Laboratory Aspect of Primary Polycythemia (PV)

الملخص

Polycythemia or erythrocytosis is an increase in red blood cell mass. There is an increase in the concentration of red blood cells and hemoglobin in the blood. Primary polycythemias are caused by acquired or inherited mutations that cause functional changes in hematopoietic stem cells or erythroid progenitors resulting in accumulation of red blood cells. Common primary polycythemias include: Polycythemia Vera (PV), which is a clonal disorder. The assessment steps for polycythemia require the patient's clinical history and complete blood count (CBC) results, Erythropoietin (Epo) levels to determine the cause of erythrocytosis, and molecular analysis of JAK2 mutations to evaluate Polycythemia vera. Patients with clinical suspicion of congenital erythrocytosis need mutational analysis as a confirmatory test. The development of molecular tests for mutations associated with polycythemia can establish a clearer classification and etiology. The JAK2 V617F mutation is most common in PV (>95%) and is present in the majority of PMF and ET (50% to 60%). Various methods have been advocated for the detection of JAK2 V617F, including high-resolution PCR product melting curve analysis, Sanger sequencing or pyrosequencing, and allele-specific PCR variants (eg, amplification refractory mutation system [ARMS] and RQ-PCR). Of these, the allele-specific PCR approach using DNA as a template reproducibly achieves the highest analytical sensitivity.