How to cite this article: Panicker V, Nayak P, Krishna R, Sreenivaasan N, Thomas J, Sreedevan V, et al. Gram stain. J Skin Sex Transm Dis doi: 10.25259/JSSTD_22_2022.
Gram staining is a differential staining technique performed when a bacterial infection is suspected. The technique classifies bacteria into two broad groups: Gram negative and gram positive bacteria. In this net educational video, we have demonstrated the method of Gram staining.
Clinical suspicion of bacterial infection.
Preparation of the smear
An inoculation loop is used to transfer a drop of suspended culture to the microscope slide, smeared as a thin film, and either air-dried or over a gentle flame.
INTERPRETATION OF THE RESULTS
Gram stain differentiates bacteria based on the differential staining properties of bacterial cell wall. Bacteria with thick peptidoglycan layer stains blue to purple and are treated as gram positive, while bacteria with thin peptidoglycan layer stains red to pink and are treated as gram negative.
We are grateful to Dr. Fairoz CP (Assistant Professor, Department of Microbiology) and Dr. Mohammed Althaf V (Junior Resident, Department of Dermatology), Government Medical College, Kozhikode, for the images of Gram-positive and Gram-negative organisms, respectively. Background music used in the video is under a creative commons license. (Music by Whitesand - Eternity https://www.youtube.com/watch?v=X5c83Uixoj8, https://www.youtube.com/c/WhitesandComposer/).
Declaration of patient consent
Not required as there are no patients in this article.
Financial support and sponsorship
Conflicts of interest
Dr. Vinitha Panicker and Dr. Soumya Jagadeesan are on the editorial board of the Journal.