Question

Which of the following diluents should be used when an RBC count is requested?

• A. Dilute acetic acid
• B. Hypotonic saline
• C. Isotonic saline
• D. Turk’s solution

Hint:

Always use isotonic saline for RBC counts to preserve cell structure and ensure accurate results.

Answer 1

The Correct Option is C

Isotonic saline (0.85% NaCl) is used as a diluent for RBC counts because it maintains the integrity of the red blood cells, preventing hemolysis. Other diluents, such as dilute acetic acid or Turk’s solution, are used for WBC counts as they lyse red blood cells to better visualize white blood cells.