The role of serum erythropoietin level and jak2 v617f allele burden in the diagnosis of polycythaemia vera

Summary Low serum erythropoietin ( EPO ) is a minor criterion of Polycythaemia Vera ( PV ) but its diagnostic usefulness relies on studies performed before the discovery of JAK 2 V617F mutation. The objective of the present study was to evaluate the diagnostic accuracy of serum EPO and JAK 2 V617F allele burden as markers of PV as well as the combination of different diagnostic criteria in 287 patients (99 with PV , 137 with Essential Thrombocythaemia and 51 with non‐clonal erythrocytosis). Low EPO showed good diagnostic accuracy as a marker for PV , with the area under the curve ( AUC ) of the chemiluminescent‐enhanced enzyme immunoassay ( CEIA ) being better than that of radioimmunoassay ( RIA ) (0·87 and 0·76 for CEIA and RIA , respectively). JAK 2 V617F quantification displayed an excellent diagnostic accuracy, with an AUC of 0·95. A haematocrit >52% (males) or >48% (females) plus the presence of the JAK 2 V617F mutation had a sensitivity and specificity of 79% and 97%, respectively. Adding low EPO or the JAK 2 V617F allele burden did not improve the diagnostic accuracy for PV whereas the inclusion of both improved the sensitivity up to 83% and maintaining 96% specificity. Haematocrit and qualitative JAK 2 V617F mutation allow a reliable diagnosis of PV . Incorporation of EPO and/or JAK 2 V617F mutant load does not improve the diagnostic accuracy.