Hema Lab

What is the normal range for leukocyte count in x10^9/L?

3.6-10.6 x 10^9/L

What is the preferred specimen for WBC counting?

EDTA blood sample.

What happens to WBC morphology within 30 minutes of using EDTA?

Nuclei of neutrophils swell, loss of chromatin, cytoplasmic vacuoles appear in monocytes and neutrophils.

What is the purpose of the hemacytometer in manual WBC counting?

To check the validity of electronic methods and counts.

How is the Levy chamber structured for counting WBC?

It has two raised surfaces with a 3mm x 3mm counting area and an H-shaped moat.

What is the dilution factor typically used for WBC count with a Thoma pipette?

1:20.

What is the color of the bead used in a WBC Thoma pipette?

White.

What type of fluid is used for diluting in the eosinophil counting method?

Phloxine diluting fluid.

What is the typical concentration of 1% HCl solution used in WBC counting?

1 mL Concentrated HCl + 100 mL distilled H2O.

What counting method involves classifying leukocytes according to maturity?

Schilling's hemogram.

What percentage of WBCs should be counted for accuracy when the count exceeds 40 x10^9/L?

At least 200 cells.

What formula is used to calculate the absolute WBC count?

Absolute count = relative count x Total WBC count.

What is called when there is an increase in young forms of WBCs?

Shift to the Left.

What does a degenerative shift to the left indicate?

Increase in the number of young forms with normal or decreased WBC count.

What types of errors can occur in manual differential WBC count?

Sampling error, inadequate mixing, poor staining, cell ID errors.

What causes spurious decreases in automated WBC counts?

Clotting of specimen, smudge cells, and unlysed RBCs.

What is the reference range for neutrophils in percentage and absolute count?

50-70% and 1.7-7.5 X 10^3/uL respectively.

What is the significance of checking the sum of the percentages in WBC counts?

It should equal 100%.

What does the result '3% eosinophils' signify in a WBC count?

The relative frequency of eosinophils in the sample.

What error might occur if the pipet is faulty during WBC counting?

It could lead to an inaccurate count.

What is a leukocyte?

A white blood cell that helps the body fight infections.

What is the function of neutrophils?

Neutrophils are the first responders to sites of infection and help to engulf pathogens.

What are lymphocytes responsible for?

Lymphocytes are crucial for the adaptive immune response and include T cells and B cells.

What is the role of platelets in blood?

Platelets are involved in blood clotting to prevent bleeding.

What is the lifespan of a red blood cell?

Red blood cells typically live for about 120 days in the bloodstream.

What does the term 'anemia' refer to?

Anemia is a condition characterized by a deficiency of red blood cells or hemoglobin in the blood.

What is the role of plasma in blood?

Plasma is the liquid component of blood that carries cells, nutrients, hormones, and waste products.

What is the significance of a complete blood count (CBC)?

A CBC provides information about the different components of blood and helps diagnose various conditions.

What does the term 'hematocrit' measure?

Hematocrit measures the percentage of blood volume occupied by red blood cells.

What can a high white blood cell count indicate?

A high white blood cell count may indicate infection, inflammation, stress, or more serious conditions like leukemia.