NEW YORK (Reuters) - A New York man whose wheelchair-bound, morbidly obese wife died last year after she was denied a spot on three different flights home from Europe sued the airlines on Monday for $6 million.

Vilma Soltesz, who at the time was reported to have weighed 425 pounds (193 kg), had an amputated leg and suffered from diabetes and kidney disease, news media said.

She was found dead at her vacation home in Hungary in October after several aircraft crews repeatedly failed to accommodate her size despite telling her they could do so, according to a lawsuit filed in federal court in Manhattan.

The lawsuit accused the three airlines of wrongful death and gross negligence.

The couple left their Bronx home in September on a Delta Air Lines plane, securing two seats for Vilma and one for her husband Janos, and arrived safely in Budapest on a vacation, according to the lawsuit.

By October 2, Vilma Soltesz sought treatment at a hospital in Hungary when she fell ill, according to the lawsuit. She was released and told she could fly home but to see her doctor immediately upon her arrival, according to the lawsuit.

The pair tried to leave Budapest two weeks later on a KLM Royal Dutch Airlines flight, with accommodations similar to what they received on their flight from the United States, according to the suit. But a captain told them to disembark after Vilma Soltesz struggled to maneuver from her wheelchair into her assigned seats, the lawsuit says.

After waiting in a Budapest airport for more than five hours, the couple drove to Prague to catch a Delta flight they were assured could accommodate them. But Delta did not have an adequate wheelchair to transport Vilma Soltesz to her seat, the suit added.

"The Delta flight coordinator told Janos and Vilma that Delta 'did not have access to a skylift' to get Vilma onto the aircraft from the rear, and that there was nothing more Delta could do for them," the lawsuit stated.

Later, on October 22, as several medics and firefighters helped her board a Lufthansa flight, the captain told the couple they had to disembark because "other passengers need to catch a connecting flight and cannot be delayed further," the lawsuit says.

"Exhausted and feeling ill," Vilma Soltesz went to bed after the couple drove back to their vacation home in Veszprem, Hungary, the lawsuit says. On October 24, Janos found her dead, the lawsuit says.

A Delta Air Lines spokesman said the airline had not been served with the lawsuit. Officials with Royal Dutch Airlines and Lufthansa did not immediately respond to a request for comment. An attorney for Soltesz did not immediately return a call seeking comment.

(Reporting By Bernard Vaughan; Editing by Cynthia Johnston and Cynthia Osterman)