Meet the flok: Urea Cycle Disorders (UCDs)

Our “Meet the flok” series profiles the inherited conditions of protein metabolism that make up our diverse community: Classical Homocystinuria, Maple Syrup Urine Disease, Organic Acidemias, Phenylketonuria, Tyrosinemia, and Urea Cycle Disorders. Each article highlights personal stories of resilience and the efforts of advocacy leaders to support individuals facing each condition. We hope this series will educate, inspire, and unite our flok community in a shared mission to improve treatment for our rare conditions.

Alyssa and Aurelya Olson
Argininosuccinic Aciduria 

Alyssa Olson is mother to nine-year-old Aurelya, who was born with a metabolic disorder called Argininosuccinic Aciduria (ASA). She glows with pride talking about her daughter, who she describes as “a bright light with a golden heart,” and shares her family’s experience over the last several years adjusting to this rare diagnosis.  

An Unexpected Diagnosis 

Aurelya entered the world five weeks before her due date, avoiding the NICU by a narrow margin. Despite an early arrival, she was a healthy baby and discharged home a few days later with parents Alyssa and Nic Olson. Soon after, they received a vague phone call from Aurelya’s primary care clinic saying her Newborn Screening blood results were abnormal: she had elevated citrulline and an argininosuccinic level five times the normal value. Without further explanation, the clinic recommended immediate medical attention. The Olsons brought Aurelya to the hospital for more bloodwork and discovered her ammonia level was also elevated. The care team confirmed a diagnosis of a urea cycle disorder (UCD) called Argininosuccinic Aciduria (ASA) – the first case documented in the state of New Hampshire since its addition to the state’s newborn screening panel seven years earlier.   

While both Alyssa and Nick are medical professionals – an infection-prevention nurse and a pathologist, respectively – they were unfamiliar with ASA. And at the time, there was limited available research on health outcomes for babies diagnosed and treated at birth. “The literature online was very frightening,” Alyssa recalls, “and showed high mortality rates.”  

They learned the rare condition is caused by an enzyme deficiency that disrupts the urea cycle, limiting the body’s ability to break down nitrogen and produce the amino acid arginine. This results in excess nitrogen that accumulates as ammonia–with toxic effects on the brain if left untreated. For newborns, immediate intervention is needed to prevent a hyperammonemic crisis that can cause respiratory distress, seizures, and cognitive impairment.  

The Olsons spent the next several days in the hospital with their daughter while she underwent treatment for jaundice and hydration to stabilize her amino acid and ammonia levels. The genetics team then transferred Aurelya’s care to Boston Children’s Hospital, and the Olsons started her new care regimen that involves daily medications, supplements, a strict low-protein diet, and routine bloodwork.  

Uncharted Territory  

Given Aurelya’s diagnosis was the first in New Hampshire, the protocols for ASA management were not well-established, and the Olsons faced several hurdles. They traveled bi-weekly from New Hampshire to Boston to meet with her genetics team, and searched for a pharmacy that would supply her ammonia-scavenging drug and arginine supplement. Both medications were costly and hard to find. The Olsons eventually found a pharmacy that agreed to overnight-ship the medication on ice every two weeks – a process that required extensive coordination.  

The medication also made Aurelya vomit – a significant concern with ASA as ammonia levels can increase with sickness, dehydration, or periods of fasting. For the same reason, they woke Aurelya every two hours to eat to prevent catabolism, in which the body breaks down its own protein stores and causes ammonia to build up. The Olsons did this for six months before Aurelya could safely sleep for longer stretches of time.  

When Aurelya started solid foods, her protein tolerance was very low. It took time to figure out which foods she liked within her daily allowance, and to carefully measure how much protein she consumed from the amount served. The Olsons turned to Cook for Love for low-protein food ideas and the How Much Phe tool for dietary tracking – now a part of the flok app. They also found incredible community support through the associated social media forums.  Alyssa reflects, "How Much Phe has truly been a lifesaver for us – I don’t know how we would have made it without that resource.”  

As the Olsons hit a stride with dietary tracking, they also began compounding Aurelya’s arginine at home instead of relying on the pharmacy. They used a specialized scale to weigh and mix powder, water, and flavoring – a practice they’ve continued for the last nine years to minimize care coordination. Alyssa reflects, “Looking back, it was just our lifestyle. But a lot of mental energy went into all of it.”  

