- 1 Primary polycythemia results from functional abnormalities intrinsic to erythroid progenitors, causing them to be hypersensitive to or independent of erythropoietin. (haematologica.org)
- This category includes polycythemia vera (PV), which is associated with acquired somatic mutations in the Janus kinase 2 gene ( JAK2 ), dominantly inherited primary familial and congenital polycythemia or erythrocytosis, caused by germline gain-of-function erythropoietin receptor ( EPOR ) mutations, 2 and erythrocytosis due to SH2B3 mutations. (haematologica.org)
- 4 3 Primary familial and congenital polycythemia or erythrocytosis predisposes patients to cardiovascular disorders, perhaps due to chronic augmented erythropoietin signaling in all tissues bearing EPOR. (haematologica.org)
- 6 5 1 Congenital secondary erythrocytosis can be caused by high oxygen affinity hemoglobin variants, inherited low 2,3-diphosphoglycerate leading to high hemoglobin oxygen affinity, congenital methemoglobinemia, and a recently described gain-of-function mutation of the gene encoding erythropoietin ( EPO ). (haematologica.org)
- By evaluating the changes in hemoglobin concentration and serum erythropoietin throughout the study, we were able to reveal the development of progressive anemia, resulting from diminished susceptibility to erythropoietin and unrelated to bone marrow fibrosis, in patients harboring CALR mutation. (bvsalud.org)
- Testing for the JAK2 V617F mutation and an erythropoietin (EPO) level helps differentiate secondary polycythemia from polycythemia vera. (medscape.com)
- Here we critically evaluate the role of elevated hematocrit as the principal determinant of thrombotic risk in polycythemia and erythrocytosis, defined by an expansion of red cell mass. (haematologica.org)
- Since red cell volume determination is no longer readily available, in clinical practice, polycythemia and erythrocytosis are defined by elevated hemoglobin and hematocrit. (haematologica.org)
- Thrombosis is common in Chuvash erythrocytosis and polycythemia vera. (haematologica.org)
- Although the increased thrombotic risk is assumed to be due to the elevated hematocrit and an associated increase in blood viscosity, thrombosis does not accompany most types of erythrocytosis. (haematologica.org)
- We review studies indicating that the occurrence of thrombosis in Chuvash erythrocytosis is independent of hematocrit, that the thrombotic risk is paradoxically increased by phlebotomy in Chuvash erythrocytosis, and that, when compared to chemotherapy, phlebotomy is associated with increased thrombotic risk in polycythemia vera. (haematologica.org)
- Inherited and environmental causes that lead to polycythemia and erythrocytosis are accompanied by diverse cellular changes that could directly affect thrombotic risk, irrespective of the elevated hematocrit. (haematologica.org)
- Defining these predisposing factors in polycythemia and erythrocytosis should then lead to rational therapies and facilitate development of targeted interventions. (haematologica.org)
- Decreased plasma volume with a normal red blood cell mass indicates a relative polycythemia or erythrocytosis, similar to the increased hemoglobin and hematocrit levels associated with severe dehydration. (medscape.com)
- The hemoglobin-oxygen dissociation curve may be determined in patients with a lifelong history (particularly a familial history) of erythrocytosis with normal oxygen saturation and normal levels of 2,3-diphosphoglycerate. (medscape.com)
- In the study we performed, we observed a significant, strong and negative correlation between the concentration of EPO, hemoglobin, and red blood cell count. (bvsalud.org)
- Additionally, there is a high oxygen concentration in the lungs and a low carbon dioxide concentration, which causes oxygen to move toward hemoglobin, increasing the amount of oxygen that is bound to hemoglobin. (medicalessays.com)
- Hemoglobin concentration (Hb) is used clinically to determine the presence of anemia , which is functionally defined as insufficient red blood cell (RBC) mass to adequately deliver oxygen to peripheral tissues. (medscape.com)
