HEMATOLOGY: RBC indices
10^(-12) g
1 pg
10^(-15) g or 1um^3
1fL is ?
RBC indices/Erythrocyte Indices
A valid tool for diagnosis of the specific type of Morphologic anemia.
Iron def. anemia, Vit. B12 def., Folic acid def.
Abnormally high results of RDW indicates
increased lipid, (+) for cold agglutinins, sample or mixing error
Falsely elevated MCHC
MCH = Hb (g/dl) x 10 / RBC/L or Hb(g/dl) / RBC (/L)
Formula of MCH
MCV = Hct(%)x10 / RBC(/L) or Hct(SI)/RBC(/L) x 100
Formula of MCV
optical density of HiCN
Hb is measured by?
Chronic Blood Loss
IDA is abnormally high due to?
MCV (Mean Corpuscular Volume)
Indicates average volume of RBC, expressed in Femtoliter/fl
macrocytic, hyperchromic (presence of central pallor increased)
MCH < 27 pg or elevated indicates?
microcytic, hypochromic RBC
MCH > 27 pg indicates?
hypochromia
MCHC < 33 g/dL indicates?
hyperchromia, spherocytosis
MCHC > 36 g/dL indicates? rarely 38 g/dL
below 22 g/dL
MCHC must not __ when hypochromia is present
above 38 g/dL
MCHC that is __ must not occur,
Microcytic, IDA, Parasitism
MCV is < 80fL indicates?
Macrocytic, Pernicious anemia, Vit. B12 def.
MCV is > 96fL indicates?
the mean height of the voltage pulses formed during Red Cell count
MCV is derived from?
Normocytic
MCV is normal
27-33 pg
Normal Range MCH
11.6 to 14.6%
Normal Value RDW
Falsely Low RBC
RBC is agglutinated (cold agglutinins may be present) causes?
Heterozygous thalassemia and Microcytic thalassemia
RDW is normal but MCV is low
not an indicator of iron def. in hemodialysis patients
RDW is sensitive but not?
80-96 fl
Reference range MCV
Thalassemia
Results are also normal within __ disorder
F, DIRECTLY PROPORTIONAL
T/F? MCH is indirectly proportional to the size of RC & conc. of Hb in the cell
Mean Corpuscular Hemoglobin Concentration
The expression of ave. conc. of Hb in the RBC, it gives the ratio of the weight of Hb to the vol. of RC expressed g/dL
Normochromic, Normocytic erythrocytes
The rule of three applies only to?
Spherocytosis
True elevated MCHC
To differentiate the morphologic type of anemia To function as a tool for quality of results
Uses of RBC indices
Rule of Three
a useful tool in ensuring quality assurance of RBC count, hemoglobin & hematocrit
incorrect calculation, or RBC is agglutinated (cold agglutinins may be present)
above 38g/dL occurs when?
Lipemic Plasma and Abnormal Hb (HbS & HbC)
below 22 g/dL occurs when?
Red Cell histogram
can be valuable in the diagnosis & treatment of patients
RDW (RBC Distribution Width)
generated by modern hematology analyzers estimates erythrocyte anisocytosis or size variation can be helpful adjunct in the classification and management disorders
Mean Corpuscular Hemoglobin
indicates the average weight of Hb in the blood cell. It is expressed in Picogram
normochromic
normal MCHC
3 x RBC = Hb 3 x Hb = HCT ± 3%
Basic Equations
