Doctors today performed an autopsy on Jett Travolta, the 16-year-old son of actors John Travolta and Kelly Preston, who died Friday. The results were not immediately released, but family attorney Michael Ossi told TMZ that the teen died after suffering a seizure and hitting his head on a bathtub or toilet seat in the family's home in the Bahamas, where they were spending the holidays. 

Preston said six years ago that Jett became very ill at age two and was diagnosed with Kawasaki syndrome, a rare inflammatory condition most common in young children. She and Travolta blamed Kawasaki syndrome for what they described as Jett's developmental disabilities, according to CNN.

In 2007, restaurant manager Tim Kenny, the parent of an autistic child, charged on the entertainment news site that Jett was autistic but was not being treated for problems associated with the disorder. The Travolta family had maintained that the teen did not suffer from autism and, after the item appeared, attorney Marty Singer told the New York Post that Travolta and Preston "have [taken] and they continue to take the best possible care of their children. To suggest anything to the contrary is very hurtful to a loving family and also would be false and defamatory."

Ossi told TMZ that Jett had been taking meds to control seizures.

Kawaski syndrome is most common in Japan, according to the Centers for Disease Control and Prevention (CDC) and is 1.5 times more common in boys, a University of California, San Diego historical review of the disease notes. In the continental U.S., it affects nine to 19 in 100,000 children, 85 percent of them younger than five years old, the CDC says.

We asked Walter Molofsky, chief of pediatric neurology at Beth Israel Medical Center in New York, about Kawasaki syndrome and its possible role in Jett Travolta's death. An edited transcript of our conversation follows.

What is Kawasaki syndrome?
It first presented in the late 1960s and early 1970s in Japan, with the first case studies published in 1974. It's an inflammatory, autoimmune disorder (in which the immune system attacks healthy tissue in the body), but we're not quite clear of the cause. It could be a specific reaction to a virus or some sort of infectious agent, but none has been identified. However, it has some features consistent with an infectious cause: It occurs mostly in winter and spring, it's usually among toddlers and rarely in children under three months or in adults.

What are the symptoms?
A high fever above 101 for more than five days, severe redness in the eyes, a rash on the stomach and chest, red, cracked, dry lips, swollen tongue, sore throat and swollen lymph nodes.

How often does Kawasaki syndrome cause serious health problems? Are seizures among them? What about autism and other developmental disabilities?

The main, long-term side effects are cardiac problems, such as aortic aneurysms (a bulge in the blood vessel leading away from the heart that is dangerous, because it may burst, spilling blood and potentially causing hemorrhaging), cardiac arrythmias (irregular heartbeats), inflammatory disease of the heart and abnormalities in the heart valves. Twenty to 25 percent of patients develop a coronary artery aneurysm afterwards. The mean age at presentation for cardiac damage is 24, plus or minus 8 years. It's recommended that Kawasaki patients be followed for 10 or 20 years.

Seizures are very uncommon. Maybe during the acute episode during a high fever; fevers themselves can cause seizures sometimes. But Kawasaki syndrome is rarely a cause of encephalitis (swelling of the brain) or residual brain problems. I'm sure there are exceptions to the rule, but I can't speak to that.

Kawasaki syndrome is not believed to be one of the etiologies of autism. Autism is a congenital, neuro-developmental disorder, which means you are born with it. It emerges between ages one and three. Because it starts during early infancy and because these children can look normal initially, a whole host of things have been attributed to causing autism: vaccines, infections, lead and other toxins. And because we can't point to a cause of autism, there's an impression that these temporally related issues must have caused it.

What happened in this case is that, unfortunately, this child probably had an episode of Kawasaki disease and, because it occurs between ages one and three, that was a time they noted neuro-developmental disorders, and seizures are more common in autistic children. I never heard of Kawasaki syndrome as a cause of autism till I read about Jett Travolta [allegedly having the disorder].

What is the treatment for Kawasaki?
The main treatments are to prevent cardiac disease. Patients are usually put on IV gamma globulin, a mixture of antibody proteins that fights inflammation and help fight infection by boosting the immune system, for a week to 10 days, and usually put on aspirin, to prevent inflammation, for years.

While aspirin has been linked to Reyes syndrome (a potentially fatal condition that can cause brain and liver damage) in young children, there's a risk-benefit ratio. If you have a reason, that would outweigh any potential risks. Aspirin has a specific inflammatory effect that's different from ibuprofen. It has anti-platelet function and is used for stroke prevention, as well. Ibuprofen doesn’t have those properties.

Most children recover, are put on aspirin and are followed for years to make sure they're stable. And that's it. The main problem is follow-up for cardiac disease.

How often is it fatal?
Rarely. Most children tend to recover. Death may occur if the cardiac complication is unrecognized.