Microbiology 49 = Identification of Bacteria (Part-04) = Acid Fast + Non Acid Fast Staining Method

Download "Solution Pharmacy" Mobile App to Get All Uploaded Notes, Model Question Papers, Answer Papers, Online Test and other GPAT Materials - https://play.google.com/store/apps/de...

Acid-fast bacteria, also known as acid-fast bacilli or simply AFB, is a group of bacteria sharing the characteristic of acid fastness. 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. This important and unique feature of certain bacteria gives us the ability to classify and detect them using relatively easy laboratory procedures such as microscopy

Acid-fast staining is another commonly used, differential staining technique that can be an important diagnostic tool. An acid-fast stain is able to differentiate two types of gram-positive cells: those that have waxy mycolic acids in their cell walls, and those that do not. Two different methods for acid-fast staining are the Ziehl-Neelsen technique and the Kinyoun technique. Both use carbolfuchsin as the primary stain. The waxy, acid-fast cells retain the carbolfuchsin even after a decolorizing agent (an acid-alcohol solution) is applied. A secondary counterstain, methylene blue, is then applied, which renders non–acid-fast cells blue.

Mycobacterium tuberculosis, the bacterium that causes tuberculosis, can be detected in specimens based on the presence of acid-fast bacilli. Often, a smear is prepared from a sample of the patient’s sputum and then stained using the Ziehl-Neelsen technique (Figure 5). If acid-fast bacteria are confirmed, they are generally cultured to make a positive identification. Variations of this approach can be used as a first step in determining whether M. tuberculosis or other acid-fast bacteria are present, though samples from elsewhere in the body (such as urine) may contain other Mycobacterium species.

Get in touch with the solution by just clicking the following links-

Facebook Group-   / solutionpharamcy  
Facebook Page-   / pharmavideo  
New Channel (Pharmacy Dictionary)    / @pharmacydictionary  
Instagram-   / solutionpharmacy  
E-Mail for official and other work - solutionpharmacy@gmail.com
LinkedIn-   / pushpendrakpatel  
#solutionpharmacy #Pharmacologyclass #Pharmacognosyvideos #GPATonlinetest #GPATclass #GPATvideos #Microbiologyclass#Microbiology#