differential staining

Differential staining is a staining process which uses more than one chemical stain.{{cite book |last1=Krueger |first1=Woodrow B. |title=Laboratory procedures for general microbiology |date=1986 |publisher=Kendall/Hunt Pub. Co |isbn=9780840338044 |page=25 |url=https://archive.org/details/laboratoryproced0000krue/page/24/mode/2up?q=%22Differential+staining%22 |access-date=21 December 2021}} Using multiple stains can better differentiate between different microorganisms or structures/cellular components of a single organism.

Differential staining is used to detect abnormalities in the proportion of different white blood cells in the blood. The process or results are called a WBC differential. This test is useful because many diseases alter the proportion of certain white blood cells. By analyzing these differences in combination with a clinical exam and other lab tests, medical professionals can diagnose disease.

One commonly recognizable use of differential staining is the Gram stain. Gram staining uses two dyes: Crystal violet and Fuchsin or Safranin (the counterstain) to differentiate between Gram-positive bacteria (large Peptidoglycan layer on outer surface of cell) and Gram-negative bacteria.

Acid-fast stains are also differential stains.