Diagnosis
Your or your child's doctor may review the symptoms and medical history. He or she may conduct a physical exam that includes:
Using a lighted instrument to look at the throat, and likely the ears and nasal passages
Gently feeling the neck to check for swollen glands (lymph nodes)
Listening to your or your child's breathing with a stethoscope
Throat swab
In many cases, doctors use a simple test to detect streptococcal bacteria, the cause of strep throat. The doctor rubs a sterile swab over the back of the throat to get a sample of secretions and sends the sample to a lab for testing. Many clinics are equipped with a lab that can get a test result for a rapid antigen test within a few minutes. However, a second, often more reliable test, called a throat culture, is sometimes sent to a lab that returns results within 24 to 48 hours.
Rapid antigen tests aren't as sensitive, although they can detect strep bacteria quickly. Because of this, the doctor may send a throat culture to a lab to test for strep throat if the antigen test comes back negative.
In some cases, doctors may use a molecular test to detect streptococcal bacteria. In this test, a doctor swipes a sterile swab over the back of the throat to get a sample of secretions. The sample is tested in a lab. Your or your child's doctor may have accurate results within a few minutes.