Gram stain of skin lesion

Alternative names:

skin lesion gram stain

How the test is performed:

A sample called a smear from a skin lesion scraping or skin lesion biopsy 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 make it possible to identify the type of organism present.

How to prepare for the test:

Adult:
There is no special preparation. The test is often performed in a health care provider's office.

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:

A scraping or biopsy of the skin lesion will be taken. The skin area will be cleansed to avoid contamination with bacteria on the surface of the skin. A local anesthetic may be injected into the skin if a biopsy is taken. A pin-prick sensation may be felt as the anesthetic is injected. There may be a sensation of pressure at the site of the scraping or biopsy.

Why the test is performed:

The test is performed to determine if infection is present in a skin lesion, and if so, the causative bacteria.