An undiluted CSF sample is loaded on a Neubauer hemocytometer. Side 1 yields 100 WBCs and Side 2 yields 55 WBCs. What should the MLS do?

An undiluted CSF sample is loaded on a Neubauer hemocytometer. Side 1 yields 100 WBCs and Side 2 yields 55 WBCs. What should the MLS do?

• A. Report the average WBC/µL from side 1 and side 2
• B. Report the difference in WBC/µL from side 1 and side 2
• C. Report the sum of WBCs/µL from side 1 and side 2
• D. Clean and reload the hemocytometer

Answer: (D)

Uniform cell distribution in a Neubauer chamber is required for an accurate WBC count. When counting CSF in the chamber, counts from corresponding areas on both sides should be similar. A large discrepancy, like one side showing 100 cells and the other 55, indicates something went wrong with loading or distribution—air bubbles, debris, or an imperfect coverslip contact can cause uneven spreading of cells. The correct course is to clean the chamber and reload the sample, then re-count to obtain a reliable value. Averaging or summing the two counts would not address the underlying distribution issue and could misrepresent the true cell concentration. Reloading restores even distribution and yields a trustworthy WBC/µL calculation.

Uniform cell distribution in a Neubauer chamber is required for an accurate WBC count. When counting CSF in the chamber, counts from corresponding areas on both sides should be similar. A large discrepancy, like one side showing 100 cells and the other 55, indicates something went wrong with loading or distribution—air bubbles, debris, or an imperfect coverslip contact can cause uneven spreading of cells.

The correct course is to clean the chamber and reload the sample, then re-count to obtain a reliable value. Averaging or summing the two counts would not address the underlying distribution issue and could misrepresent the true cell concentration. Reloading restores even distribution and yields a trustworthy WBC/µL calculation.