<prompt> Most significant complication of polycythemia rubra vera is:Transformation into leukemiaSecondary bone marrow failureHypersplenismThrombosis  <response>: Polycythemia rubra vera It is an indolent disorder Thrombosis is the most significant complication Maintenance of the hemoglobin level at 140 gL 14 gdL; hematocrit Phlebotomy :serves to help this aim Ref: Harrison, E-18,P-903 