An autism summit in Dallas this weekend features a medical professional who has been disciplined for mistreating children and celebrities who shun science and claim vaccines are dangerous. Autism advocates say the event offers false hope to parents by promoting miracle cures and treatments proved to be dangerous and ineffective.

The Autism Education Summit is hosted by Generation Rescue, an organization co-founded by anti-vaccine advocate Jenny McCarthy, who has a son with autism. McCarthy will be joined by Bexar County District Attorney Nico LaHood, who also claims vaccines cause autism.

Organizers of the summit did not respond to an interview request.

The event includes training on hyperbaric oxygen therapy, which the Food and Drug Administration has not approved for the treatment of autism and which studies have found to be ineffective in people with the condition.

Two doctors who are featured speakers are facing lawsuits for using dangerous treatments that they claim reverse autism. Anjum Usman (who sometimes goes by Anju) and Daniel Rossignol were sued in Chicago by the parent of a 7-year-old boy with autism. The boy’s father, James Coman, said the doctors harmed his son using "dangerous and unnecessary experimental treatments."

Rossignol and Usman prescribed intravenous chelation treatments designed to rid the body of heavy metals. Chelation treatment is approved only for treating conditions such as lead poisoning and iron overload and even then, side effects can include high blood pressure, abnormal heart rhythms and low calcium, which can cause the heart to stop.

Rossignol prescribed the treatments over the phone without ever seeing the 7-year-old, the lawsuit said.

Studies have found that chelation does not cure autism and can be dangerous when used to treat the condition. In a study by researchers at Cornell University, rats with no lead exposure treated with a chelator often given to children with autism suffered long-term impairment of emotional regulation and brain function.

A 5-year-old boy died in Pennsylvania in 2005 during his third session of chelation treatment. He was treated by Dr. Roy Kerry, who believed the boy’s autism was caused by heavy metal poisoning. An autopsy showed the child’s death was caused by brain injury and heart damage due to a drop in calcium levels. Kerry voluntarily surrendered his medical license in 2008.

Usman and Rossignol are part of a group called Defeat Autism Now, which promotes so-called autism treatments that are discredited and disproved by science. Usman’s medical license has been put on probation.

Preying on the desperate

One in 68 children in the U.S. is diagnosed with autism spectrum disorder by age 8, according to the Centers for Disease Control and Prevention. That number has increased from 1 in 100 in recent years.

A study published last year found that a broader definition of autism could explain why more children are diagnosed with the disorder. While researchers cannot pinpoint the cause of autism, many agree that a number of factors including genes and environmental exposures probably interact and play a role in development of the condition.

Autism is characterized by repetitive behavior, difficulty engaging in social interactions and forming relationships and problems communicating. There is no cure for autism but that does not stop some healthcare professionals from claiming it is caused by heavy metal poisoning, digestive issues and metabolic problems that can be treated with expensive and unproven treatments.

"A number of these speakers are opportunists and predators who prey on the fears and the desperation of parents who have kids with autism," said Dr. Peter Hotez, a pediatrician at Baylor College of Medicine in Houston whose daughter has autism. "I understand how desperate and hopeless a parent can feel having a child with autism and it doesn't get better with age because now we're dealing with a young adult with autism."

Studies show one third to 43 percent of families pay for sometimes costly and often unproven alternative treatments for children with autism.

Hotez is concerned that the autism summit is using high-profile speakers to sell false hope to parents like him. "These speakers are offering every type of flim-flam therapy you can imagine, from hyperbaric oxygen therapy to chelation. There's one guy who says he can cure autism by infecting people with parasitic worms," Hotez said.

Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn't feel good and changes - AUTISM. Many such cases! — Donald J. Trump (@realDonaldTrump) March 28, 2014

Fiona O'leary, an autism rights advocate from Ireland who is herself on the autism spectrum, said the summit pretends to be about people living with autism while serving only to promote dangerous myths and medicines.

“What we need to be doing is supporting people with autism and listening to them but we’re not invited because they don’t want to hear from us," said O'leary, who has two children with autism. She cites the summit's lack of autistic speakers as evidence that the words and experiences of those living with the condition are not important to the organizers.

O'leary founded a nonprofit in Ireland, Autistic Rights Together , that campaigns for better regulation of treatments that purport to reverse autism. "We are vulnerable," she said. "Parents are vulnerable, many don't have support and they're being fed misinformation by charities like Generation Rescue."

O'leary said she was threatened by a doctor who prescribes a quack medicine known as the Miracle Mineral Solution when she spoke about the dangers of the treatment. "They don't care about people with autism," she said. "They threaten people with autism who dare to speak up."

Dangerous treatments, meaningless tests

The autism summit features a training session on hyperbaric oxygen therapy although the website is careful not to say that it is a treatment for autism. Instead, the website notes that hyperbaric therapy has been “clinically demonstrated to provide symptomatic relief and increase quality of life for patients suffering from several chronic and acute conditions.”