- Hemoglobin concentration (Hb) is usually reported as grams of hemoglobin per deciliter of blood (g/dL). (medscape.com)
- Automated blood cell counters usually measure hemoglobin concentration by a modified cyanmethemoglobin or an alternate lauryl sulphate method. (medscape.com)
- In the lungs, hemoglobin binds tightly to oxygen and releases carbon dioxide due to the slightly cooler body temperature and slightly less acidic pH. (medicalessays.com)
- The cellular environment causes hemoglobin to change its shape in a way that makes it more likely to bind to carbon dioxide (which is a waste product of active cells) and to release oxygen (which the cells need). (medicalessays.com)
- Measured arterial oxygen saturations of less than 92% may be associated with the development of a secondary polycythemia. (medscape.com)
- Formulas are available in which the measured arterial and venous oxygen saturations can be used to calculate the partial pressure of oxygen (PaO 2 ) at which hemoglobin is 50% saturated with oxygen. (medscape.com)
- This partial pressure value is a good estimate of the entire oxygen dissociation curve, because the shape of the dissociation curve varies only minimally, even with very high and very low oxygen affinity hemoglobins. (medscape.com)
- Hemoglobin is the main component of red blood cells and serves as the transporter for oxygen and carbon dioxide in the blood. (medscape.com)
- Hemoglobin Hemoglobin determinations will usually be performed by an automated cell counter from a tube of well-mixed EDTA-anticoagulated blood filled to a predetermined level. (medicalessays.com)
- The materials needed are: Lancets Alcohol prep pads Gauze pads Microhematocrit tubes (heparinized) Sealant ("Seal-Ease," "Crit-Seal," etc) Microhematocrit centrifuge Microhematocrit reader If venipuncture is required: tourniquet, syringe, tube containing anticoagulant (EDTA, citrate) For hematocrits obtained by fingerstick, wipe the fingertip pad of the fourth finger of the nondominant hand with the alcohol prep pad. (medicalessays.com)
- Causes of the second category include blood loss (hemorrhage), hemolysis of various etiologies (both intrinsic and extrinsic), and hemoglobin disorders (hemoglobinopathies and thalassemias). (medscape.com)
- An abdominal computed tomography (CT) scan or an intravenous pyelogram to investigate the kidneys and their function may be indicated in a minority of patients who may have a tumor or renal abnormalities that may be causing the polycythemia. (medscape.com)
- If JAK2 V617F mutation testing is negative but the EPO level is low, then testing for other mutations in exon 12 and 13 of JAK2 helps identify a small minority of patients with polycythemia vera. (medscape.com)
- All the other patients with wild-type JAK2 and a normal or elevated EPO level have secondary polycythemia. (medscape.com)
- Carboxyhemoglobin levels of greater than 8% in individuals who smoke or those who may have an occupational exposure to carbon monoxide may be associated with the development of polycythemia. (medscape.com)
- The pressing issue in these disorders is to define factors other than elevated hematocrit that determine thrombotic risk. (haematologica.org)
- The absorbance of the solution at 540 nm reflects the amount of hemoglobin present. (medscape.com)
- Demographic characteristics, delivery times of the baby and placenta, duration of uterine massage, amount of postpartum hemorrhage and postpartum hemoglobin values of both groups were recorded. (researchgate.net)
- For hematocrits obtained by venipuncture, draw a sample of blood into the tube containing anticoagulant and mix well. (medicalessays.com)
- Dip the hematocrit tube into the blood and allow the blood to rise to the desired two-thirds to three-quarters level. (medicalessays.com)
- In this assay, all forms of hemoglobins are converted to the colored protein cyanomethemoglobin and measured by a colorimeter. (medicalessays.com)
- All forms of hemoglobin are detected except sulfhemoglobin (SHb). (medscape.com)
- Plasma volume can also be calculated indirectly using total red blood cell mass and the hematocrit value. (medscape.com)
- Hb is commonly measured by the cyanhemoglobin (hemoglobin cyanide) method. (medscape.com)