Gram stain of tissue biopsy

Alternative names:

tissue biopsy gram stain

How the test is performed:

A sample called a smear from tissue specimen is applied in a very thin layer to a microscope slide. The specimen is stained with a violet stain known as a gram stain and then examined under the microscope for the presence of bacteria. The color, number, and morphologic appearance of the cells help make it possible to identify the genus (type) of the organism.

How to prepare for the test:

If the biopsy is included as part of a surgical procedure, food and fluid will be withheld overnight. If the biopsy is of a superficial tissue, food and fluid may be withheld for several hours before the procedure.

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

• infant test or procedure preparation (birth to 1 year)
• toddler test or procedure preparation (1 to 3 years)
• preschooler test or procedure preparation (3 to 6 years)
• schoolage test or procedure preparation (6 to 12 years)
• adolescent test or procedure preparation (12 to 18 years)

How the test will feel:

How the test feels depends on the part of the body being biopsied. There are several different methods for obtaining tissue samples. A needle may be inserted through the skin to the specific tissue. An incision through the skin into the tissue may be made with a small excision of the specific tissue. A biopsy may also be taken from inside the body by an instrument that visualizes the inside of the body such as an endoscope or cystoscope. Some type of anesthetic is usually given. Pressure rather than pain is the usual sensation.

Why the test is performed:

The test is performed when an infection of a body tissue is suspected.