Jett and John Travolta.

Voxant Newsroom/CWS30

OFFICIALS in the Bahamas have conducted an autopsy on Jett Travolta, the teenage son of actor John Travolta and his wife Kelly Preston, who died last week during a family holiday, police said.

The results to find how 16-year-old Jett Travolta died could be made public as early as Monday afternoon local time, the Nassau police told AFP.

Jett was last seen on New Year's Day when he went to use the bathroom at the family's residence at the Old Bahama Bay Resort on Grand Bahama island, a statement issued on Sunday by the Bahamas' police Chief Superintendent Basil Rahming said.

"He was discovered in the bathroom in an unconscious state around 10am" the next day by a caretaker, the statement said.

Jett Travolta had a history of seizures since he was a toddler, and a lawyer for his father said he may have suffered a lethal one on Friday.

The youth was the only son of Travolta, 54, and actress Preston, 46. The couple also has an eight-year-old daughter, Ella.

Hours before the autopsy was conducted, the teen's grieving family issued a statement about the loss of their son and brother.

"Jett was the most wonderful son that two parents could ever ask for and lit up the lives of everyone he encountered. We are heartbroken that our time with him was so brief," the family said in a statement on Sunday.

"We have received many messages of condolence from around the world and we want to thank everyone for their prayers and support. It has meant so much to us," the statement said, signed: "With love, John, Kelly and Ella."

Jett Travolta is due to be buried in Ocala, Florida, where his family lives.

The youngster's life was complicated by health woes from a young age.

His mother, who like her husband is a member of the Church of Scientology, had "credited a detoxification program based on the writings of Scientology founder L Ron Hubbard with helping to improve Jett's health", according to People Magazine.

His father has denied reports that his son was autistic, but said that at age two, Jett had Kawasaki Syndrome, a condition that can lead to heart disease, US media reported.

A vascular illness in which the blood vessels are inflamed, Kawasaki Syndrome occurs almost exclusively in infants and toddlers, Robert Baltimore, a professor in paediatrics at Yale University's school of medicine, told AFP.

But the illness, the cause of which is not known, does not usually result in seizures, does not continue for many years, and rarely recurs, said Baltimore, who is a specialist in Kawasaki Syndrome.

Treatments given Jett Travolta, as reported by US media, "are not part of what I would call conventional treatment for Kawasaki disease", he said.

No information was available about the type of treatment Jett Travolta received when he was diagnosed with Kawasaki Syndrome or for his seizures.

A Church of Scientology spokeswoman told AFP the church has no teachings on what medical care members should seek and "absolutely does not prevent people from seeking medical treatment".

"Scientologists go to medical doctors, use prescription drugs, take painkillers, have surgery when they need it," spokeswoman Karin Pouw said.

Raised in Englewood, New Jersey, John Travolta is famous for roles on television and in films such as Grease, Pulp Fiction (1994) and True Colours (1991).

He received Academy Award nominations for the disco epic Saturday Night Fever (1977) and Pulp Fiction.