A 10-month-old Louisiana boy born without natural immunity to disease may survive to adulthood because of the transplantation of a tiny liver from an aborted fetus.

The operation, performed here Aug. 20, was the first of its kind in Louisiana and the 10th in the United States since such surgery began in 1975, said Dr. Sami L. Bahna, who conducted the procedure. He is an assistant professor of pediatrics at Louisiana State University School of Medicine.

Blond, blue-eyed Henry Leckett was brought here from his southwest Louisiana home after three months of treatment failed to cure a fungus infection on his skin and in his mouth. By the time he arrived at Charity Hospital here, the child had also developed pneumonia in both lungs, said Bahna.

Doctors suspected his immune system was inactive, because the strong medication he was receiving, designed to trigger the body's own infection-fighting antibodies, was having no effect, said Bahna, who also is director of allergy and immunology at LSU Medical Center and Charity Hospital.

Henry was found to have severe combined immune deficiency, a rare congenital disease that prevents a victim's body from fighting germs and infection. It is called "combined," Bahna said, because a person suffering from the disease lacks both antibodies and cells to ward off illness and infection.

Without treatment, an infant victim dies by his second birthday, Bahna said, because the immunity he receives from his mother wears off by then.

Generally, bone marrow transplants from a brother or sister or other relative with the same blood type can build up a victim's immune system, but Bahna rejected this method for several reasons: Henry is an only child, neither of his parents and none of his other relatives matched his blood type, and even if one of them did, the transplanted bone-marrow cells could well be strong enough to kill the weakened boy.

The cells found in bone marrow develop in the liver, so Bahna thought of giving Henry a transplant fetal liver. "The younger the fetus, the better the chances of survival, and the better the chance the cells will live peacefully in a young body," he said.

After getting the approval of the hospital's review board, Bahna sent letters to obstetricians in the New Orleans area, asking them to tell him when they had a patient who wanted an abortion and might be willing to donate the fetus' liver.

Bahna had to wait two months for a reply.

In such a transplant, speed is vital; Bahna had 90 minutes. For maximum efficiency, the two -- the abortion and the transplant -- were conducted in adjoining rooms at Charity Hospital. Using magnifying glasses, Bahna found and removed the tiny liver -- about one-fifth of an inch long -- from the eight-week-old embryro and used a catheter to put it into Henry's abdomen. The procedure took only 30 minutes.

The fetal liver was allowed to "float" in the abdominal cavity, where it's expected to produce antibodies and infection-fighting cells. Within a few weeks, Bahna said, these should begin to show up in Henry's blood.

Since the operation, Henry has lived in a double-sealed isolation room in Charity's Pediatric Intensive Care Unit. To get into his room, visitors first enter an antechamber, where they don surgical gowns, caps and gloves to keep from contaminating the infant.

They then pass into his glass-walled room, where Henry's bed is littered with stuffed toys. A television set plays in one corner. His parents, who have returned to Henry's home town of Acadia, visit once a week.

The environment is designed to assure Henry's normal psychological development, Bahna said.

The doctor will not say what Henry's chances for survival are, but he said that if the child progresses satisfactorily, he should be able to go home and live a normal life without a protective "bubble" in which other children without natural immunity have sometimes been housed.

"I don't expect to see another child like him for 10 years or more," said Bahna.