1. Just a Sore Throat or Strep Slideshow
2. Take the Strep Throat Infection Quiz!
3. Infectious Mononucleosis Slideshow

Medical Author:

John Mersch, MD, FAAP

John Mersch, MD, FAAP

Dr. Mersch received his Bachelor of Arts degree from the University of California, San Diego, and prior to entering the University Of Southern California School Of Medicine, was a graduate student (attaining PhD candidate status) in Experimental Pathology at USC. He attended internship and residency at Children's Hospital Los Angeles.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• Strep throat facts
• What is strep throat?
• What causes a sore throat?
• What are tonsils and tonsillitis?
• What are pharynx and pharyngitis?
• Viral causes of throat infection
• Bacterial causes of throat infection
• How common is strep throat?
• Is strep throat contagious?
• What are the signs and symptoms of strep throat?
• Are strep throat symptoms different in children compared to adults?
• When should I be concerned about a possible strep throat?
• How is strep throat diagnosed?
• Who should be tested for strep throat?
• How is strep infection treated?
• How can viral throat infection be treated?
• Are there any recommended strep throat remedies and symptom reducers?
• When should the tonsils be removed?
• Why is it very important to detect and treat a strep throat?
• What are the potential complications of untreated strep throat infection?
• Is there a vaccine for strep throat?
• Can strep throat be prevented?
• Just a Sore Throat or Strep - Slideshow
• Take the Strep Throat Infection Quiz!
• Infectious Mononucleosis - Slideshow
• Strep Throat (Streptococcal) Infection FAQs
• Patient Comments: Strep Throat - Diagnosis
• Patient Comments: Strep Throat - Treatment
• Patient Comments: Strep Throat - Home Remedies for Symptoms
• Patient Comments: Strep Throat - Length Symptoms Lasted
• Strep Throat Index

Possible complications of untreated or partially treated strep throat infection are:

• rheumatic fever (described below);
• glomerulonephritis (described below);
• otitis media (spread of infection to the middle ear);
• meningitis (spread of infection to the lining of brain and spinal canal);
• pneumonia (lung infection);
• toxic shock syndrome (a rare but severe complication of strep pharyngitis, causing severe widespread infection and organ failure); and/or
• abscess formation around the tonsils and behind the throat (peri-tonsillar abscess and retro-pharyngeal abscess).

Formation of an abscess behind the throat (retro-pharyngeal abscess) due to untreated or under-treated strep throat infection can lead to severe illness causing pain in throat and neck, difficulty swallowing, and potential respiratory compromise. These abscesses may need to be drained by an ear-nose-throat (ENT) specialist urgently, and hospitalization may be required.

There is also a condition called Pediatric Autoimmune Neuropsychiatric Disorder associated with group A Streptococcus infection (PANDAS). This is a somewhat controversial condition linking group A strep infection in children with possible development and/or exacerbation of obsessive compulsive disorders or tic disorders (Tourette's syndrome) in children.

Acute rheumatic fever (ARF) is a serious complication of strep throat. It is thought that if the strep throat infection is untreated or inadequately treated by antibiotics, the bacteria remain in the tonsils and promote a persistent immune response from the body. Certain strains of the bacteria are more likely than others to cause this response. At times, this ongoing immune response may trigger the immune system to mistakenly attack other organs in the body including the joints (causing inflammation of the joints or arthritis) and the heart valves. The involvement of heart valves can cause damage of the heart valves and potential heart failure.

Treatment with appropriate antibiotics, even if started several days after the resolution of the infection, may prevent acute rheumatic fever. Fortunately, acute rheumatic fever it is now less common than in the pre-antibiotic era.

A similar immune process to acute rheumatic fever may involve the kidneys and result in kidney inflammation called post-streptococcal glomerulonephritis (PSGN). There is unfortunately no evidence that treatment of strep throat will prevent this condition. Children under the age of seven are at the highest risk of developing PSGN after an episode of strep throat. This condition is more common but less ominous than rheumatic fever. It typically resolves spontaneously after a few, weeks and generally does not lead to permanent kidney damage.