July 16, 2013 -- A man who awoke in the emergency room at Desert Regional Medical Center in Palm Springs, Calif., last February speaking only Swedish and suffering from a case of global transient amnesia, has a sister living in Louisiana who is stunned by the fate of her long-lost brother.

The hospital has identified the patient as 61-year-old Michael Thomas Boatwright and says that he has been told he has a sister, Michelle Brewer, 59, of Kentwood, La.

"She hasn't talked to him in over 10 years," Brewer's step-daughter, Shannon Coleman, 36, told ABCNews.com. "She seemed like she was really surprised."

Boatwright, 61, was found unconscious in a Motel 6 and was taken by hospital ambulance to the medical center, according to medical center spokesman Rich Ramhoff.

The only things he had on him were a duffel bag of athletic clothes, a backpack, five tennis rackets, two cell phones, some cash, a set of old photos and four forms of identification, including a Florida license and a veteran's card.

But Boatwright had no memory of who he was or how he got there. He did not speak or understand English and didn't even recognize his own face, according to the Desert Sun, which first reported the story. He told hospital officials his name was Johan Elk.

Brewer said her brother had "just disappeared" and she had no way of getting in touch with him after their mother died last year.

"He's always been a wanderer," she told the Sun. "Then he'd come back when he needed some money or something from somebody. Then he'd take off again."

An investigation into his IDs found that Boatwright was likely a 3-D graphic designer who had worked in China and Japan as an English teacher for a decade. He had flown from Hong Kong to Palm Springs just four days before he was found unconscious. The U.S. Navy veteran, who was raised in Miami, first went to Sweden in 1981.

The Sun tracked down Brewer, but hospital spokesman Ramhoff said the hospital has not yet independently confirmed their relationship. But, he said, Boatwright has "shown an interest in trying to reach out to her."

"We did not find any major trauma on him," he said. "The assumption was the cause [of the amnesia] could have been psychological in nature, but nothing physical was found."

Ramhoff said psychiatrists concurred on the diagnosis of transient global amnesia, a sudden, temporary episode of memory loss that cannot be associated with epilepsy or a stroke, or a general "fugue" state, which can be longer in duration.

For the last five months, Boatwright has been staying at the Desert Regional Medical Center's skilled nursing facility, which reached out to the community and found people who spoke Swedish to help translate.

His social worker, Lisa Hunt-Vasquez, has been trying to locate family and friends by working with the media and making calls to the Veteran's Administration, Florida police and other leads.

"She has spent a lot of time calling China and Sweden to find information, but the language barriers and lack of information ran into dead ends," Ramhoff said.

Media around the world took an interest and stories appeared in the Swedish paper Aftonbladet and in the British press. As a result, the Sun received photos of people who looked like Boatwright.

Internet users in Sweden said they recognized him as an American who moved to Sweden in the 1980s.

Swedish woman Ewa Espling wrote her Facebook page that Boatwright had been her "childhood sweetheart," according to the Sun. Swedish reports said that he had learned to speak "decent" Swedish and played on a Medieval jousting team.

According to the Swedish newspaper Aftonbladet, Espling said Boatwright had, "the most kind eyes [she] had ever seen." But she said he had been haunted by nightmares of the Vietnam War, where he had served.

Boatwright lived on a boat called "Honey Bea" off Rhode Island in 1984, according to the postmarks of letters he sent to Espling. He also spent time in Houston, Mexico and Newport, reports the Sun. He left Sweden for good in 2003.

Today, hospital officials say Boatwright is "doing well" and knows about the possibility of seeing his sister.

"He has expressed that some days he is a little bored and depressed," Ramhoff said. "As far as trying to stay active, he works out at the rehab gym when he can. He certainly is in good physical health. He is handling his problems well and in the last two days he has expressed to me that he has been overwhelmed, but grateful that leads have come in.

"Obviously, he's not at a level where he needs physical medical care anymore," he said.

The hospital is trying to find a home in the community where Boatwright could live.

"We are continuing to work with Social Security and with the Veterans Administration because he definitely has a record," he said. "Ultimately, we hope to have a satisfactory resolution. But we still have to find a satisfactory way to get him out of the hospital."

Ramhoff said he had tried to call Brewer last night, but had been unable to reach her. "She has probably been flooded with calls," he said.