Aurelya has been stable for several years, with no hospitalizations since she was 18 months old – a testament to the Olson’s diligent management of their daughter's complex care plan. 

ASA Advocacy in School and Community Connection  

Like most inherited metabolic conditions, the neurocognitive effects of ASA are not well understood and vary from person to person. Aurelya started an early childhood intervention plan at 18 months of age that included occupational and speech therapy for a mild learning disability and transitioned to an individualized education program (IEP) at age three. Alyssa describes the IEP process in South Dakota, where they now live, as very challenging to navigate. ASA is not considered a qualifying condition and while Aurelya benefits from added support, she performs above the testing thresholds to meet requirements – “She’s a really smart cookie,” her mother notes.  

Alyssa continues to advocate for Aurelya, who now has a 504 for ADHD – a diagnosis determined by a neuropsychological evaluation a few years ago. Aurelya is part of a research study on ASA that requires neuropsychological testing every two years. While the research study enhances medical understanding of the rare condition for the broader metabolic community by exploring ASA’s neurocognitive impact, the testing also informs the Olsons how to best support Aurelya academically.  

Now a third grader, Aurelya is bubbly, outgoing, and flourishing in school. Her teachers describe her as a hardworking model student who is quick to help others. She also shows insight into her metabolic condition, explaining to her classmates that she counts protein in the food she eats to stay healthy. She drinks her medical formula in the morning and evening and takes her arginine supplement three times a day – once during school hours in the nurse’s office. While Aurelya’s routine may differ from that of other kids, her parents build confidence by reminding her everyone has unique health needs. Alyssa says, “We focus on safety, eating what makes her feel good, and paying attention to her body.” 

Outside of school, Aurelya loves Girl Scouts, soccer, riding horses, swimming, softball, and making arts and crafts. She also enjoys spending time with her younger brother Ripley, who Alyssa describes as “her protector.” Their family recently attended the National Urea Cycle Disorders Foundation Family Conference in Texas where Aurelya spent time with a friend close in age who also has ASA. Alyssa finds value in talking with the broader UCD community, normalizing Aurelya’s experience through peer connection, and learning from families whose children are older in age. She says, “We’ve seen that things can get out of whack during puberty, and it weighs on us – what could happen? But all we can do is what we’ve been doing and stay diligent.”  

While Alyssa acknowledges their journey has been difficult at times, she remains optimistic for Aurelya’s future and provides encouragement to other families who receive a diagnosis of ASA – “Life may feel like it crashed into a brick wall, but through guidance from medical specialists, support groups, technology, and resources, you'll find yourself surrounded by a community that welcomes you and is there when you need them. And you’ll realize you’re doing it!” 

Amy Englert  
Ornithine Transcarbamylase Deficiency  

Amy Englert lives with her husband and Jack Russell terriers in Rochester, New York where she works full-time in the engineering department of their town. She’s an avid traveler and yogi who leads a full life amid the daily challenges of her condition, Ornithine Transcarbamylase Deficiency (OTC), a type of Urea Cycle Disorder (UCD). While many UCDs are detected by Newborn Screening or a hyperammonemic crisis within the first few days of life, Amy’s symptoms didn’t emerge until she was 12. She reflects on the emergency hospitalization that led to her diagnosis, and how the condition has shaped her lifestyle over the last few decades.  

Right Place, Right Time 

Amy traveled to her extended family’s cottage in Chincoteague Island, Virginia in the spring of 1985. She felt sick and took a break from swimming to eat lunch: a roast beef sandwich and turkey noodle soup. When her family returned to the cottage shortly after, they found Amy unresponsive. A helicopter airlifted her to Johns Hopkins Hospital where she was admitted to the pediatric intensive care unit. A physician named Dr. Saul Brusilow took over Amy’s case and determined she was in a hyperammonemic crisis due to toxic elevations of ammonia in her blood. After further testing he confirmed a diagnosis of OTC, a rare metabolic condition in which an enzyme deficiency disrupts the body’s natural urea cycle to metabolize and dispose of nitrogen, causing ammonia buildup. Amy has a late-onset variant of OTC, and the combination of dehydration, physical activity, and high protein foods on her beach trip sparked the metabolic crisis. 

