Phenylketonuria (PKU)

Lessons Learned from my Son's Rare Disease Diagnosis

By Kala McWain

Iremember the day we brought our son, Braxton, home from the hospital so clearly. My husband and I were elated to introduce him to his big brother, Remington, and our family felt complete with two happy and healthy boys—until I received a troubling phone call from a nurse at the hospital. Braxton's standard newborn genetic screening test came back positive for phenylketonuria (PKU), a rare genetic metabolic disease. Without intervention, PKU can cause irreversible brain damage and intellectual disability. At only four days old, Braxton's life was flipped upside down and our family was forever changed by this news.

The Textbook Definition

We quickly received a crash course on PKU during Braxton's extended visit with the metabolic clinic at Children's Hospital Colorado. We learned that people with this disease cannot break down phenylalanine (Phe), an amino acid found in many foods including meats, breads, vegetables and cereals. In a newborn, normal Phe levels are ≤ 2 milligrams per deciliter (mg/dL). Braxton's Phe levels were about 29 mg/dL. Phe buildup is toxic and can cause severe neurological damage and neurocognitive defects, leading to an increased risk of seizures, emotional problems, intellectual disabilities and deficits in mental processing and social engagement.

While there are some treatment options available, they present limitations for many patients. As a result, most parents, like us, must try to keep our loved ones living with PKU on a strict, life-long low-protein diet that is extremely challenging to maintain. Given this, new treatment options are desperately needed for many living with this debilitating disease.

Protein Isn't in Everything, but It Feels Like It Is

When Braxton was first diagnosed, we dedicated ourselves to working with a team of metabolic specialists and dieticians to find the right balance of breastmilk and medical formula that would adhere to this strict low-protein diet, minimizing his Phe levels while ensuring he got important nutrients for proper development. As he got older and began to eat solid foods, there was a learning curve for knowing which foods are high in protein and which are not. For example, some fruits and vegetables are safer than others. We must weigh all his food and monitor exactly how much protein he consumes every day. It is exhausting, to say the least. We began ordering low-protein breads, pastas, meat mixes, pancakes, baked goods and cereals from medical food companies to incorporate into his diet.

Braxton is now 2 years old, and I remember spending a fair amount of time crying at the grocery store, staring at the shelves while trying to figure out what I can feed my son when we started solids. Like many toddlers, the foods he is willing to eat are constantly changing. Most of my days are spent thinking about the challenge of feeding him—how to make his meals balanced and nutritious, tasty and enjoyable, and look the same as the "normal" food I give his brother. I often feel guilty for creating a stressful environment related to meals and worry I have instilled a bad relationship with food in Braxton.

It's More Than Just a Diet

My husband and I have realized over the last two years that despite how well we try to manage Braxton's PKU through his diet, the disease's impact extends far beyond the kitchen table. We had to learn how to draw Braxton's blood so that we can test and monitor his Phe levels every other week. We rarely go out to restaurants anymore—it's never fun to feel the judging stares of other patrons as I weigh my son's french fries. Even going to eat at friends' houses can be challenging. Our family members and friends are amazing and sympathetic to Braxton's dietary needs but I'm still aware that it presents an inconvenience and try to be accommodating when possible.

An unexpected challenge we currently face is how to ensure that Braxton's life is not defined by PKU. When he meets new people, they often ask if he is "the one with PKU" or "the one who can't eat protein," but Braxton's condition is the least interesting thing about him. I want him to be known as the boy who has a ton of energy, who loves dinosaurs and monster trucks, who already enjoys every sport and stays amused for hours when given a baseball and bat. When people get to know him, they realize that this "rare" child is as normal as they come!

Using My Voice

With promising additional treatment options for PKU in development, my focus in the meantime is to ensure that Braxton and others like him have access to the formulas and foods they need to develop properly and thrive. Health insurance does not cover the cost of medical grade formulas and low-protein foods that patients need, in some cases. Families often find themselves struggling financially as a result.

In 2021, I began speaking out as an advocate for the Medical Nutrition Equity Act (HR 3783/S 2013), which would require health insurance companies to cover the high-cost formulas and foods that people with PKU and other allied disorders need on a daily basis. This summer, I was given the opportunity to speak with Wyoming Congresswoman Liz Cheney and Senators John Barrasso and Cynthia Lummis and ask them to become co-sponsors of the bill.  It has been an extremely rewarding experience and I have learned that while the legislative process is complicated and can be overwhelming, there are ways of advocating for people like Braxton at state and local levels. I am excited to see where my role as an advocate will lead.

Moving Forward

Perhaps the most important thing I have learned in the last two years is that a PKU diagnosis does not mean the end of the world or that your family is alone. And with potential new treatment options on the horizon, there is hope for the future. In the days and weeks following a PKU diagnosis, it is important to reach out to other affected patients and families to find a community of support and additional information whether through social media or advocacy organizations. My Instagram page (@kayla_withoutthe_y) caters to new caregivers, patients and others impacted by PKU who can ask questions, feel supported and get new ideas.

It is easy to feel isolated and overwhelmed when faced with a PKU diagnosis, whether you are a parent, caregiver or patient. This may be a rare disease, but with thousands of people in the U.S. living with PKU, there are many with similar experiences who can provide you and your family with help and support—all you need to do is ask!