Red Cell Indices Flashcards
In 1929, Wintrobe introduced mathematical way of determining the average size, hemoglobin content, and concentration of red blood cells.
These are the erythrocyte indices, or….
RBC indices
RBC indices
These parameters are calculated from (3). To date, the RBC indices have been useful in the morphologic characterization of anemia.
red cell count, hemoglobin, and hematocrit
In addition, it also serves as a quality control check of hematology analyzers.
RBC indices
The RBC Indices are:
- Mean Cell Volume (MCV)
- Mean Cell Hemogicbin (MCH)
- Mean Cell Hemoglobin Concentration (MCHC)
Also known as mean corpuscular volume, the MCV
reflects the average volume of a red cell, which is also reflective of its average size.
Mean cell volume
It is expressed in femtoliters (fL) or 10-15L.
Mean cell volume
MCV
reference
80-100 fL
MCH
cell ref
26-32 pg
MCHC
Reference range
32-36 g/dL
Related to the size RBC
Mean Cel Volume (MCV)
- Average volume of RBC in a given sample
Mean Cell Volume (MCV)
• Related to the color of RBCs when examined under the microscope
Mean Cell Hemoglobin (MCH)
Mean Cell Hemoglobin Concentration (MCHC)
• Average content (weight) of hemoglobig in a single RBC
Mean Cell Hemoglobin (MCH)
Average conc of hemoglobin in a unit volume of RBCs in a sample
Mean cell hemoglobin concentration
is helpful in classifying anemias based on size.
MCV
MCV: Causes of spurious increase
Autoagglutination
High WEC (>50,000/uL)
Hyperglycemia
Reduced red cell deformability
MCV: Causes of spurious decrease
Cryoglobulin
Cryofibrinogen
Giant platelets
Hemolysis (in vitro)
Microcytic red cell
Swollen red cell
, is a measure of the content (weight) of hemoglobin per red cell.
MEAN CELL HEMOGLOBIN (MCH)
It is directly proportional to the amount of hemoglobin and the size of the REC. it is expressed in picograms, or 10-12 pg
MCH
However, generally,____ is not considered in the classification of anemias.
MCH
Clinica/ Significance
In anemias due to impaired hemoglobin production, such as thalassemia and iron deficiency anemia, the hemoglobin mass per RBC decreases.
Mean Cell Hemoglobin
Sources of Errors in MCH Measurement
Causes of spurious increase
Hyperlipidemia
Plasma Turbidity
It is expressed as grams per deciliter (formerly expressed as percentage).
MEAN CELL HEMOGLOBIN CONCENTRATION (MCHC)
It can also be defined as the ratio of the weight of the hemoglobin to the volume of red cells.
MEAN CELL HEMOGLOBIN CONCENTRATION (MCHC)
Also known as …, it is the average concentration of hemoglobin in a given volume of packed red cells.
MEAN CELL HEMOGLOBIN CONCENTRATION (MCHC)
MCHC: Causes of spurious increase
Auto agglutination
Clotting
Hemolysis (in vitro/vivo)
Spuriously high Hb or low/ HCT
MCHC: Causes of spurious decrease
High WBC (>50, 000/uL)
Spuriously low Hb
Spuriously high HCT
The________ is a red cell numerical parameter that reflects the heterogeneity of red cell volume (or size) in a given sample.
red cell distribution width
It has been suggested that_____ can be used as an early indicator for classifying anemia, as it tends to deviate from normal levels earlier in nutritional deficiency anemias compared to other red cell parameters, particularly in cases of iron deficiency anemia.
MCHC
The______ is a valuable parameter for characterizing microcytic anemias.
It plays a crucial role in distinguishing between different types of anemias, especially when trying to differentiate uncomplicated iron deficiency anemia and uncomplicated heterozygous thalassemia.
RDW (Red Cell Distribution Width)
• Autoagglutination
Increase MCV
• Hyperosmolar State
Increase MCV
• Old Specimen
Increase MCV
• Autoagglutination
• False increase of MCH and
MCHC
• Turbid Plasma
• False increase of MCH and
MCHC
Microcytic
> 80 fL
Thalassemia
Anemia of chronic disease
Iron deficiency anemia
Lead poisoning
Sideroblastic anemia
Macrocytic
> 100 fL
Megaloblastic
- vitB12 deficiency
- folate deficiency
Non-Megaloblastic
- aplastic anemia
- chromic liver disease
- alcoholism
