Skin or mucosal biopsy culture

Definition

Skin or mucosal biopsy culture is a laboratory test to isolate and identify organisms that cause infection. The test is performed on a sample obtained from the skin or mucous membranes.

Alternative Names

Why the Test is Performed

The test may be performed as part of the diagnosis of acute or chronic infections of the skin or mucous membranes.

How the Test is Performed

The skin or mucous-membrane sample can be taken in three ways: a shave biopsy (scraping or shaving a thin layer), a punch biopsy (using a needle or punch to obtain a small, but deeper, sample), or an excision of tissue (cutting to remove a piece of tissue).

A small piece of skin or mucous membrane is obtained and placed in culture media in the laboratory. It is observed for the growth of microorganisms such as bacteria and fungus. When growth is observed, the microorganisms can be identified and classified.

How to Prepare for the Test

The preparation is the same as for a skin biopsy. See also Gum biopsy.

How the Test Will Feel

You will be given local anesthesia to numb the site before the biopsy is done, but you may still feel some pain or discomfort.

Risks

There may be bleeding, slow healing, or an infection can be introduced into the biopsy site.

Considerations

Sometimes the biopsy is also sent for microscopic examination by a pathologist.

Normal Results

The presence of no organisms (a sterile biopsy) is normal.

What Abnormal Results Mean

Bacterial or fungal growth is present (infection).