The Ziehl–Neelsen stain, also known as the acid-fast stain. The main aim of this staining is to differentiate bacteria into acid fast group and non-acid fast groups.
The acid-fast stain is a differential stain used to identify acid-fast organisms such as members of the genus Mycobacterium . Acid-fast organisms are characterized by wax-like, nearly impermeable cell walls; they contain mycolic acid and large amounts of fatty acids, waxes, and complex lipids.
A positive test result from the acid-fast stain confirms the patient has TB.