Family discovers 5-year-old son’s life-threatening condition after reading news story

A Texas family is rallying to raise awareness for Sanfilippo syndrome, a rare progressive condition that their son was diagnosed with after his symptoms were initially mistaken for autism.

Valerie Byers sought a second opinion about her 5-year-old son’s developmental delays after reading an online news article about Eliza O’Neill, a 5-year-old girl with Sanfilippo syndrome whom last covered in November.

Glenn and Cara O’Neill, Eliza’s parents, began the Cure Sanfilippo Foundation at the end of 2013 and launched the website to help fund a clinical trial at Nationwide Children’s Hospital in Columbus, Ohio, that would conduct a clinical trial for a gene therapy that may offer a cure for the life-threatening disorder. Eliza has Sanfilippo syndrome-Type A, while Byers’ son, Will, was eventually diagnosed with Sanfilippo syndrome-Type B. According to the National Institutes of Health (NIH), type A is most severe, whereby the enzyme heparin N-salfatase is rendered dysfunctional. Type B occurs when a person doesn’t produce enough alpha-N- acetylglucosaminidas.

All types of the genetic condition occur when the enzymes needed to break down sugar molecules are missing or defective. It is marked by developmental delays, deteriorated mental status, and a final height that is below average. Life expectancy for the disorder varies, but most patients live only to their teenage years, while others die younger and some live to be older, according to the NIH. Sanfilippo syndrome is inherited as an autosomal recessive trait.

A chance encounter

Byers asked for a blood and urine test for her son in February after seeing a video the O’Neills distributed that told of Eliza’s journey with Sanfilippo syndrome. Byers’ background is in psychology, and she said she never saw autism symptoms in Will.

“In February, I randomly chanced across a news article about Eliza, and as soon as I saw her video, my heart dropped,” Byers, 33, told “I recognized Will in this diagnosis.”

While friends cautioned against diagnosing Will from the Internet, she said her gut compelled her to discuss the concerns with her pediatrician and get Will tested for Sanfilippo. A urine test a week later showed he had mucopolysaccharidoses (MPS) and a following blood test indicated he tested positive for Sanfilippo syndrome-Type B.  According to the NIH, Sanfilippo syndrome is the most common type of MPS, a group of diseases seen in 1 in about 70,000 births.

“I was completely devastated,” Byers said. “To know that your child has a terminal disorder and that there’s no treatment … you don’t even want to get out of bed in the morning.”

Byers and her husband, Tim, contacted Glenn and Cara O’Neill, who referred them to a Sanfilippo syndrome-Type B clinical trial being conducted at the University of Minnesota. The clinical trial, which marks the first-ever enzyme replacement test in humans, began in January and was originally supposed to have only nine study participants. When researchers increased the number of spots to 11, Will got the final spot. This week, doctors implanted a port in his chest, and they will administer the enzyme every two weeks for the next six months.

“It is only because of us seeing Eliza’s story and the O’Neills’ dedication to raising awareness that we got Will enrolled in this first-ever enzyme trial,” Byers said. “It is still experimental; we don’t know if it will work. We’re just happy that he has a chance.”

Joining the fight

The Byers family— which also includes 19-month-old Samantha— is also working to raise funds for the same gene therapy trial that the O’Neills are seeking for Eliza. The clinical trial, sponsored by Abeona Therapeutics, would have separate portions for types A and B of the disorder.

The Byers began the “5 for 5 Challenge” on May 11, 2015 to encourage donors to contribute dollar amounts ending in the number five. Their goal was to raise $25,000 in one month, but in just 52 hours the fund climbed to $50,000, Byers said. All money raised through the effort goes to the O’Neills’ Cure Sanfilippo Foundation. Byers said that trial serves as a backup plan in case the experimental enzyme-replacement trial does not prove successful.

“The struggle with Sanfilippo is there’s a lot of the cell waste from the disorder in the brain, and the problem with treating it in the past is they can’t get the enzymes past the blood brain barrier. We’re waiting to see if this trial has figured it out,” Byers said.

The Byers are also waiting for the results of a blood test for Samantha, who has a 25 percent chance of being affected by the syndrome, a 25 percent chance of being unaffected, and a 50 percent chance of being a carrier of autosomal recessive trait, like Tim and Valerie.

“She has a normal urine test, so we’re cautiously optimistic,” Byers said.

On the day Byers talked to, it was the end of the “5 for 5 Challenge,” which also marks Will’s fifth birthday. They were headed to Will’s favorite restaurant, Jason’s Deli, near their Spring, Tex., home, which was hosting a spirit night in his honor, promising to donate 15 percent of their proceeds to the Cure Sanfilippo Foundation.

“We just really want to have our story out there because there could be another family out there struggling with a misdiagnosis,” Byers said. “Life is too short with Sanfilippo.”