The Food and Drug Administration warns against using products that claim to reverse autism. These include:

Hyperbaric oxygen therapy: this involves inhaling oxygen inside a pressurized chamber. It is approved by the FDA for treating decompression sickness in scuba divers but is not approved for treating autism. One flawed study claimed the treatment is effective while numerous studies have shown it does not treat autism.

Clay bath powders: these claim to detoxify the body by drawing out heavy metals and chemical toxins. The FDA has found manufacturers claiming these clay baths offer "dramatic improvement" for symptoms of autism. They don't.

Miracle Mineral Solution: it's really not wise to make children drink bleach (I never thought I'd have to say that), which is what Miracle Mineral Solution is. Also referred to as MMS, its sellers would like you to believe it when they tell you on their website that MMS is "The answer to AIDS, hepatitis A, B and C, malaria, herpes, TB, most cancer and many more of mankind's worst diseases." The FDA has received reports of people who have suffered severe vomiting and life-threatening low blood pressure after drinking this solution.

Probiotics: the FDA has found companies peddling these products claiming they treat autism. The agency says probiotic products "have not been proven safe and effective for these advertised uses."

Besides useless and sometimes dangerous treatments, doctors prey on parents of children with autism by using meaningless diagnostic tests. To “prove” to parents that their child has heavy metal poisoning, urine is tested for metals after the child is given a chelation treatment. The problem with these tests is that the healthy human body contains trace amounts of metals and there’s no standard reference range of how much should come out in a person’s urine after they’ve taken a chelation treatment.

But labs that collude with some doctors send back alarming results that appear to show high levels of metal in the child’s urine. These are contrasted with a so-called reference range taken from a person who has not been given chelation treatment.

The American College of Medical Toxicology has said chelation treatment does not improve symptoms of autism and that "provoked" or "challenge" tests of urine are not reliable means to diagnose metal poisoning and have been associated with harm."

Anti-vaccine, anti-science

While promoting treatments that are dangerous and ineffective, a number of speakers at the summit are asking parents to forgo an intervention proven to save lives: vaccines. “Some of them are virulent antivaxxers,” said Hotez, who is in the unique position of being a father of a child with autism and working as a vaccine researcher.

McCarthy, whose organization is hosting the autism summit, has claimed her son's autism was caused by vaccines. She later backtracked on her anti-vaccine stance but continues to advocate for spacing out vaccinations, a dangerous strategy known to increase a child's likelihood of falling sick and sparking disease outbreaks. The CDC vaccination schedule is based on science and reams of data show it is the safest, most effective way to prevent children from infections.

Study after study has proven that vaccines do not cause autism. Even a study funded by an anti-vaccination group found that vaccines are safe. But fraudulent medical research and celebrities such as McCarthy and Jim Carrey who say that vaccines cause autism have had an impact. There has been an increase in outbreaks of measles, whooping cough and mumps in the U.S.

One speaker at the summit is a anti-vaccine TV producer who has likened people with autism to dogs. "I would think when you have a child with autism or on the spectrum, you have no reference point. I don't want this to sound wrong but it's a little bit more like having a dog or a Doberman or something that you don't understand how it thinks," says Del Bigtree in a YouTube video before adding, "This is not sounding right."

Bigtree produced the anti-vaccine film, Vaxxed, which was pulled from the Tribeca Film Festival earlier this year. O'leary posted a Facebook video criticizing the film and the anti-vaccine movement. Two days later she was sent a cease and desist letter from the film's distributor.Cinema Libre Studios asked her to stop "making any statement to any person with regard to the film," and the filmmakers, Andrew Wakefield, Polly Tommey and Bigtree.

Wakefield is the British doctor who lost his license to practice medicine after performing unethical experiments on 12 children and making up data to show a non-existent link between the MMR vaccine and autism. He now lives in Austin.

"These people are terrifying autistic people and terrifying parents," said O'leary. "It's not just a movement against the MMR vaccine, it's against all vaccines, against doctors and the government. They want us to stop vaccinating our children."

Protecting your family

The onus is on families to protect themselves from health care workers and business people peddling expensive treatments and false hope. While the FDA is cracking down on fraudulent treatments, the agency does not keep up with the myriad miracle cures that purport to reverse autism.

Here's how the FDA suggests you avoid fraudulent claims:

Be suspicious of products that claim to treat a wide range of diseases.

Personal testimonials are not a substitute for scientific evidence.

Few diseases or conditions can be treated quickly so be suspicious of any therapy claimed as a "quick fix."

So-called "miracle cures," which claim scientific breakthroughs and secret ingredients, may be a hoax.

Debunked is your go-to site for demystifying science and medicine. Send your questions and conspiracy theories to syasmin@dallasnews.com or tweet me @DoctorYasmin. I'm a medical writer at the Dallas Morning News and a professor at the University of Texas at Dallas. I worked as a medical doctor and disease detective before training as a journalist.

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