<prompt> Most common post operative complication in polycythemia vera-InfectionCardiopulmonary complicationHemolysisUremia  <response>: Increased risk of urate stones and gout due to hyperuricemia is seen in polycythemia vera. Relative Reduced plasma volume hemoconcentration Absolute Primary Abnormal proliferation of myeloid stem cells, normal or low erythropoietin levels polycythemia vera; inherited activating mutations in the erythropoietin receptor rare 2.secondary Increased erythropoietin levels Adaptive: lung disease, high-altitude living, cyanotic hea disease Paraneoplastic: erythropoietin-secreting tumors e.g., renal cell carcinoma, hepatomacellular carcinoma, cerebellar hemangioblastoma Surreptitious: endurance athletes Reference :textbook of Pathology ,author Harsha Mohan 7th edition page number 339 RefRobbins 9e pg 425 