How It Is Done continued...

A needle may be used to collect fluid from a wound that is covered (scabbed-over) or from an abscess. The fluid is then placed in the culture tube.

Your doctor may need to remove a sample of skin or tissue (biopsy) for testing. If collecting the sample is likely to cause pain, you may be given a shot to numb the area (local anesthetic) first.

Once a sample is collected, it is placed in a container with a substance (called growth medium or culture medium) that helps bacteria, fungus, or viruses grow.

• Bacteria usually need about one to two days to grow.
• Fungi usually need several days to grow.
• Viruses need to be placed in a container with living cells and can take weeks to grow.

Any bacteria, fungi, or viruses that grow will be identified with a microscope, chemical tests, or both. If sensitivity testing is done to help make decisions about treatment, more time will be needed.

How It Feels

If you have a sample of fluid or tissue collected from a wound, you may feel some pain when the sample is collected. You may feel a short, sharp sting if you are given a shot of anesthetic to numb the area where the culture sample will be taken.

Risks

There is a very slight risk of spreading some infections if a biopsy is needed to collect the sample.

Results

A skin or wound culture is a test to find and identify germs (such as bacteria, a fungus, or a virus) that may be growing on the skin or in a wound.

Some types of bacteria, fungi, and viruses grow quickly in culture, and some grow slowly. Test results may take from one day to several weeks, depending on the type of infection suspected.

If test results are positive, sensitivity testing may be done help make decisions about treatment.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Taking antibiotics or just finished taking them.
• Getting bacteria that is normally found on the skin in the tissue or wound sample.