National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Argininosuccinic aciduria


Other Names:
Arginino succinase deficiency; Inborn error of urea synthesis, arginino succinic type; Urea cycle disorder, arginino succinase type; Arginino succinase deficiency; Inborn error of urea synthesis, arginino succinic type; Urea cycle disorder, arginino succinase type; Argininosuccinate lyase deficiency; ASL deficiency; ASA deficiency; Argininosuccinicaciduria; Argininosuccinate acidemia; Argininosuccinic acid lyase deficiency See More
Categories:
This disease is grouped under:
Argininosuccinic aciduria is an inherited disorder that causes ammonia to accumulate in the blood. Ammonia, which is formed when proteins are broken down in the body, is toxic if the levels become too high. The nervous system is especially sensitive to the effects of excess ammonia. Argininosuccinic aciduria usually becomes evident in the first few days of life. An infant with argininosuccinic aciduria may be lacking in energy (lethargic) or unwilling to eat, and have poorly controlled breathing rate or body temperature. Some babies with this disorder experience seizures or unusual body movements, or go into a coma. Complications from argininosuccinic aciduria may include developmental delay, intellectual disability, progressive liver damage, skin lesions, and brittle hair. The condition is caused by mutations in the ASL gene and is inherited in an autosomal recessive pattern.[1] Long-term management includes dietary restriction of protein and supplementation with arginine. Acute crises may be treated by discontinuing oral protein intake, supplementing oral intake with intravenous lipids and/or glucose, and use of intravenous arginine and nitrogen scavenging therapy. If ammonia levels do not normalize, hemodialysis may be necessary.[2]
Last updated: 4/29/2011

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

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Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Aminoaciduria
High urine amino acid levels
Increased levels of animo acids in urine
[ more ] 		0003355
Hyperglutaminemia
High plasma glutamine
0003217
Hypoargininemia
Low blood arginine levels
0005961
Oroticaciduria
High urine orotic acid levels
0003218
30%-79% of people have these symptoms
Ataxia 0001251
EEG abnormality 0002353
Hyperammonemia
High blood ammonia levels
0001987
Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific
Mental-retardation
[ more ] 		0001249
Short stature
Decreased body height
Small stature
[ more ] 		0004322
5%-29% of people have these symptoms
Abnormal hair quantity 0011362
Trichorrhexis nodosa 0009886
Percent of people who have these symptoms is not available through HPO
Autosomal recessive inheritance 0000007
Brittle hair 0002299
Cerebral edema
Swelling of brain
0002181
Coma 0001259
Dry hair 0011359
Elevated serum aspartate aminotransferase 0031956
Episodic ammonia intoxication 0001951
Failure to thrive
Faltering weight
Weight faltering
[ more ] 		0001508
Feeding difficulties in infancy 0008872
Global developmental delay 0001263
Hepatic fibrosis 0001395
Hepatomegaly
Enlarged liver
0002240
Irritability
Irritable
0000737
Lethargy 0001254
Neonatal onset 0003623
Protein avoidance 0002038
Respiratory alkalosis 0001950
Seizure 0001250
Vomiting
Throwing up
0002013
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Last updated: 7/1/2020

Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.

Newborn Screening

  • An ACTion (ACT) sheet is available for this condition that describes the short-term actions a health professional should follow when an infant has a positive newborn screening result. ACT sheets were developed by experts in collaboration with the American College of Medical Genetics.
  • An Algorithm flowchart is available for this condition for determining the final diagnosis in an infant with a positive newborn screening result. Algorithms are developed by experts in collaboration with the American College of Medical Genetics.
  • The Newborn Screening Coding and Terminology Guide has information on the standard codes used for newborn screening tests. Using these standards helps compare data across different laboratories. This resource was created by the National Library of Medicine.
  • Baby's First Test is the nation's newborn screening education center for families and providers. This site provides information and resources about screening at the local, state, and national levels and serves as the Clearinghouse for newborn screening information.
  • National Newborn Screening and Global Resource Center (NNSGRC) provides information and resources in the area of newborn screening and genetics to benefit health professionals, the public health community, consumers and government officials.

