DIFFERENTIAL COUNT FOR CSF

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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