Living with Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome
A rare genetic condition of the urea cycle, which clears ammonia, causing brain, liver, and feeding problems.
Understanding Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome
It can start in newborns with low energy, poor feeding, vomiting, and fast breathing. More often it appears in infancy, childhood, or adulthood with long-term thinking and learning problems, sudden brain illness (acute encephalopathy), blood clotting problems, or other chronic liver problems.
Signs & symptoms
Symptoms vary from person to person. GARD lists these among the most common:
- Low energy (lethargy)
- Poor feeding and vomiting
- Sudden brain illness (acute encephalopathy)
- Cognitive impairment
- Enlarged liver and reduced liver function
- Increased reflexes and poor coordination
Not everyone has every symptom. GARD's list comes from the Human Phenotype Ontology.
Diagnosis
- 1Talk with your doctor
Share the symptoms you've noticed, when they started and your family health history. Notes and photos can help.
- 2See a specialist
Specialists who may be involved include brain and nervous system specialists and genetic specialists.
- 3Consider genetic testing
Changes in SLC25A15 are linked to this condition. Genetic testing and counseling can help confirm a diagnosis and explain what it means for your family.
Care & treatment
- Care team
- Brain and nervous system specialists (neurologists); Genetic specialists (geneticists)
- Expert care
- Ask about multidisciplinary care centers for rare conditions
- Treatment
- GARD doesn't list specific treatments for this condition. Your care team will tailor care to your symptoms.
- Research
- Clinical trials and observational studies may be options. See the research section below.
General information, not medical advice. Your care team makes the decisions.
Everyday life
Living with a rare condition is easier with support.
- Connect with National Urea Cycle Disorders Foundation
- Keep notes on symptoms, changes and questions for appointments
- Ask about patient registries that help research
- Look into financial aid and travel resources for care visits
Quick facts
Changes in the SLC25A15 gene cause this condition. It is autosomal recessive, so a child inherits a changed copy of the gene from each parent.
Also known as: hhh - hyperornithinemia-hyperammonemia-homocitrullinuria syndrome; hhh syndrome; hhhs; hyperornithinemia-hyperammonemia-homocitrullinemia syndrome; hyperornithinemia-hyperammonemia-homocitrullinuria (hhh) syndrome; ornithine carrier deficiency
Patient organizations
- National Urea Cycle Disorders FoundationHyperornithinemia-hyperammonemia-homocitrullinuria syndrome · United States
You are more than your diagnosis
Perspectives from people navigating life with Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome.
Explore research for Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome
Explore actively recruiting Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome studies with HealthSpark.
Find actively recruiting studies for Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome with HealthSpark. Share your city to explore research near you.
- Recruiting studies from ClinicalTrials.gov
- Share your city to look for research near you
- Eligibility is confirmed by the study team
Powered by HealthSpark, our AI chat helper
I can help you find recruiting Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome studies. Enter a ZIP code, address or city below and I'll look within 50 miles.
Powered by HealthSpark, our AI chat helper · Study information from ClinicalTrials.gov · Eligibility is confirmed by the study team.
Get Signals for Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome
Stay in the loop with community stories and updates from medical researchers.
Create a living journal that talks back
HealthStory evolves private journaling with a living AI journal that talks back and asks thoughtful questions, helping you capture your Hyperornithinemia-hyperammonemia-homocitrullinuria syndrome experiences more deeply and prepare for better conversations with your doctors and care team.
Your journal is private. Sharing your story publicly is a separate choice, made with Share your story above.