Living with Histidinemia
An inherited condition with high histidine levels in the body that usually causes no health problems.
Understanding Histidinemia
Histidine is a building block for many proteins. In most cases, histidinemia does not cause health problems, and most people don't know they have it. Rarely, people have intellectual or learning disabilities or behavior problems. A medical complication during or soon after birth might raise the chance of developmental problems.
Signs & symptoms
Most people have no symptoms. GARD lists these as less common:
- Learning disability
- Delayed development
- Behavior differences
- Being more active than typical
- Differences in speech
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 genetic specialists.
- 3Consider genetic testing
Changes in HAL 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
- 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 rare disease patient organizations for support
- 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 HAL gene cause this condition. It is autosomal recessive, so a child inherits a changed copy of the gene from each parent.
Also known as: deficiency of histidase; deficiency of histidinase; deficiency of histidine a-deaminase; deficiency of histidine ammonia-lyase; hal deficiency; high blood histidine level
Patient organizations
Rare-disease groups that can help
- Global GenesRare Diseases · United States
- National Organization for Rare DisordersRare Diseases · United States
- Genetic AllianceRare Diseases · United States
- RARE FoundationRare Diseases · United States
You are more than your diagnosis
Perspectives from people navigating life with Histidinemia.
Explore research for Histidinemia
Explore actively recruiting Histidinemia studies with HealthSpark.
Find actively recruiting studies for Histidinemia 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
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Powered by HealthSpark, our AI chat helper · Study information from ClinicalTrials.gov · Eligibility is confirmed by the study team.
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