Polycythemia vera is absolute venous hematocrit of > -

Ans. is 'b' i.e., 55% Diagnosis of polycythemiaHematocrito The hematocrit (HCT) is expressed as the percent of a blood occupied by intact RBC's.o Polycy'themia in the adult patient is suspected when the hematocrit is> 48% in women> 52% in menHemoeiobin concentrationo The hemoglobin concentration (HGB) is its content in grams/100 ml of whole blood. Polycythemia in the adult is suspected when the hemoglobin is>16.5% in women> 18.5% in menRed blood cell counto The red blood cell count is expressed as the number of RBC per microl or L of whole blood,o It is least often used to suggest polycythemia since patients with thalassemia minor may have an elevated RBC count but a normal or reduced hematocrit or hemoglobin due to presence of small (microcytic) poorly hemoglobinized (hypochromid red cells).o Once a high value has been reported it should be confirmed by repeat testing to rule out lab error.o An accurate history and physical examination is critical in order to determine the etiology of polycythemia.o The most common cause of polycythemia is hypoxia secondary to pulmonary disease as a result pertaining eliciting symptoms pertaining to altered lung function.The 2008 WHO diagnostic criteria for polycythemia vera: -MAJOR CRITERIAo Hb > 18.59/dl (men) > 16.5 g/'dl (women)oro Hb or Hct > 99,h percentile of reference for age, sex or altitude of residenceoro Hb> 17g/dl (men)o Hb > 15g;dl (women)If associated with a sustained increase of 129 gdl fronts baseline that cannot be attributed to correction of iron defic iencyoro Elevated red cell mass > 25% above mean normal predicted valueo Presence of JAK 2V617F or similar mutationMINOR CRITERIAo Bone marrow biopsy showing trilineage myeloproliferationo Subnormal serum ervthropoieten level EFC growth