Auramine- Rhodamine Staining


Auramine-rhodamine staining is a histological technique that uses fluorescent dyes to visualize acid-fast bacilli, especially Mycobacterium spp, under fluorescence microscopy . The dyes bind with the mycolic acid on the cell wall of the bacteria and make them appear reddish-yellow or orange . Mycolic acid is a long fatty acid that is essential for the survival of Mycobacterium spp and gives them the property of acid-fastness .

Auramine-rhodamine staining was developed as a modification of the Ziehl-Neelsen staining, which is another technique to stain acid-fast bacilli using heat and light microscopy . Auramine-rhodamine staining has several advantages over Ziehl-Neelsen staining, such as being faster, more affordable, more sensitive, and requiring no heat fixation . However, it is not as specific as Ziehl-Neelsen staining and may need confirmation by culture methods or other stains .

Auramine-rhodamine staining can also detect other acid-fast organisms like Cryptosporidium, which is a parasite that causes diarrhea . Therefore, this technique has various applications in microbiology, such as diagnosing tuberculosis, leprosy, and cryptosporidiosis .

In this article, we will compare auramine-rhodamine staining with Ziehl-Neelsen staining, explain the principle and reagents of auramine-rhodamine staining, describe the procedure and result interpretation of auramine-rhodamine staining, and discuss the applications, advantages, and limitations of auramine-rhodamine staining.