Stem cell transplant cures children with sickle cell anemia, says Alberta hospital

7 girls, 2 boys cured in what lead doctor considers unprecedented treatment

By Lisa Monforton,

Cardelia Fox has a tattoo on the inside of her right forearm with the words "Set free." 

It's a reminder of how a cutting-edge transplant at the Alberta Children's Hospital cured her of sickle cell anemia and a life of hospital stays and blood transfusions.

The chronic genetic blood disorder caused Fox to have three childhood strokes — the first when she was only six months old. She would have two more at age six and 10.

Until the age of 17, she had been in and out of hospital and previously needed to have monthly life-saving blood transfusions.

The year Fox turned 17 she was one of the first patients to undergo the stem cell transplant procedure at the Alberta Children's Hospital.

The success of the procedure has captured interest from around the world, says Dr. Greg Guilcher, a pediatric oncologist who leads the sickle cell blood and marrow transplant program in Calgary.

Dr. Greg Guilcher is the lead doctor for the stem cell transplant procedure at Alberta Children's Hospital.

"To our knowledge, no one else is offering this protocol in children with sickle cell anemia," said Guilcher, who is also an assistant professor in the departments of oncology and pediatrics at the University of Calgary's Cumming School of Medicine.

What sets the Calgary procedure apart from other sickle cell anemia cures in young children is the lead up to the transplant. 

"​This protocol uses the 'lightest' doses of medication — no chemotherapy but immune suppressing drugs only, with a low dose of radiation," said Dr. Guilcher in a statement. 

While the protocol was developed and is used in the U.S., Dr. Guilcher said he's not aware of any other hospital using it on children.

More exciting is the fact that there have been no incidents of stem cell rejection. 

"We're getting phone calls and emails from around the world from interested parents and other doctors. We think we're ahead of the curve in offering this curative therapy as a standard of care."

Sickle cell anemia is a chronic illness where blood vessels can become blocked when blood cells change into a sickle shape, potentially affecting every organ and causing strokes, lung disease heart strain and spleen and bone damage. With advanced drug therapy treatment, life expectancy is 55- to 60-years-old.

The success of the procedure, which was first performed in Calgary in 2009, has cured seven girls and two boys to date.

Life-changing, says patient

"Before the stem cell transplant I felt like I was trapped," says Fox, whose sister Tamika Allen was a perfect match — a rare one in five occurrence within families. "Without this treatment I would likely still be at Foothills getting blood transfusions every month."

Tamika Allen, left, was a perfect stem cell match to her sister Cardelia Fox, which allowed her to have a procedure curing her of sickle cell anemia. (CBC)

Once Allen found out she was a full match, she didn't think twice about helping her sister.

Without a family match, the transplant procedure is generally considered too risky to perform.

"When we learned I was a match there was never any question of whether or not I'd do it," said Tamika, now 22. "Of course I'm going to do this for my sister. It was such a good feeling to be able to help make her life better — now I call her my mini-me."

Rising incidence in Canada

People of African descent are most often affected by sickle cell anemia. One parent can pass on the mutation and not cause the illness, but the illness results when both parents pass it on.

Fox's grandmother died at the age of 35 because of complications from the disease.

In 2008, the Sickle Cell Clinic at the children's hospital regularly treated 16 children.

Now there are more than 80, primarily because of immigration, says Dr. Mike Leaker. He is the head of the clinic, which sees patients from Alberta, Saskatchewan and eastern B.C.

"We now have some excellent medications that can change the course of the illness for many patients," said Leaker. "But a drug is still a treatment, not a cure. For families the word 'cure' is incredibly powerful."

Guilcher is expecting continued interest in the procedure from around the world

Sickle Cell Anemia: From Basic Science to Clinical Practice