At 34 years old, Katelyn has been a patient at Children’s Hospital of Philadelphia (CHOP) nearly her whole life and probably always will be. 

When she was barely one, Katelyn experienced a seizure that sent her to the emergency department at a local hospital. She was treated and cleared to return home but continued to experience low blood sugar symptoms that had been misdiagnosed.   

These symptoms weren’t completely unfamiliar to Katelyn’s parents. Years before, her father had been diagnosed with congenital hyperinsulinism (HI). Congenital HI is a rare genetic disorder that causes the pancreas to create too much insulin, leading to consistent low blood sugar. Because the brain requires a constant supply of sugar, low levels in the blood can be dangerous and if left untreated, can lead to seizures, brain damage and possibly death.  

“My parents knew something wasn’t right,” said Katelyn. “They trusted their instincts and took me to CHOP for further evaluation.”

Shortly following comprehensive testing at CHOP, Katelyn had the proper diagnosis and treatment plan her family had been looking for. She was diagnosed with HI, just like her father. They were both found to have a form of HI called GDH-HI. This particular type causes low blood glucose (hypoglycemia) due to excessive insulin secretion that occurs during fasting or after protein consumption and can elevate ammonia levels in the blood.

GDH-HI was first discovered by researchers and clinicians at CHOP. It’s caused by a genetic mutation passed down from parent to child. So, when Katelyn’s younger sister was also diagnosed shortly after birth, the family wasn’t caught off guard. Together, they were among the first patients identified with this type of congenital HI.

The start of a lifelong relationship with CHOP

Once her journey with CHOP began, Katelyn’s care continued for decades. In recent years, it’s been managed by Diva D. De León-Crutchlow, MD, MSCE, Chief of the Division of Endocrinology and Diabetes and Director of the Congenital Hyperinsulinism Center, the largest specialty care program of its kind in the world. 

For over 50 years, CHOP has treated more than 1,900 patients with HI through a comprehensive support model that includes multidisciplinary care, education, genetic counseling, psychosocial support and long-term follow-up.

Because HI often requires lifelong and highly specialized treatment, CHOP doesn’t just care for kids, they also care for adults. In Katelyn’s case, the continuity of care throughout her adulthood has been key in keeping her blood sugar levels stable.

Over time, Katelyn learned how to live with HI. For her, it was all about being prepared. Growing up, it was normal for her to carry extra snacks or juice boxes — just in case. When Katelyn eventually became pregnant with her son, Liam, she knew how to prepare for the possibility that he too could be diagnosed with HI.  

Coordinated care for mother and baby   

Throughout her pregnancy, Katelyn worked closely with Dr. De León-Crutchlow to carefully monitor and adjust her treatment plan, ensuring the safest path was taken to protect her growing baby.   

“Managing my condition was a delicate balance during my pregnancy,” said Katelyn. “Dr. De León-Crutchlow and her team were incredibly attentive throughout that entire process.”  

When Liam was born with low blood sugar levels, he was transferred to the NICU at the local hospital where Katelyn delivered him. She was wary, but she wasn’t scared — she and the CHOP team had prepared for this.   

Once Liam’s blood sugar levels were stabilized by local care teams, CHOP quickly coordinated with them to have Liam transported to CHOP’s Philadelphia Campus, where he was urgently placed in the care of Dr. De León-Crutchlow and her team.   

“When CHOP’s transport team arrived to take Liam, I finally felt reassured knowing he would be receiving the highest level of care,” said Katelyn.

At CHOP, Liam underwent comprehensive testing that confirmed what Katelyn had been suspecting: Liam also had GDH-HI. Familiar with the treatment regimen Liam was now receiving, Katelyn was relieved when his blood sugar levels became stable. “It was incredible to see how quickly he stabilized with the appropriate treatment,” said Katelyn.   

Reflecting on expert care and compassionate support

Today, both Katelyn and Liam’s HI continues to be well-managed, and their blood sugar levels remain stable. Together, they receive ongoing care at CHOP. Now part of her new routine, Katelyn takes Liam along for appointments that are conveniently scheduled at the same time.   

“Our experience working with the care team at CHOP has been exceptional,” said Katelyn. “Their collaboration, communication and expertise have played a significant role in helping us navigate both diagnosis and ongoing management with confidence. I’ve always felt truly supported in my own care, and it means so much to know that my son is receiving that same level of dedication and expertise.”  

Passing on lessons of resilience and preparedness  

Managing HI has always been part of Katelyn’s story, but she makes it clear that it isn’t her whole story. She’s never let HI hold her back.  

“I graduated from college and now work as a special education teacher in our local public school district, which is a career I am incredibly proud of,” she said. “Living with HI has certainly required awareness and management, but it hasn’t prevented me from building the life I envisioned.”  

She attributes her unwavering outlook to the way she was raised. “My parents never allowed HI to define who I am,” said Katelyn. “And because of that, I have always viewed it as something I manage, not something that limits me.”    

Katelyn plans to pass on the same perspective through her own parenting, committed to teaching Liam that he’s capable of achieving great things, with or without HI. And she wants other patients and families to do the same.     

“Your child is full of strength, curiosity, and so many other amazing qualities that shine far brighter than their diagnosis,” said Katelyn. “With support, guidance and patience, you’ll find that HI is something you manage, not something that limits you or your child. You can still dream big, achieve big and live fully — you might just need a snack or a juice along the way.”