Transplant gives toddler with rare condition a second chance

By Maureen Gilmer, Riley Children’s Health senior writer, mgilmer1@iuhealth.org

Michelle Duff describes her son, Jack, as “a very happy little man, a bubbly little guy.”

He is both those things and more. He’s a busy baby who creeps and crawls and stands and falls, just like babies do as they explore the world around them.

But Jack, 16 months old, is trying to catch up after he was diagnosed with a rare condition called MPS 1, caused by a missing enzyme and characterized by an abnormal build-up of toxic materials in the body’s cells.

Jack was the first baby in the state diagnosed on newborn screening since Indiana’s screenings expanded in 2020 to include MPS 1 and other conditions.

His mom had never heard of it, but she and Jack’s father, Jacob Orshovsky, unknowingly carried the gene that causes the disorder and passed it on to their son.

Jack’s twin, Jackie, is not affected; neither is the couple’s older daughter, JoJo.

“Both girls would have had a 25% chance of having the condition,” according to Katie Sapp, metabolic genetic counselor with Riley Children’s Health, explaining that even though Jack has a twin, she is obviously not identical, so she was at no greater risk for having the gene mutation than her older sister.

It’s a surprise diagnosis for sure, for Jack’s parents, she said.

“It’s completely out of left field. People have never heard of it.”

MPS 1 is also known as Hurler syndrome, named for the doctor who first described a child with the condition in 1919.

Duff remembers getting the results of that screening when Jack was about 2 weeks old.

“He looked like a normal baby to me. I didn’t think anything was wrong until I got that call,” the Evansville resident said.

She brought Jack up to Riley the very next day, and specialists did more testing and walked her through what to expect in the months to come, including what treatments were available to slow the progression of the disease.

While babies with MPS 1 typically have no signs or symptoms at birth, those with the severe form – the kind Jack has – usually start exhibiting symptoms within the first year. Those can include skeletal and spinal deformities, developmental delays, hearing and vision loss and enlarged organs.

When her son was about 2 months old, Duff said she started seeing issues with his spine and rib cage.

“I was traumatized when it started showing up,” she said.

Not long after that, Jack began receiving weekly enzyme infusions to replace the enzyme that his body lacked, which helps break down toxins.

But in mid-August, Jack underwent a bone marrow transplant at Riley with his older sister as his donor. Dr. Miriam Kim, who specializes in pediatric hematology and oncology, performed the transplant, the first at Riley in several years to treat what Sapp says are classified as “storage disorders.”

After weathering a few complications, which included a stay in the PICU with respiratory problems and graft vs. host disease, he marked his 100 days post-transplant in late November and is recovering nicely, Sapp and Dr. Kim said.

His enzyme levels were in the normal range at around the 100-day mark, said Dr. Kim, adding that having Jack’s sister be such a close match made things easier.

The goal of transplant for this condition is to prevent the neurologic symptoms that can come with this diagnosis, Sapp explained.

Those can include developmental delays, intellectual disabilities and behavior issues.

“The transplant doesn’t fix any damage done prior to transplant and is not a cure, but it can prevent any further progression,” Dr. Kim said. “The most benefits for Jack will be from a neurologic perspective. He may have joint and corneal problems, but we are monitoring these. The hope is he will have continued development and will meet his growth milestones.”

Transplant doesn’t completely remove the risk for some of the orthopedic issues, cardiac concerns, hearing loss, etc., associated with the severe form of the condition, Sapp said, “but those are more manageable when you’ve preserved neurologic function.”

Jack and his mom stayed close to Riley during those three-plus months after transplant, spending time at the Ronald McDonald House in between appointments, then going home on weekends.

Today, Jack continues to do well, said his mom, glad to be reunited with the rest of her family back home in Evansville.

“It was hard to be away,” she said. “I cried so many tears. I missed them to the high heavens.”

But her little guy is filling their home with laughter and love.

“He just learned how to blow kisses. He has a goofy little personality, and he flirts with all the girls,” she said.

He is also doing better standing up on his own, a challenge due to some of the joint issues common with the condition.

MPS 1 is estimated to occur in one in every 100,000 live births, though Sapp said Jack is the only child diagnosed in Indiana since the condition was added to the newborn screening list in 2020. One other child was diagnosed with a milder form of the disorder. (There are roughly 80,000 babies born in the state each year.)

Jack will continue to be seen by the metabolics and transplant teams at Riley long-term, as well as cardiology, ophthalmology and pulmonology, but his future is brighter, thanks to early diagnosis and intervention, Sapp said.

“We are thrilled with how well Jack’s done and excited that newborn screening has really given us an opportunity to address this early.”

Having the expertise of Dr. Kim, who joined Riley in 2020 from the University of Minnesota Medical Center, is a gamechanger, Sapp added.

“The Riley team has incredible experience doing transplants for other conditions, but storage disorders are a rare bird. They come with rare issues, so when Dr. Kim arrived, we were really excited to have someone with that experience who can share it with the team.”

Photos by Mike Dickbernd, IU Health visual journalist, mdickbernd@iuhealth.org