Kids who were once happy children are suddenly developing bizarre behavior.
Involuntary ticks and violent fits of rage are the dangerous side effects of PANDAS, a disorder brought on by strep.
"PANDAS is Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections," said Dr. Dean Klug.
"I wish I didn't have PANDAS," said Garrett Nass, 11, who developed a tic after fighting an ear infection at age five.
"And he would do this and it would be like that every so often he would do that," said Catherine Nass, Garrett's mother.
More than two years and a multitude of behavioral tests later, doctors found a strep infection in his blood, even though he had never had strep throat.
"Instead of his antibodies attacking the strep, it was attacking his brain, which was causing the OCD and the tics," said Catherine.
PANDAS actually attacks the immune system, which wreaks havoc on the brain, often leading to a mis-diagnosis because PANDAS mimics many psychological disorders.
Children can suffer for years before getting the proper treatment.
"When they were treated with antibiotics, the behaviors diminished or actually disappeared," said Dr. Klug. "So there was felt to be a connection. And with repeated infections and with these disturbing behaviors, it was found that in many cases by getting the tonsils removed that these behaviors could be resolved."
Garrett will be on antibiotics for the rest of his life.
In Jackson, Mississippi, Haley Clardy is speaking out about her 10-year-old daughter.
"She tried to choke me driving down the road," said Clardy, “said she wanted to kill herself, cut her head off."
The mother of 17-year-old Grant Acord, the Oregon teen accused of planning to bomb his high school, said he “suffers from PANDAS.”
The PANDAS disorder primarily affects young children and comes on suddenly. If your child develops any of the symptoms you’ve just seen, ask your doctor about a strep test. Other autoimmune diseases can also trigger OCD and need to be ruled out.