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Laboratory evaluation of erythrocyte. RBC Haemoglobin Packed cell volume. Quantitative description of erythropoiesis Anaemia, polycythaemia. Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia. MCV MCH MCHC. Reflects anisocytosis. RDW.
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Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume Quantitative description of erythropoiesis Anaemia, polycythaemia Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia MCV MCH MCHC Reflects anisocytosis RDW Reflects bone marrow erythropoietic activity hypoproliferative, hyperproliferative Reticulocyte Final assessment of the disorder abnormal RBC (fragments) Blood film
Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume Quantitative description of erythropoiesis Anaemia, polycythaemia Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia MCV MCH MCHC Reflects anisocytosis RDW Reflects bone marrow erythropoietic activity hypoproliferative, hyperproliferative Reticulocyte Final assessment of the disorder abnormal RBC (fragments) Blood film
MCV • HCT/RBC • RBC 5.000.000/microliter • Hematocrit 50% • The volume of RBC in 1 microliter • 0,0000001 microliter • 0,0001 nanoliter • 0,1 picoliter • 100 femtoliter [fL]
MCV (Mean Corpuscular Volume) • microcytic anemia • normocytic anemia • macrocytic anemia
MCHC • hypochromia • normochromia • hyperchromia
Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume Quantitative description of erythropoiesis Anaemia, polycythaemia Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia MCV MCH MCHC Reflects anisocytosis RDW Reflects bone marrow erythropoietic activity hypoproliferative, hyperproliferative Reticulocyte Final assessment of the disorder abnormal RBC (fragments) Blood film
MCV: 86 fl RDW: 10,5 % (Normal) MCV: 86 fl RDW: 19,0 % (Abnormal) RDW red cell populations with higher than normal RDW are termed heterogenous those with normal RDW are homogeneous anisocytosis is a general term reflecting increased variation in the size of red blood cells. The MCV will be within normal limits, but RDW will be increased.
Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume Quantitative description of erythropoiesis Anaemia, polycythaemia Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia MCV MCH MCHC Reflects anisocytosis RDW Reflects bone marrow erythropoietic activity hypoproliferative, hyperproliferative Reticulocyte Final assessment of the disorder abnormal RBC (fragments) Blood film
Reticulocyte Variation usually affects a continuum of red cell sizes, but occasionally two distinct red cell populations can be observed • sideroblastic anemia • red cell transfusion
Reticulocyte count • the number of reticulocytes is reported as a percentage of the total red cells – 0.5-2.5% • when the red cell count is low, the percentage of reticulocytes is inaccurately high, suggesting that more reticulocytes are present than there are in reality. For instance: • A normal person with an rbc count of 5,000,000 /microliter and an absolute reticulocyte count of 50,000 /microliter would have a relative retic count of 1.0%. • An anemic person with 2,000,000 rbc's/microliter and the same 50,000 retics/microliter would have an apparently "abnormal" relative retic count of 2.5 % and could be misdiagnosed
Reticulocyte index (RI) • A value of 45 is usually used as a normal hematocrit. • Hematocrit (%)......Retic survival (days)/maturation correction 36-45 1.0 26-35 1.5 16-25 2.0 15 and below 2.5 • So in a person whose reticulocyte count is 5%, hemoglobin 7.5 g/dL, hematocrit 25%, the RI would be: 5 x (25/45) /2 = 1.4 • RI 1.0 – 2.0 for a healthy individual. • RI < 2 with anemia indicates decreased production of reticulocytes and RBC • RI > 2 with anemia indicates hemolysis
Hypoproliferative Anemia • Microcytic • iron deficiency anemia • thalassemia (decreased globin chain synthesis) • sideroblastic anemia (decreased porphyrin synthesis) • anemia of chronic disease • Macrocytic • megaloblastic anemia (B12, folate deficiency) Hemolytic Anemia
Increased RBC turnover • RI • Serum unconjugated bilirubin • Haptoglobin concentration • Serum LDH
Hemolysis • Hereditary disorders include erythrocyte membrane and enzymatic defects and hemoglobin abnormalities. Some hereditary disorders include the following: • G-6-PD deficiency • Hereditary spherocytosis • Sickle cell anemia • Acquired hemolytic conditions can be due to immune disorders, toxic chemicals and drugs, antiviral agents (eg, ribavirin), physical damage, and infections. They can include the following: • autoimmune hemolytic anemia (AIHA) • disseminated intravascular coagulation (DIC) • hemolytic uremic syndrome (HUS) • thrombotic thrombocytopenic purpura (TTP) • defective prosthetic cardiac valves • Autoimmune hemolytic anemia and hereditary spherocytosis are classified as examples of extravascular hemolysis because the RBCs are destroyed in the spleen and other reticuloendothelial organs (RES). • Intravascular hemolysis occurs in hemolytic anemia due to prosthetic cardiac valves, G-6-PD deficiency, thrombotic thrombocytopenic purpura, disseminated intravascular coagulation • Fragmented erythrocytes (schistocytes)
Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume Quantitative description of erythropoiesis Anaemia, polycythaemia Qualitative description of erythropoiesis Micro-, normo-, nacrocytosis; Hypo-, normo-, hyperchromia MCV MCH MCHC Reflects anisocytosis RDW Reflects bone marrow erythropoietic activity hypoproliferative, hyperproliferative Reticulocyte Final assessment of the disorder abnormal RBC (fragments) Blood film
Variation in shape • poikilocytosis • poikilocyte is pear-shaped and so also called a teardrop cell • poikilocytosis can refer to an increase in abnormal red blood cells of any shape where they make up 10% or more of the total population.
Megaloblastic anemias • macrocytic anemia with thrombocytopenia and a decreased reticulocyte count • MCV can range from 100-150 fL or greater • hypersegmented neutrophils can be observed on the peripheral smear • Hypersegmented neutrophils contain 5 or more lobes, while normal neutrophils contain 3-4 lobes • macrocytes are oval and have been called macroovalocytes. • In persons with severe anemia, macrocytes with nuclear remnants and erythrocytes with megaloblastic nuclei can be present in the peripheral blood • Macrocytes can be found in the peripheral blood in patients with liver disease or hemolytic anemia and usually do not have oval features • increased LDH and indirect bilirubin levels along with a decreased reticulocyte count suggest ineffective hemopoiesis in which intramedullary hemolysis is occurring. • LDH level is an excellent indication of response to or failure of therapy