The resources below provide information about treatment options for this condition. If you have questions about which treatment is right for you, talk to your healthcare professional.

Management Guidelines

  • The NORD Physician Guide for Argininosuccinic aciduria was developed as a free service of the National Organization for Rare Disorders (NORD) and it's medical advisors.  The guides provide a resource for clinicians about specific rare disorders to facilitate diagnosis and treatment of their patients with this condition. 
  • Orphanet Emergency Guidelines is an article which is expert-authored and peer-reviewed that is intended to guide health care professionals in emergency situations involving this condition.  

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

  • Glycerol phenylbutyrate (Brand name: Ravicti) - Manufactured by Horizon Pharma, Inc.
    FDA-approved indication: Use as a nitrogen-binding adjunctive therapy for chronic management of adult and pediatric patients at least 2 months of age with urea cycle disorders (UCDs) that cannot be managed by dietary protein restriction and/or amino acid supplementation alone. RAVICTI must be used with dietary protein restriction and, in some cases, dietary supplements (eg, essential amino acids, arginine, citrulline, protein-free calorie supplements).
    National Library of Medicine Drug Information Portal

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses include other urea cycle disorders such as carbamoyl-phosphate synthetase 1 deficiency, ornithine transcarbamylase deficiency, citrullinemia type I and arginase deficiency, although neither of these exhibits the classical marker argininosuccinic acid.
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Argininosuccinic aciduria. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Patient Registry

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

  • Good Days provides help to patients with life-altering conditions. Assistance includes help with the cost of medications and travel.
  • The HealthWell Foundation provides financial assistance for underinsured patients living with chronic and life-altering conditions. They offer help with drug copayments, deductibles, and health insurance premiums for patients with specific diseases. The disease fund status can change over time, so you may need to check back if funds are not currently available.

Education Resources

  • The Genetics Education Materials for School Success (GEMSS) aims to assure that all children with genetic health conditions succeed in school-life. Their Web site offers general and condition-specific education resources to help teachers and parents better understand the needs of students who have genetic conditions.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • Genetics Home Reference (GHR) contains information on Argininosuccinic aciduria. This website is maintained by the National Library of Medicine.
  • MedlinePlus.gov provides more information on urea cycle disorders in general. MedlinePlus is a Web site designed by the National Library of Medicine to help you research your health questions.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
  • The Screening, Technology And Research in Genetics (STAR-G) Project has a fact sheet on this condition, which was written specifically for families that have received a diagnosis as a result of newborn screening. This fact sheet provides general information about the condition and answers questions that are of particular concern to parents.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Argininosuccinic aciduria. Click on the link to view a sample search on this topic.

News

Other Conferences

  • Reaching for a Cure: 2011 NUCDF Annual Conference, July 8 2011 - July 10, 2011 
    Location: Sheraton Denver Downtown, Denver, Colorado
    Description: This conference offers the unique opportunity to meet other UCD families, stay informed, and learn about new advances in research, treatment and management to improve the lives of children and adults with UCD. Working together, our NUCDF families and community of committed researchers and medical professionals are making a major impact with advances in the understanding of UCDs, accelerating research, and improved outcomes in children and adults with UCD. In the past four years, research for UCDs has increased by 400%! Let's continue the momentum and end the devastating effects of UCD.

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  1. Argininosuccinic aciduria. Genetics Home Reference (GHR). 2007; http://www.ghr.nlm.nih.gov/condition/argininosuccinic-aciduria. Accessed 4/29/2011.
  2. Nagamani SCS, Erez A, Lee B. Argininosuccinate Lyase Deficiency. GeneReviews. 2011; http://www.ncbi.nlm.nih.gov/books/NBK51784/. Accessed 4/29/2011.