Throat swab culture
A throat swab culture is a laboratory test done to identify germs that may cause infection in the throat. It is most often used to diagnose strep throat.
Throat culture and sensitivity; Culture - throat
How the test is performed
You will be asked to tilt your head back and open your mouth wide. The health care provider rubs a sterile cotton swab along the back of your throat near the tonsils. You need to resist gagging and closing the mouth while the swab touches this area.
The health care provider may need to scrape the back of the throat with the swab several times. This helps improve the chances of detecting bacteria.
How to prepare for the test
Do not use antiseptic mouthwashes before the test.
How the test will feel
Your throat may be sore at the time the test is taken. You may experience a gagging sensation when the back of your throat is touched with the swab, but the test only lasts a few seconds.
Why the test is performed
The test is performed when a throat infection is suspected, particularly strep throat
. A throat culture can also help your health care provider determine which antibiotics will work best for you.
A normal or negative result means no bacteria or other germs that may cause a sore throat were found.
What abnormal results mean
An abnormal or positive culture result means bacteria or other germs that can cause a sore throat were seen on the throat swab.
What the risks are
This test is safe and well-tolerated. In very few patients, the sensation of gagging may lead to an urge to vomit or cough.
Wessels MR. Clinical practice. Streptococcal pharyngitis. N Engl J Med. 2011;364(7):648-655.
Weber R. Pharyngitis. In: Bope ET, Kellerman RD, eds. Conn’s Current Therapy 2012. 1st ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 1.
Nussenbaum B, Bradford CR. Pharyngitis in adults. In: Flint PW, Haughey BH, Lund LJ, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2010:chap 13.
Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.