A streptococcal screen is a test to detect group A streptococcus, the most common cause of strep throat.
Alternative Names
Rapid strep test
How the test is performed
The test requires a throat swab. It takes about 7 minutes. The swab is tested to identify group A streptococcus, the cause of strep throat.
How to prepare for the test
There is no special preparation. Inform the health care provider if you are taking, or have recently taken, antibiotics.
How the test will feel
Your throat will be swabbed in the area of the tonsils. This may make you gag.
Why the test is performed
Your health care provider may order this test if you have signs of strep throat, which include:
Fever
No coughing
Tender and swollen glands in the front of the neck
White or yellow spots on the tonsils
Normal Values
A negative strep screen most often means Group A streptococcus is not present. It is unlikely that you have strep throat.
If your health care provider still feels that you may have strep throat, a throat culture will be done.
What abnormal results mean
A negative strep screen most often means Group A streptococcus is present, and confirms strep throat.
At times, the test may be positive even if you do not have strep. This is called a false-positive result and is more likely if you have a fever or the symptoms of strep throat.
What the risks are
There are no risks.
Special considerations
This test screens for the group A streptococcus bacteria only and will not detect other causes of sore throat.
References
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.
Review Date:
5/15/2012
Reviewed By:
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.
