The unique ability of mycobacteria to resist decolorization by acid-alcohol is why they are termed acid-fast. It involves the application of a primary stain (basic fuchsin), a decolorizer (acid-alcohol), and a counterstain (methylene blue).
Why is the kinyoun method called the cold method?
The Kinyoun staining procedure is often referred to as cold carbolfuchsin because no heat is applied during the staining process unlike the Ziehl- Neelsen procedure. The primary stain for the Kinyoun procedure is the aniline dye, basic fuchsin, that stains all the cells present red.
When is Kinyoun acid fast stain used?
Acid fast stains are used to differentiate acid fast organisms such mycobacteria. Acid fast bacteria have a high content of mycolic acids in their cell walls. Acid fast bacteria will be red, while nonacid fast bacteria will stain blue/green with the counterstain with the Kinyoun stain.
Why are mycobacteria referred to as acid-fast?
The acid-fastness of Mycobacteria is due to the high mycolic acid content of their cell walls, which is responsible for the staining pattern of poor absorption followed by high retention.Why ZN staining is called acid-fast?
Mycobacterium and many Nocardia species are called acid-fast because during an acid-fast staining procedure they retain the primary dye carbol fuchsin despite decolorization with the powerful solvent acid-alcohol. Nearly all other genera of bacteria are nonacid-fast.
What is the mordant in kinyoun acid-fast staining?
Kinyoun, is a procedure used to stain acid-fast species of the bacterial genera Mycobacterium and Nocardia and the apicomplexan genus Cryptosporidium. … In the Ziehl–Neelsen stain, heat acts as a physical mordant while phenol (carbol of carbol fuschin) acts as the chemical mordant.
What is the primary stain in the kinyoun acid fast stain quizlet?
What is the primary stain in acid fast stain? The primary stain in the Ziel-Neelsen method is carbol fuchsin, and basic fuchsin in the Kinyoun method.
How do mycobacteria appear on acid-fast staining?
Acid fast stains are used to differentiate acid fast organisms such mycobacteria. Acid fast bacteria have a high content of mycolic acids in their cell walls. Acid fast bacteria will be red, while nonacid fast bacteria will stain blue/green with the counterstain with the Kinyoun stain.What is the procedure for acid-fast staining?
- Air dry and heat fix a thin film of microorganisms. …
- Flood the slide with Carbolfuchsin. …
- Flood slide with Acid Alcohol for 30 seconds. …
- Counterstain by flooding the slide with Methylene Blue for 30 seconds. …
- Dry the slide by putting it between the pages of a book of Bibulous paper.
Mycolic acid is the wax-like lipid present in the walls of acid-fast cells. This material makes cells resistant to staining, but also makes them resistant to being decolorized once they have been successfully stained.
Article first time published onWhat is cold staining?
The cold staining method is simple, because it eliminates heatingof stain. For direct smear, the correlations of cold staining procedure with conventional ZN method was 93% and for post concentration smear it was 100%. KEY WORDS: Acid fast bacilli, Mycobacterial cold staining.
How is kinyoun method being performed?
Procedure of Kinyoun-Cold Method Cover the smear with carbolfuchsin for 3 to 5 minutes at room temperature. Gently rinse the slide with water. Run 1% sulfuric acid decolorizer over the slide for approximately 3 minutes. Rinse the slide with water and decolorize again for 1 to 2 minutes until the solution runs clear.
What is the difference of kinyoun over the Ziehl-neelsen method?
The fundamental difference between the two carbolfuchsin-based methods is whether heat is used during the primary staining process. The Ziehl-Neelsen method uses heat to infuse the carbolfuchsin into the acid-fast cells, whereas the Kinyoun method does not use heat.
What does the term acid-fast mean?
Acid fastness is a physical property that gives a bacterium the ability to resist decolorization by acids during staining procedures. This means that once the bacterium is stained, it cannot be decolorized using acids routinely used in the process.
What is acid fast stain quizlet?
Acid Fast Stain. *A differential stain which distinguishes bacteria based on cell wall properties. *Gram positive microorganisms that are resistant to gram stain, acid fast allows us to see this bacteria. mycolic acid. a waxy substance in cell walls of acid fast bacteria.
