AIM: To provide information on the different white blood cells (neutrophils, basophils, eosinophils, lymphocytes, monocytes) present in the cerebrospinal fluid (CSF) specimen.
MATERIAL/APPARATUS: CSF specimen, methylene blue stain, microscope, glass slide, water, Bunsen burner, inoculating loop, immersion oil.
METHOD/PROCEDURE FOR DIFFERENTIAL COUNT OF CSF SAMPLE
- Place a drop of the CSF specimen on a clean glass slide.
- Spread the sample on the slide using a sterilized inoculating loop and allow to dry.
- Heat-fix the smear on the glass slide.
- Flood the slide with methylene blue stain.
- Allow for 5 minutes. Then wash off the methylene blue stain with water.
- Allow the slide to dry completely.
- Add a drop of immersion oil on the slide.
- View the slide under the microscope using the ×100/oil immersion objective lens.
- Systematically examine the slide and count the different white cells seen in each field.
REPORTING OF THE RESULT: Report the number of the different white blood cells seen under the microscope.
NOTE: Differential white cell count can be performed using 3 types of stains:
- Methylene blue stain.
- Giemsa stain.
- Leishma stain.
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