§ Erythrocytosis
Erythrocytosis is a laboratory finding in which there is an increased number of red blood cells (RBC), along with an accompanying increase in the concentration of hemoglobin in the peripheral blood. In absolute polycythemia (also called erythrocytosis) there is an increased RCM. Patients are further categorized into primary and secondary forms. Primary polycythemia is caused by an acquired or inherited mutation leading to an abnormality within RBC progenitors; it includes polycythemia vera (PV) and rare familial variants. Secondary polycythemia is caused by a circulating factor stimulating erythropoiesis, usually erythropoietin (Epo). It is most often due to an Epo response to hypoxia, but can also result from an Epo-secreting tumor.
Lab tests:
CBC and Automated Differential
Blood Smear with Interpretation
Reticulocyte count
Blood volume measurement
Serum erythropoietin
JAK2 mutation testing
Bone marrow aspiration and biopsy
References:
- oung NS, Bacigalupo A, Marsh JC. Aplastic anemia: pathophysiology and treatment. Biol Blood Marrow Transplant 2010; 16:S119.
- Guinan EC. Acquired aplastic anemia in childhood. Hematol Oncol Clin North Am 2009; 23:171.
- Mehta, Paulette. “Wintrobe’s Clinical Hematology.” JAMA 302.22 (2009): 2488-2493.
