The discovery of PANDAS came through observing the reactions of patients. Initially, Swedo’s team noticed a group of patients who were ill with infections and then suddenly developed dramatic psychiatric symptoms. At first, they were not sure streptococcus was the culprit but research soon isolated the strep antibodies as an important focus of interest.

PANDAS is controversial in medical circles with some physicians questioning whether such extreme psychiatric symptoms can be triggered by strep antibodies. However, according to Dr. Swedo, there is little doubt that the body’s efforts to fight the strep bacteria set off a chain of events leading to PANDAS symptoms. “The science is clear now,” Swedo asserts. “We not only have a direct relationship between the anti-strep antibodies and the anti-neuronal antibodies, but also have demonstrated that the antibodies interact with receptors in the brain that could produce the symptoms observed.”  

Normally when the strep bacteria enter the body, they defend themselves by mimicking healthy cells and elude detection by the immune system. Using the stealth strategy, the strep bacteria create an infection. In response, the body naturally creates antibodies – cellular components designed to find the bacteria, bind with them and direct the immune system to destroy the bacteria. When this happens as designed, the antibodies find the strep bacteria and the immune system wins the battle.

However, antibodies are not terribly discriminating and sometimes cannot tell a streptococcus bacterium apart from a healthy cell. In some children, these antibodies pass into the brain and look for something to connect with. In PANDAS, the strep antibodies are unable to discriminate between strep and healthy brain cells. However, the union of strep antibody and neural tissue is not a match made in heaven. Recent research, reported last fall by University of Oklahoma researcher, Madeleine Cunningham, suggests that the antibodies connect with parts of the brain which regulate repetitive behaviors and movement, such as compulsions and tics. According to Dr. Swedo, such autoimmune actions may have the direct result of producing obsessions, compulsions and tics; and in addition, they might indirectly offset the critical balance of brain chemistry which regulates mood and emotion.

Compounding the problem is the durability of strep antibodies. They can remain on the prowl for a hook up weeks after the strep is gone. Subsequent infections or even colds can stimulate the immune system to produce more of the same kind of antibodies which the triggered the original symptoms. PANDAS children can then abruptly re-experience the same symptoms after a symptom-free span of time. Dr. Swedo explained, “We see a saw-toothed pattern of symptoms, extreme outbursts of behaviors for a brief period in response to the infections and then the child may be relatively symptom-free for a period of time.”  

What can parents do?

The primary advice for parents is to treat strep throats promptly. This means a visit to the primary care provider at the first signs of strep throat. Symptoms of strep throat include:

  • Severe and sudden sore throat without coughing, sneezing, or other cold symptoms,
  • pain or difficulty with swallowing,
  • high fever,
  • swollen lymph nodes in the neck,
  • white or yellow spots or coating on the throat and tonsils,  
  • bright red throat or dark red spots on the roof of the mouth at the back near the throat and/or swollen tonsils, although this symptom may also be caused by a viral infection.
  • Vomiting without diarrhea, headache and other nonspecific signs of illness can also signal a strep infection.   

Some children dislike having a throat culture done and will deny that they are in pain, rather than risk getting “the swab.” However, for reasons other than PANDAS (e.g., rheumatic fever), it is important to investigate and treat these symptoms promptly. For some children, the sudden PANDAS behavioral changes are the tipoff that an otherwise unclear symptom picture is really strep throat. Thus, any sudden changes in behavior should involve a trip to the pediatrician to rule out a biological trigger.  

While it is tempting to keep children who are vulnerable to post-strep behavioral symptoms on antibiotics, this is not the preferred course. The antibodies themselves are not altered by antibiotic medication and so, antibiotics cannot shorten the course of obsessions, compulsions or tics. For severe cases, parents and physicians might consider using immunoglobulin treatment (IVIG) or plasmapheresis.  IVIG administration produces a vigorous immune response that appears to counteract the PANDAS symptoms.  Plasmapheresis cleans the strep antibodies (and others) from the blood via plasma exchange.  These interventions are considered experimental and are not without side-effects.  In addition, they are expensive and insurance companies often won't pay for this "off-label" use of the treatments.  However, for extremely symptomatic children, the procedure may offer relief.