When is acid-fast staining used quizlet?
What is the purpose of an Acid-Fast stain? It is a differential stain used to detect cells capable of retaining a primary stain when treated with an acid alcohol.
What are the stains used in acid fast staining enumerate and describe?
Principle of Acid-Fast Stain 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 is the primary stain in the spore stain?
Because of their tough protein coats made of keratin, spores are highly resistant to normal staining procedures. The primary stain in the endospore stain procedure, malachite green, is driven into the cells with heat.
Which of the following is the defining characteristic of acid-fast bacteria?
Acid-fast bacteria are gram-positive, but in addition to peptidoglycan, the outer membrane or envelope of the acid-fast cell wall of contains large amounts of glycolipids, especially mycolic acids that in the genus Mycobacterium, make up approximately 60% of the acid-fast cell wall (Figure 2.3C. 2).
What is acid fast staining in microbiology?
The acid-fast stain is a laboratory test that determines if a sample of tissue, blood, or other body substance is infected with the bacteria that causes tuberculosis (TB) and other illnesses.
What is the mordant used in the K technique?
Salts of chromium, aluminum, copper, iron, tin, and cobalt are commonly used as mordants. Since the mordant affects the electron distribution and density within the dye, the color of the dyed fabric tends to change.
What is the secondary stain in both the kinyoun and Ziehl Neelsen acid fast stain methods?
Differential staining – glacial acetic acid used, no heat applied, secondary stain is Loeffler’s methylene blue. Kinyoun modification (or cold Ziehl–Neelsen technique) is also available.
Why is the acid fast stain clinically useful quizlet?
Why is the acid-fast stain clinically important? The acid-fast stain is used in the diagnosis of TB (Mycobacterium tuberculosis) a significant health concern worldwide. Additionally, this stain is useful in the diagnosis of diseases caused by other members of the genus Mycobacterium (M. avium and M.
Why are acid fast bacteria slow growers quizlet?
-the complex fatty acids and other lipids outside the peptidoglycan layer make the mycobacteria resist acid alcohol treatment. – and they also impede the entry of chemicals, causing slow growth and also resistance to chemical agents and lysosomal components of phagocytes.
Which organisms are acid fast quizlet?
- Genus Nocardia.
- Mycobacterium tuberculosis.
- Mycobacterium leprae.
What is stained by the counterstain in the acid fast stain procedure quizlet?
What is the function of the counterstain in the acid-fast staining procedure? The counterstain stains non-acid-fast bacteria blue if using Methylene Blue or green if using Brilliant Green. You just studied 7 terms!
What is cold acid fast staining?
The Kinyoun method or Kinyoun stain (cold method), developed by Joseph J. Kinyoun, is a procedure used to stain acid-fast species of the bacterial genus Mycobacterium. It is a variation of a method developed by Robert Koch in 1882.
Why do mycobacteria react differently in the acid fast stain than other bacteria?
Why do mycobacteria react differently in the acid-fast stain than other bacteria? Mycobacteria reacts differently in the acid fasting than other bacterias because Mycobacteria has mycolic acids in its cell wall which keeps the carbol fuchsin dye in the cell wall.
What is modified acid fast stain?
A modified acid-fast staining method was developed for rapid detection of Mycobacterium tuberculosis and its L forms, wherein carbol fuchsin and dioxogen were mixed into the sputum smear. With this method, the dyeing time is shortened and heating is not required.
Which of the following is a fluorescent stain for mycobacteria?
Rhodamine auramine stain is used for the detection of mycobacteria directly from clinical specimens. The dye binds with the mycolic acids and fluoresces under ultraviolet light. Acid fast organisms (mycobacteria) will appear yellow or orange under ultraviolet light.
Why can heat be eliminated in the kinyoun modification that you used?
Why can heat be eliminated in the Kinyoun modification that you used? The mycobacterium wax-like lipid is resistant to staining, so heat allowed penetration of the stain. The kinyoun modification does not require heat because a more concentrated fuchsin is used.
