CSMLS Important
equations, Safety &
Quality questions and
answers well
illustrated.
Corrected reticulocyte count CORRECT ANSWER.% retics x HCT / 45
Corrected WBC count CORRECT ANSWER.WBC x 100 / NRBCs + 100
Manual RBC or WBC count on a hemacytometer CORRECT ANSWER.average x
dilution factor / 0.
*four squares counted
Mean Cell Volume (MCV) CORRECT ANSWER.HCT / RBC
count 80-100 fL
Mean Cell Hemoglobin (MCH) CORRECT ANSWER.HGB / RBC
count 26-34 pg
Mean Corpuscular Hemoglobin Concentration (MCHC) CORRECT
ANSWER.HGB / HCT 320-360 g/L
Absolute WBC count CORRECT ANSWER.total WBC x % specific cells
, What is the rule of 3? CORRECT ANSWER.RBC x 3 = HGB x 3 = HCT
Reticulocyte Production Index (RPI) CORRECT ANSWER.(pt HCT/mean HCT) (retic
count/maturation time)
Adjusted citrate calculation CORRECT ANSWER.(1.85 x 10^3) (100-pt HCT)
(volume)
What is the principle of electrical impedance (direct current)? CORRECT
ANSWER.Cells do not conduct electricity but are suspended in fluid that does.
As they pass between 2 electrodes, the cells impede the current and
generate a pulse
What pH is maintained in a Wright/Wright-Giemsa stain? CORRECT ANSWER.6.4-6.8
What is VCS technology? CORRECT ANSWER.Provides 5 part WBC differential
-Volume: low frequency "Coulter principle" to measure & size cells
-Conductivity: CW is conductor to high frequency current, allowing it to pass
through cell membrane & measure nuclear/granular constituents and chemical
composition
-Light Scatter: flow cytometry and laser measure granularity, nuclear
appearance & cell surface characteristics (forward-size; side-internal)
What is Hydrodynamic focusing? CORRECT ANSWER.Used alongside direct
current detection. Cuts down on coincidence counting by counting RBC/PLT
in a dedicated channel
What is the principle of Fluorescent optical platelets (PLT-O)? CORRECT
ANSWER.Uses fluorescent flow cytometry via reticulocyte channel to include
PLTs into the count and exclude RBC fragments
-Giant PLT: higher fluorescent intensity
-RBC frag: lower fluorescent intensity
How are NRBCs and WBCs differentiated on automated analyzers? CORRECT
ANSWER.NRBC channel uses lysing agent and fluorescent dye. WBCs bind a
larger amount of dye than NRBCs and demonstrate a high intensity
fluorescence
How long can EDTA samples for Hematology be stored prior to testing?
CORRECT ANSWER.24 hours at RT and in fridge for 48 hours
Albumin/Globulin ratio CORRECT ANSWER.Alb/ TP-Alb
Creatinine clearance CORRECT ANSWER.U/P x V(mL)/T(sec) x 1.73/A =
mL/s/1.73m2
Anion gap CORRECT ANSWER.Na - (Cl +
HCO3) 7-16 mmol/L
Osmolal Gap CORRECT ANSWER.Measured osmo - calculated osmo
equations, Safety &
Quality questions and
answers well
illustrated.
Corrected reticulocyte count CORRECT ANSWER.% retics x HCT / 45
Corrected WBC count CORRECT ANSWER.WBC x 100 / NRBCs + 100
Manual RBC or WBC count on a hemacytometer CORRECT ANSWER.average x
dilution factor / 0.
*four squares counted
Mean Cell Volume (MCV) CORRECT ANSWER.HCT / RBC
count 80-100 fL
Mean Cell Hemoglobin (MCH) CORRECT ANSWER.HGB / RBC
count 26-34 pg
Mean Corpuscular Hemoglobin Concentration (MCHC) CORRECT
ANSWER.HGB / HCT 320-360 g/L
Absolute WBC count CORRECT ANSWER.total WBC x % specific cells
, What is the rule of 3? CORRECT ANSWER.RBC x 3 = HGB x 3 = HCT
Reticulocyte Production Index (RPI) CORRECT ANSWER.(pt HCT/mean HCT) (retic
count/maturation time)
Adjusted citrate calculation CORRECT ANSWER.(1.85 x 10^3) (100-pt HCT)
(volume)
What is the principle of electrical impedance (direct current)? CORRECT
ANSWER.Cells do not conduct electricity but are suspended in fluid that does.
As they pass between 2 electrodes, the cells impede the current and
generate a pulse
What pH is maintained in a Wright/Wright-Giemsa stain? CORRECT ANSWER.6.4-6.8
What is VCS technology? CORRECT ANSWER.Provides 5 part WBC differential
-Volume: low frequency "Coulter principle" to measure & size cells
-Conductivity: CW is conductor to high frequency current, allowing it to pass
through cell membrane & measure nuclear/granular constituents and chemical
composition
-Light Scatter: flow cytometry and laser measure granularity, nuclear
appearance & cell surface characteristics (forward-size; side-internal)
What is Hydrodynamic focusing? CORRECT ANSWER.Used alongside direct
current detection. Cuts down on coincidence counting by counting RBC/PLT
in a dedicated channel
What is the principle of Fluorescent optical platelets (PLT-O)? CORRECT
ANSWER.Uses fluorescent flow cytometry via reticulocyte channel to include
PLTs into the count and exclude RBC fragments
-Giant PLT: higher fluorescent intensity
-RBC frag: lower fluorescent intensity
How are NRBCs and WBCs differentiated on automated analyzers? CORRECT
ANSWER.NRBC channel uses lysing agent and fluorescent dye. WBCs bind a
larger amount of dye than NRBCs and demonstrate a high intensity
fluorescence
How long can EDTA samples for Hematology be stored prior to testing?
CORRECT ANSWER.24 hours at RT and in fridge for 48 hours
Albumin/Globulin ratio CORRECT ANSWER.Alb/ TP-Alb
Creatinine clearance CORRECT ANSWER.U/P x V(mL)/T(sec) x 1.73/A =
mL/s/1.73m2
Anion gap CORRECT ANSWER.Na - (Cl +
HCO3) 7-16 mmol/L
Osmolal Gap CORRECT ANSWER.Measured osmo - calculated osmo
