(NEW YORK) -- On Dec. 19, 2011, Lori Brownell, who was 17 at the time, shot a YouTube video of herself as she talked about the tics she'd developed weeks earlier. She twitched her body, fluttered her fingers and made noises in her throat as she described her fainting and seizing episodes.
"When I do this, there's this weird feeling that goes up and down my spinal column," she explained to the camera shortly before going into a fit of clapping.
"If anyone wants to talk about this or if anyone's starting it, I'll be willing to talk," she said, signing off on the video that would eventually get more than 250,000 hits.
She would soon make national news.
Within a few months, 18 high school girls and one boy in western New York came down with the same Tourette's syndrome-like symptoms as Brownell's, sparking a national media frenzy and a medical mystery. Although Brownell lives in Corinth, N.Y., she became lumped in with the majority of the tic-ing girls 250 miles away in Le Roy, because she'd driven through the town with a friend on her way to a softball game in Ohio.
As the Le Roy girls appeared on talk shows, one doctor suggested they had Pandas, a pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections. Another doctor suggested the tics were caused by the HPV vaccine Gardasil. Soon, famed environmental activist Erin Brockovich said she suspected groundwater contamination from a 40-year-old chemical spill caused the tics.
One by one, the theories were dismissed.
Fourteen of the 19 tic-ing patients sought treatment at Dent Neurologic Institute, where they were eventually diagnosed with mass psychogenic illness, a rare form of conversion disorder in which an emotional response to stress can manifest in physical symptoms, such as tics. They have all since recovered, their doctor, Dr. Jennifer McVige, told ABC News.
But not Brownell. Brownell's mother did not want to send her to Dent because it had diagnosed the other girls with conversion disorder -- a diagnosis experts said patients often greet with denial.
Instead, Brownell and her mother say they believe "chronic" Lyme disease, a controversial diagnosis, caused Brownell's tics and may even have caused the Le Roy girls' tics, too.
But most doctors -- and insurance providers -- say there's no such thing as "chronic" Lyme disease, and that Lyme disease doesn't cause Tourette's syndrome-like tics.
"The short answer is you won't find that in medical texts," said Dr. William Schaffner, a former president of the National Foundation for Infectious Diseases. "Since Lyme disease has been studied with enormous care and thoroughness, the literature on Lyme first described 35 or 40 years ago now fills half a room. Its clinical manifestations are extremely well known. I think this is an unlikely cause of this single girl's illness."
Still, Brownell has been on intravenous antibiotics to treat Lyme disease for nearly a year.
Conversion disorder is diagnosed by ruling out all physical causes for an ailment, and it's curable, said Dr. Elizabeth Bowman, a psychiatry professor at Indiana University who has treated 1,000 patients with psychogenic, nonepileptic seizures -- a kind of conversion disorder -- during her 20-year career.
But many patients react to the diagnosis with denial and ask for more tests.
"People don't like to hear that they have conversion disorder," Bowman said. "The thing with any mental illness is that they think it means they're quote 'crazy,' and they're not. They're stressed. They're hurt. Deep in your brain, a message is coming out that's like an SOS sent in the language of the body. It's encoded."
Although Brownell was honored with the Tick-Borne Disease Alliance's Courage Award this month, Schaffner said groups often peg symptoms to the wrong illness in an attempt to explain them.
"Then, when science doesn't bear out, it's very difficult for people to accept that," he said, adding that "chronic" Lyme disease was an example of this.
Schaffner, who heads Vanderbilt University's department of preventive medicine, said doctors at the Infectious Disease Association of America concluded that the bacterium that causes Lyme is killed off after a week or two of antibiotics. It doesn't linger and cause recurring or worsening symptoms.
"That syndrome doesn't exist," Schaffner said of "chronic" Lyme disease.
According to the Centers for Disease Control and Prevention, more research is being done on what it calls "post-treatment Lyme disease syndrome" rather than "chronic Lyme disease," because only some symptoms, rather than the bacterium, persist. Lingering symptoms include "fatigue, pain or joint and muscle aches," but they don't persist for more than a few months.
Although Brownell's doctor prescribed long-term intravenous antibiotics to be delivered through a semi-permanent opening in her arm called a PICC line, the CDC said studies have found that long-term antibiotics don't work any better than placebos. In fact, a 30-year-old woman, whose case was published in the Oxford Journal Clinical Infectious Diseases, died in 1999 from complications of a 27-month IV antibiotic regimen for an "unsubstantiated diagnosis of chronic Lyme disease."
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