PrintA sample of skin, hair, fingernails, or toenails is obtained using a scalpel or other instrument. The specimen is sent to a laboratory so that it can be grown in a suitable culture medium to identify potential infectious organisms.
Purpose of the Skin, Hair, or Nail Culture
- To determine whether an abnormality of the skin, hair, or nails is caused by a bacterial, fungal, mycobacterial, or viral infection
Who Performs It
- A doctor
Special Concerns
- Previous therapy with antibacterial, antifungal, or antiviral drugs may lead to false-negative results.
- The herpes zoster virus (which causes chicken pox and shingles) is very fragile and almost never grows in a culture, in some cases leading to false-negative results.
- Certain bacteria or fungi that are cultured may not in fact be responsible for the infection, leading to false-positive results.
Before the Skin, Hair, or Nail Culture
- No special preparation is required.
What You Experience
- If your skin is the site of the suspected infection, the doctor scrapes the outer layer of abnormal skin with a scalpel.
- When the scalp is affected, the doctor gently removes diseased hairs with a forceps and also scrapes your scalp with a scalpel.
- For nail infections, the examiner scrapes the inner surface of the nail below the tip or clips off the portion of the nail that appears abnormal.
- You may experience some minor discomfort while the sample is being collected.
- Sample collection usually takes only about 1 minute.
Risks and Complications
- None
After the Skin, Hair, or Nail Culture
- You may resume your normal activities.
Results
- The skin, hair, or nail specimen is placed in culture media in the laboratory and is then observed for the growth of microorganisms.
- If organisms are observed growing in culture, they are identified and classified to provide a definitive diagnosis, and appropriate therapy is begun.
- If the test is negative but the problem persists, your doctor may test another tissue sample.
Source:
The Johns Hopkins Consumer Guide to Medical Tests
Simeon Margolis, M.D., Ph.D., Medical Editor
Updated by Remedy Health Media
