What is the significance of a positive acid fast smear?

What is the significance of a positive acid fast smear?

A positive result means that bacteria were found and that you may have an infection. The smear is treated with a special acid-fast stain that can provide a preliminary test result in 24 hours. At the same time, another sample of sputum is also tested as a culture.

Why do we use acid alcohol in acid fast staining?

Acid alcohol has the ability to completely decolorize all non-acid-fast organisms, thus only leaving behind red-colored acid-fast organisms, like M. Tuberculosis. The slides are then stained a second time with methylene blue that serves as a counterstain.

Why is an acid fast stain used Why is it necessary to use steam in this process what type of stain is it?

Acid-fast stain is a differential stain used to identify acid-fast organisms such as members of the genus Mycobacterium. Steam helps to loosen up the waxy layer and promotes entry of the primary stain inside the cell. …

What disease is caused by acid fast bacteria?

Acid-fast bacillus (AFB) is a type of bacteria that causes tuberculosis and certain other infections. Tuberculosis, commonly known as TB, is a serious bacterial infection that mainly affects the lungs.

Is an example of acid fast bacteria?

Common acid-fast bacteria of medical importance include Mycobacterium tuberculosis, Mycobacterium leprae,Mycobacterium avium-intracellulare complex, and Nocardia species.

Is leprosy caused by an acid fast bacteria?

Leprosy (Hansen’s Disease) Mycobacterium leprae is an obligate intracellular pathogen, first identified in the nodules of lepromatous leprosy patients by Armauer Hansen in 1873. It is a rod-shaped, Gram-positive organism that is acid-fast when stained by the Ziehl–Nielsen or the better Fite methods.

Why is methylene blue used in acid fast staining?

The non-acid fast organism lack the lipoidal material in their cell wall due to which they are easily decolorized, leaving the cells colorless. Then the smear is stained with counterstain, methylene blue.

What infections are Gram negative?

Gram-negative bacterial infections include the following:

  • Brucellosis.
  • Campylobacter infections.
  • Cat-scratch disease.
  • Cholera.
  • Escherichia coli (E. coli) infections.
  • Haemophilus influenzae infections.
  • Klebsiella infections.
  • Legionnaires’ disease.