Over the weekend Erin Brockovich made the news yet again as she and her nonprofit team descended on the village of Le Roy, N.Y., determined to test for environmental toxins that might be giving the town's teenagers symptoms of Tourette's syndrome. She has reportedly been stonewalled thus far by local officials, who have already ruled out toxins as the cause of last October's sudden outbreak of tics and involuntary movements in 12 girls who attend Le Roy Junior–Senior High School. An environmental testing company surveyed the air and water and found nothing amiss, and a local neurologist concluded upon examining the girls that they had "conversion disorder," a catchall moniker for physical symptoms that originate in the mind because of stress, trauma or even mass hysteria.
But many of the affected kids, their parents, concerned locals and outside experts are unhappy with that diagnosis, especially as the number of teens with symptoms has risen to 15 in recent weeks. Some experts think the doctors should revisit the idea that the teenagers might have PANS—pediatric acute-onset neuropsychiatric syndrome.
PANS is a new name for an old idea: that infections by bacteria, viruses or parasites can cause the sudden onset of neuropsychiatric ailments such as Tourette's and obsessive-compulsive disorder (OCD). (Tic disorders like Tourette's are closely related to OCD, sharing many symptoms and often coexisting in patients.) PANS is more commonly known by its former name, PANDAS—pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection—because the first known cases were in kids who had strep throat and then suddenly developed OCD. But researchers have realized in recent years that a variety of infectious agents—not just strep—can cause mental illness.
New Jersey–based doctor Rosario Trifiletti, who specializes in PANS, visited Le Roy, about 50 kilometers southeast of Rochester, last weekend to take blood and tissue samples from some of the afflicted girls, so he can test for such an infection. The results of those tests will be ready in a couple weeks. In the meantime, OCD expert Michael Jenike, a professor of psychiatry at Harvard Medical School, explains what PANS is and why it might account for the mysterious illness in Le Roy.
[An edited transcript of the interview follows.]
What is PANDAS, and why is it now called PANS?
It's the sudden onset of a neuropsychiatric disorder: OCD, anorexia or psychosis, cognitive problems. Initially, PANDAS was associated with strep. It turns out that other infections like mycoplasma, certain viruses, Lyme disease—these also produce the same thing. So it's not necessarily associated with strep, and they changed the name to reflect that. Now it's any sudden-onset neuropsychiatric disease.
I've even seen it in old people after they have mono, they suddenly have OCD. I've seen a lot of it after Lyme disease now, too.
How can an infection cause a mental illness?
It's an autoimmune issue. Mady Hornig at Columbia University has a mouse model that shows how it works. They give strep to mice, then give them another agent that breaks down the blood–brain barrier, and that induces a neuropsychiatric syndrome: the mice have trouble running mazes, and so on. Then they purify the antibodies from those mice, inject them in another mouse that never had strep, and that mouse gets the neuropsychiatric symptoms, too. That shows it's the antibodies doing the damage.