Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume MCV MCH MCHC RDW...
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Transcript of Laboratory evaluation of erythrocyte RBC Haemoglobin Packed cell volume MCV MCH MCHC RDW...
Laboratory evaluation of erythrocyte
RBCHaemoglobin
Packed cell volume
MCVMCH
MCHC
RDW
Reticulocyte
Blood film
Quantitative description of erythropoiesisAnaemia, polycythaemia
Qualitative description of erythropoiesisMicro-, normo-, nacrocytosis;Hypo-, normo-, hyperchromia
Reflects anisocytosis
Reflects bone marrow erythropoietic activityhypoproliferative, hyperproliferative
Final assessment of the disorderabnormal RBC (fragments)
Laboratory evaluation of erythrocyte
RBCHaemoglobin
Packed cell volume
MCVMCH
MCHC
RDW
Reticulocyte
Blood film
Quantitative description of erythropoiesisAnaemia, polycythaemia
Qualitative description of erythropoiesisMicro-, normo-, nacrocytosis;Hypo-, normo-, hyperchromia
Reflects anisocytosis
Reflects bone marrow erythropoietic activityhypoproliferative, hyperproliferative
Final assessment of the disorderabnormal RBC (fragments)
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
RBCHaemoglobin
Packed cell volume
MCVMCH
MCHC
RDW
Reticulocyte
Blood film
Quantitative description of erythropoiesisAnaemia, polycythaemia
Qualitative description of erythropoiesisMicro-, normo-, nacrocytosis;Hypo-, normo-, hyperchromia
Reflects anisocytosis
Reflects bone marrow erythropoietic activityhypoproliferative, hyperproliferative
Final assessment of the disorderabnormal RBC (fragments)
RDWMCV: 86 flRDW: 10,5 % (Normal)
MCV: 86 flRDW: 19,0 % (Abnormal)
red cell populations with higher than normal RDW are termed heterogenousthose with normal RDW are homogeneousanisocytosis 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
RBCHaemoglobin
Packed cell volume
MCVMCH
MCHC
RDW
Reticulocyte
Blood film
Quantitative description of erythropoiesisAnaemia, polycythaemia
Qualitative description of erythropoiesisMicro-, normo-, nacrocytosis;Hypo-, normo-, hyperchromia
Reflects anisocytosis
Reflects bone marrow erythropoietic activityhypoproliferative, hyperproliferative
Final assessment of the disorderabnormal RBC (fragments)
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
RBCHaemoglobin
Packed cell volume
MCVMCH
MCHC
RDW
Reticulocyte
Blood film
Quantitative description of erythropoiesisAnaemia, polycythaemia
Qualitative description of erythropoiesisMicro-, normo-, nacrocytosis;Hypo-, normo-, hyperchromia
Reflects anisocytosis
Reflects bone marrow erythropoietic activityhypoproliferative, hyperproliferative
Final assessment of the disorderabnormal RBC (fragments)
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.
IDA
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