MAYWOOD, Ill. (AP) _ A Vietnamese refugee whose brother traveled from their homeland to provide him with a bone marrow transplant died Thursday of a rare blood disorder, hospital officials said.

Vo Tien Duc, 32, died at Loyola University Medical Center of aplastic anemia, said spokesman Rick Romano.

He had received bone marrow from his brother, Vo Hoang Van, 18, on May 13, but his condition worsened May 21 and he slipped into a coma late last week, said Romano.

At the time of the transplant, doctors said Duc was suffering from a number of severe complications, including pulmonary infection and gastrointestinal bleeding. Physicians put his chances for survival after the transplant at only 30 percent or 40 percent.

In a rare instance of medical cooperation between the United States and Vietnam, Van was granted a temporary exit visa and flown to Chicago on April 26 from his home in the Mekong Delta. The two nations do not have formal diplomatic relations.

The transplant was delayed for several weeks because of Duc's poor condition and the need to make extended compatibility tests on the brothers' tissues.

Romano said Thursday that he was where Van was.

Hua Truong, a friend of Duc's who helped finance Van's visit to the United States, could not be reached immediately by telephone at his home or his job.

Dr. Richard Fisher, chief of hematology-oncology at Loyola, called the operation a ''technical success'' immediately after the transplant, but warned it could take as long as four weeks before doctors would be able to determine whether Duc's body was rejecting Van's cells.

Fisher said 11/4 pints of marrow was withdrawn from a large bone in Van's pelvic area and then injected into Duc's circulatory system.

If all had gone well, the marrow cells would have taken root in Duc's bones and begun producing the blood cells his body needed to fight off various infections.