Consider this scenario: You are the parent of a six year-old child. He recently had strep throat, but is feeling better. One morning, his screaming wakes you up. You can’t calm him down or completely follow what he is talking about, but it has something to do with germs and fear and danger. The morning is consumed with attempts to comfort him and try to understand what is going on. Getting to school isn’t an option, which is highly unusual for him. Over the next few days, it gets worse. He washes his hands until they bleed, and refuses to eat because he says the food is contaminated.
It’s possible that his strep infection triggered sudden-onset obsessive compulsive disorder (OCD). Quick treatment with antibiotics can reverse the problem.
Infectious disease and mental health experts call this pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS for short). This controversial and seemingly rare diagnosis was given to children who abruptly developed obsessive compulsive disorder or tic disorders such as Tourette’s syndrome after contracting infections caused by group A streptococcus bacteria, such as strep throat or scarlet fever.
The first cases of PANDAS were described in 1998. Since then, experts have recognized that other infectious organisms besides group A streptococcus bacteria can cause sudden-onset OCD or tics. In a paper published last week in the medical journal Pediatrics & Therapeutics, Dr. Susan Swedo and her colleagues detailed this new understanding and recommended creating a more comprehensive diagnosis: pediatric acute-onset neuropsychiatric syndrome (PANS). Dr. Swedo is Chief of the Pediatrics and Developmental Neuroscience Branch at the U.S. National Institute of Mental Health.
How can an infection do this?
What we think is happening to these children is that antibodies to the infectious agent cross the barrier that protects the brain from what’s circulating in the bloodstream. Once inside the brain, the antibodies inflame a structure called the basal ganglia. The basal ganglia controls various functions, including fine motor movements (like handwriting), thinking, emotion, and learning routine behaviors or habits. It may also play a role in the development of OCD.