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Gram stain of tissue biopsy

Gram stain of tissue biopsy

Overview

The gram stain procedure is a method of staining microorganisms on a slide using crystal violet to be viewed later under a microscope.

Review Date 12/4/2022

Updated by: Jatin M. Vyas, MD, PhD, Associate Professor in Medicine, Harvard Medical School; Associate in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.