The first Canadian patient to receive an experimental transplant of liver cells in Alberta two years ago is now a healthy toddler, her doctors say.

Nazdana Jan, of Winnipeg, received her transplant in November 2012 when she was two months old from a team at the Alberta Children's Hospital in Calgary in an effort to help keep her alive long enough to receive a full liver transplant.

In April, she successfully underwent a liver transplant in Toronto.

Nazdana and the four other infants who received the therapy all have urea cycle disorders, a genetic disease that causes ammonia to build up in the body and can lead to brain damage and death.

Most newborns with the disorder die within the first two weeks of life without treatment.

"The therapy is designed to buy time until infants have grown enough to improve the chances of success with a solid organ liver transplant. It's a bridge therapy until a donor organ can be found," said Dr. Aneal Khan, the medical geneticist leading the team behind the therapy.

"Of the five cases to date, two have successfully made it to liver transplant, two are progressing well and one has died from an infection unrelated to the treatment."

Ammonia is naturally produced as the body uses protein. But for those with urea cycle disorders, the process of converting ammonia into urea — the harmless substance that gives urine its yellow colour — does not work properly because of a gene abnormality.

The condition is incurable and very rare. Only about 50 babies are born each year in Canada with the condition.

Research still ongoing into therapy

Of the five patients who underwent the experimental therapy in 2012, four did so as part of a research trial sponsored by a biotechnology firm and one received the liver cells on compassionate grounds.

The therapy works by transforming liver cells from donor organs that would otherwise go to waste into cells that can be transplanted.

Nazdana's procedure took place over six days, with each liver cell infusion taking about an hour.

While research into the therapy is still ongoing, doctors say it has allowed them to get better control of ammonia levels in the body.

Nazdana's father, Jouhar Ali, has nothing but thanks for the care his daughter has received.

"The liver cell transplant in Calgary gave a new life to Nazdana and hope to my family that she will have a healthy future," he said. "I am really grateful and appreciate all the doctors and nurses, including the social workers, for their help and support."