Once she emerged from the coma 24 hours later, Amy and her family learned Dr. Brusilow was the leading researcher and expert on UCDs, which explained his swift detection of her rare condition. At that time, there were no FDA-approved treatments for its management, and he had developed an experimental drug therapy to trial on Amy. Reflecting on her hospitalization under Dr. Brusilow’s care, she believes “fate played a hand.” 

Amy spent the next three weeks inpatient at the hospital and began a grueling treatment regimen: 34 pills a day, a low-protein diet, and frequent blood work to monitor her ammonia levels. 17 of the pills prevented ammonia elevation, and the other 17 were a substitute for drinking medical formula to ensure her body received adequate protein for growth and development. The experimental treatment seemed to be working and Amy returned home. Unfortunately, the medications had many side effects she had to cope with in the following months. Unfortunately, the medications had many side effects. She took a drug that caused uncontrollable body odor, noting, “Middle school was hard.”  

In addition to the medication burden, there were limited low-protein foods on the market and no internet or tools to support protein tracking in the mid-eighties. Amy recalls this challenging period, and the incredible support provided by her parents. Her mother said, “Everyone has something they are dealing with,”– words that anchored her as a teen and in the ensuing years as she adjusted to her new lifestyle.  

Navigating Daily Life with OTC  

Treatment of urea cycle disorders varies from person to person depending on the type and severity, and there is no one-size-fits-all approach. Amy’s care team experimented with several drugs to control her ammonia levels, and she was hospitalized at least annually during an acute sickness. She eventually was prescribed an ammonia-scavenger drug called Ravicti; paired with a low-protein diet, the medication has helped her avoid hospitalization for the last eight years.  [ed. Ravicti is manufactured by Amgen, a capacity-building sponsor of flok].

Even with effective medication and dietary management, many other factors can trigger a hyperammonemic crisis: exercise, stress, illness, heat, and dehydration. Amy eats more protein when she works out, uses cooling packs, and drinks plenty of water on hot days. With time and experience, Amy has learned how her body reacts to adverse conditions and what specific actions to take. “Sometimes I feel like I’m walking a tightrope because there are so many things in my daily life I have to consider.”  

Amy carries an emergency preparedness plan with her everywhere; it outlines her condition and treatment needs in the event she can’t speak for herself. The plan includes her three-times-daily ammonia-scavenger medication, which requires refrigeration. While she has a routine for managing the medication at work and home, travel requires extra preparation. Amy reflects on a recent camping trip to Mount Zion National Park, in which she packed a mini fridge for medication storage – “You can do anything you want – with a lot of careful planning!” 

A Voice for the Community  

Amy’s experience with OTC compels her to educate and support others within the UCD community. She speaks annually at her geneticist’s class through Rochester Strong Hospital and has written articles for Connecting Families UCD Foundation. She tackles important topics like whether to share a diagnosis with an employer. Amy says she “learned the hard way” after experiencing a hyperammonemic episode at work, in which she became disoriented and slurred her words – symptoms often mistaken for inebriation. Amy endorses transparency both for her own safety, and for de-stigmatizing life with a metabolic condition.  

Amy also shed light on the topic of family planning, and whether to tell a partner about being a carrier for a genetic condition. She led a webinar for Remember the Girls – an organization that supports female carriers of X-linked conditions – to share her wisdom. While all other UCDs are autosomal recessive and require a genetic pairing from both parents, OTC is X-linked and passed from mother to child. Interestingly, Amy discovered that her diagnosis was caused by de novo mutation* and that her mother is not a carrier. 

Her admirable zeal for discussing these difficult topics stems from her own positive experience with peer support from her UCD community. Amy shares, “No one understands you like another person with your condition.”  

While Amy is thriving despite the challenges of OTC, like many of her peers, she wonders what tomorrow holds: “At 51, I’m one of the oldest people with this condition. There aren’t many people that received good treatment ahead of me to know what my future will look like.”  Amy stresses the need for longitudinal studies to better understand OTC’s trajectory over time, and to inform how condition management might change with age. Until then, Amy illuminates the path forward for individuals navigating a UCD, empowering others with honest discussion. 

*A “de novo mutation” is a spontaneous alteration in a gene sequence that is not inherited from an individual’s parents. In OTC, some individuals develop the condition from this mutation, rather than inherit the gene variant from their mother on the X chromosome.