How is tonsillitis diagnosed?

To diagnosis tonsillitis, your doctor will:

  • Examine your throat for redness, swelling or white spots on the tonsils
  • Ask about other symptoms you’ve had, such as a fever, cough, runny nose, rash or stomachache
  • Look in your ears and your nose for other signs of infection
  • Feel the sides of your neck to see if the lymph nodes are swollen and tender

After confirming a tonsillitis diagnosis, your doctor will need to determine whether the infection results from a virus or bacteria (strep throat).

How is strep throat diagnosed?

Your doctor may order a throat culture — also known as a strep test — to determine if you have strep throat. A throat culture is a simple test that checks for the presence of specific bacteria in your throat. During a throat culture:

  1. Your doctor will swipe the back of your throat with a long cotton swab to gather saliva and cells. The test may feel uncomfortable, but it is not painful.
  2. While you wait, your doctor will test the cells to check for bacteria. This test is called a “rapid strep test.” The results are ready in about 10-15 minutes.
  3. If the results are positive and the test does detect bacteria, your doctor will prescribe an antibiotic to treat you for strep throat.
  4. If the results are negative and the rapid strep test does not detect bacteria, your doctor may send the sample away to a lab for more thorough testing. This longer lab test usually takes 2-3 days to get results.
  5. If the lab test results come back negative, you’ll know the tonsillitis is viral, not bacterial.

How do I know if I have tonsillitis?

If you have a sore throat, swollen tonsils and pain with swallowing, you may have tonsillitis. You should visit your doctor to determine whether bacteria or a virus is causing the tonsillitis. The treatment varies based on the type of infection.

Last reviewed by a Cleveland Clinic medical professional on 06/11/2019.


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