Although strep throat itself isn't dangerous, it may lead to serious complications — sometimes even with treatment.

Spread of infection

Strep bacteria may spread, causing infection in your:

  • Tonsils
  • Sinuses
  • Skin
  • Blood
  • Middle ear

Inflammatory reactions

Strep infection may lead to other inflammatory illnesses, including:

  • Scarlet fever, an illness characterized by a rash
  • Inflammation of the kidney (poststreptococcal glomerulonephritis)
  • Rheumatic fever, a serious condition that can affect the heart, joints, nervous system and skin

Researchers are investigating a possible link between strep infection and a rare condition called Pediatric autoimmune neuropsychiatric disorder associated with group A streptococci (PANDAS). PANDAS is a term used to describe certain children whose symptoms of neuropsychiatric conditions, such as obsessive compulsive disorder or tic disorders, are exacerbated by strep infection.

Dec. 20, 2012