Why are leukocytes found in blood smears?

The blood smear allows for the evaluation of these cells: White blood cells (WBCs, leukocytes) — help fight infections or participate in immune responses. Red blood cells (RBCs, erythrocytes) — carry oxygen to tissues. Platelets (thrombocytes) — small cell fragments that are vital to proper blood clotting.

What is the advantage of a blood smear compared to a complete blood count?

The white blood cell count on a blood smear gives important information about the number of the different types of blood cells as well as other findings. When a particular type of white blood cells is increased, it can give important clues about underlying problems.

How are leukocytes detected in a blood smear?

Note – it is easy to confuse the different leucocytes in blood smears. To identify them, you need to look for the shape of the nucleus, and compare their size, relative to that of a red blood cell.

What does a blood smear test tell you?

A blood smear is a blood test used to look for abnormalities in blood cells. The three main blood cells that the test focuses on are: red cells, which carry oxygen throughout your body. white cells, which help your body fight infections and other inflammatory diseases.

Why is a good blood smear necessary for accurate counts?

From the clinical standpoint, blood smear examination serves 3 important objectives. First, it serves as a quality control tool in verifying the results generated by the automated analyzers. Second, it allows for identification of abnormal/immature/atypical cells, if present.

Why would one perform a differential leukocyte count?

A white blood cell (WBC) count measures the number of white blood cells in your blood, and a WBC differential determines the percentage of each type of white blood cell present in your blood. A differential can also detect immature white blood cells and abnormalities, both of which are signs of potential issues.

What’s the advantage of a blood smear compared to a complete blood count quizlet?

What’s the advantage of a blood smear compared to a CBC? Blood smears focus on RBC, WBC, platelets, and in some cases can help identify blood parasites. Viruses cannot be identified with this technique due to their small size.

How can you tell the difference between monocytes and lymphocytes?

Monocyte and Lymphocytes – Difference

Why are white blood cells in a stained blood smear usually counted at low power under a microscope?

This area of the smear is usually scanned at low power to identify low numbers of potentially diagnostic cells (e.g. blasts in a leukemia), infectious agents (e.g. trypanosomes, microfilaria), and certain RBC changes (hypochromasia, agglutinates).

Which area of the blood smear is used for the differential leukocyte count?

Scan the smear at low magnification (10x objective). Locate the optimal area for examination at higher magnification to perform a differential leukocyte count and examine morphologic features of blood cells. This optimal area is the monolayer (usually; see above), where cells are uniformly distributed and well spread.

Why is peripheral blood smear evaluation important?

However, microscopic evaluation of peripheral blood smears affords clinicians additional data that may be used to guide diagnosis and treatment. Examining the monolayer of a well-prepared and properly stained blood smear allows veterinary technicians to assess erythrocyte (RBC), leukocyte (WBC) and platelet morphology.

What are the important considerations in the preparation of a perfect peripheral blood smear?

It takes considerable practice to consistently make perfect blood smears. The handmade wedge or thin slide is the most commonly prepared blood film. Three factors may be altered slightly to produce a perfect blood smear: speed, angle and drop size.

Why are leukocytes smaller in the thick part of a smear?

The thick area of a smear dries too slowly for leukocytes to spread out. The white cells here are shrunken and appear much smaller than in the quickly dried areas – individual leukocytes can be difficult to identify in this area and red blood cell changes are hard to appreciate.

What is the normal distribution of erythrocytes on a smear?

In preparations from normal patients, the thin section of the smear occupies approximately 1/3 of the total area and, within that area; erythrocytes are distributed in a monolayer.

What does a blood smear test look for?

For a blood smear test, a laboratory professional examines the slide under a microscope and looks at the size, shape, and number of different types of blood cells. These include: Many blood tests use computers to analyze results. For a blood smear, the lab professional looks for blood cell problems that may not be seen on a computer analysis.

What are the limitations of a blood smear?

There are a few limitations to a blood smear. If a person has received a blood transfusion, the smear will include a combination of native and donated blood cells. 2  There are several potential ways in which error can enter into a blood smear.