martin E.

2. 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)

3. 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

4. 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

5. 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

6. 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

7. Secondary Polycythemia
Acquired
Erythropoietin mediated
Hypoxia-driven

8. 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

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

10. 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   

11. Secondary Polycythemia
Acquired
Drug associated
Erythropoietin doping
Treatment with androgen preparations

12. Secondary Polycythemia
Acquired
Unknown mechanism
Post–renal transplant erythrocytosis