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Bacteria Culture Test

What is a Bacteria Culture Test?

Bacteria are a large group of one-celled organisms. They can live on different places in the body. Some types of bacteria are harmless or even beneficial. Others can cause infections and disease. A bacteria culture test can help find harmful bacteria in your body. During a bacteria culture test, a sample will be taken from your blood, urine, skin, or other part of your body. The type of sample depends on the location of the suspected infection. The cells in your sample will be taken to a lab and put in a special environment in a lab to encourage cell growth. Results are often available within a few days. But some types of bacteria grow slowly, and it may take several days or longer.

What is it used for?

Bacteria culture tests are used to help diagnose certain types of infections. The most common types of bacteria tests and their uses are listed below.

Throat Culture

  • Used to diagnose or rule out strep throat
  • Test procedure:
    • Your health care provider will insert a special swab into your mouth to take a sample from the back of the throat and tonsils.

Urine Culture

  • Used to diagnose a urinary tract infection and identify the bacteria causing the infection
  • Test procedure:
    • You will provide a sterile sample of urine in a cup, as instructed by your health care provider.

Sputum Culture

Sputum is a thick mucus that is coughed up from the lungs. It is different from spit or saliva.

  • Used to help diagnose bacterial infections in the respiratory tract. These include bacterial pneumonia and bronchitis.
  • Test procedure:
    • You may be asked to cough up sputum into a special cup as instructed by your provider; or a special swab may be used to take a sample from your nose.

Blood Culture

  • Used to detect the presence of bacteria or fungi in the blood
  • Test procedure:
    • A health care professional will need a blood sample. The sample is most often taken from a vein in your arm.

Stool Culture

Another name for stool is feces.

  • Used to detect infections caused by bacteria or parasites in the digestive system. These include food poisoning and other digestive illnesses.
  • Test procedure:
    • You will provide a sample of your feces in a clean container as instructed by your health care provider.

Wound Culture

  • Used to detect infections on open wounds or on burn injuries
  • Test procedure:
    • Your health care provider will use a special swab to collect a sample from the site of your wound.

Why do I need a bacteria culture test?

Your health care provider may order a bacteria culture test if you have symptoms of a bacterial infection. The symptoms vary depending on the type of infection.

Why do I have to wait so long for my results?

Your test sample doesn't contain enough cells for your health care provider to detect an infection. So your sample will be sent to a lab to allow the cells to grow. If there is an infection, the infected cells will multiply. Most disease-causing bacteria will grow enough to be seen within one to two days, but it can take some organisms five days or longer.

Will I need to do anything to prepare for the test?

There are many different types of bacteria culture tests. Ask your health care provider if you need to do anything to prepare for your test.

Are there any risks to the test?

There are no known risks to having a swab or blood test or to providing a urine or stool sample.

What do the results mean?

If enough bacteria is found in your sample, it likely means you have a bacterial infection. Your health care provider may order additional tests to confirm a diagnosis or determine the severity of the infection. Your provider may also order a "susceptibility test" on your sample. A susceptibility test is used to help determine which antibiotic will be most effective in treating your infection. If you have questions about your results, talk to your health care provider.

References

  1. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Bacterial Sputum Culture: The Test; [updated 2014 Dec 16; cited 2017 Mar 4]; [about 3 screens]. Available from: https://labtestsonline.org/understanding/analytes/sputum-culture/tab/test/
  2. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Bacterial Sputum Culture: The Test Sample; [updated 2014 Dec 16; cited 2017 Mar 4]; [about 2 screens]. Available from: https://labtestsonline.org/understanding/analytes/sputum-culture/tab/sample/
  3. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Bacterial Wound Culture: The Test; [updated 2016 Sep 21; cited 2017 Mar 4]; [about 3 screens]. Available from: https://labtestsonline.org/understanding/analytes/wound-culture/tab/test/
  4. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Bacterial Wound Culture: The Test Sample; [updated 2016 Sep 21; cited 2017 Mar 4]; [about 2 screens]. Available from: https://labtestsonline.org/understanding/analytes/wound-culture/tab/sample/
  5. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Blood Culture: At a Glance; [updated 2015 Nov 9; cited 2017 Mar 4]; [about 1 screen]. Available from: https://labtestsonline.org/understanding/analytes/blood-culture/tab/all/#2
  6. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Blood Culture: The Test; [updated 2015 Nov 9; cited 2017 Mar 4]; [about 3 screens]. Available from: https://labtestsonline.org/understanding/analytes/blood-culture/tab/test
  7. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Blood Culture: The Test Sample; [updated 2015 Nov 9; cited 2017 Mar 4]; [about 2 screens]. Available from: https://labtestsonline.org/understanding/analytes/blood-culture/tab/sample/
  8. Lab Tests Online [Internet]. American Association for Clinical Chemistry; c2001–2017. Glossary: Culture; [cited 2017 May 1]; [about 3 screens]. Available from: https://labtestsonline.org/glossary/culture
  9. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Stool Culture: The Test; [updated 2016 Mar 31; cited 2017 Mar 4]; [about 3 screens]. Available from: https://labtestsonline.org/understanding/analytes/stool-culture/tab/test
  10. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Stool Culture: The Test Sample; [updated 2016 Mar 31; cited 2017 Mar 4]; [about 2 screens]. Available from: https://labtestsonline.org/understanding/analytes/stool-culture/tab/sample/
  11. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Strep Throat Test: The Test Sample; [updated 2016 Jul 18; cited 2017 Mar 4]; [about 2 screens]. Available from: https://labtestsonline.org/understanding/analytes/strep/tab/sample/
  12. Lab Tests Online [Internet]. American Association for Clinical Chemistry; c2001–2017. Susceptibility Testing: The Test; [updated 2013 Oct 1; cited 2017 May 1]; [about 4 screens]. Available from: https://labtestsonline.org/understanding/analytes/fungal/tab/test/
  13. Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001–2017. Urine Culture: The Test; [updated 2016 Feb 16; cited 2017 Mar 4]; [about 3 screens]. Available from: https://labtestsonline.org/understanding/analytes/urine-culture/tab/test
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