HIBCH deficiency

Title

Other Names:

Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency; 3-Hydroxyisobutyryl-CoA hydrolase deficiency; Beta-hydroxyisobutyryl-CoA deacylase deficiency; Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency; 3-Hydroxyisobutyryl-CoA hydrolase deficiency; Beta-hydroxyisobutyryl-CoA deacylase deficiency; Methacrylic aciduria; Methacrylic acid toxicity; Valine metabolic defect See More

Categories:

Congenital and Genetic Diseases; Nervous System Diseases

Summary Summary

HIBCH deficiency is a rare metabolic disease. Early symptoms include poor muscle tone, poor feeding, seizures, and a gradual loss of skills. HIBCH deficiency can cause signs and symptoms similar to another disease, called Leigh syndrome.^[1] Diagnosis is aided by blood tests which show high levels of lactic acid, and imaging studies which show changes in the "globi pallidi" structure of the brain.^[2]^[1]

HIBCH deficiency occurs when a person inherits a mutation in both copies of their HIBCH gene. This pattern of inheritance is called "autosomal recessive."^[2] The HIBCH gene tells the body how to make an enzyme called 3-hyroxyisobutyryl-CoA hydrolase. When the body does not have enough working enzyme, it can not break down the amino acid valine. As a result, toxic valine metabolites build up in the body. More specifically, these toxic metabolites build up within the mitochondria of the body's cells.^[3]

Currently, there is not a cure for HIBCH deficiency. Children with HIBCH deficiency require a multidisciplinary team of doctors who can assess how the deficiency is affecting each body system and recommend appropriate treatments.

Last updated: 2/17/2017

Symptoms Symptoms

Signs and symptoms of HIBCH deficiency are very similar to Leigh syndrome, and may include:^[2]^[1]^[4]

Developmental delay (delayed motor and language skills, low muscle tone, poor feeding in infancy)
Deterioration of neurological functions during the first stages of life
Vision problems
Vomiting
Seizures
A blood test showing an increased lactic acid level
Brain lesions in the basal ganglia
Accumulation of several valine metabolites in the blood and urine, especially of “3-hydroxy-isobutyryl carnitine”, which is detected as “hydroxy-C4-carnitine” by tandem mass spectrometry (a screening technique that identify carnitine in blood and urine of children with a suspicion of having an inborn metabolic disease).

There are very few cases of HIBCH deficiency described until now. The long term outcome is not well defined yet, but the disease is known to progress (worsen) with time. Severity of HIBCH deficiency does vary. People with the deficiency may have some working enzyme. People with more functioning enzyme tend to have less severe symptoms, than those with little to no enzyme function.^[5] Physical stress, infectious illness (such as viral infections), and fasting can trigger a sudden worsening of symptoms in all people with HIBCH deficiency.^[5]

Last updated: 2/17/2017

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.

Showing of 20 |

Medical Terms	Other Names	Learn More: HPO ID
80%-99% of people have these symptoms
Muscular hypotonia	Low or weak muscle tone	0001252
Percent of people who have these symptoms is not available through HPO
Abnormal facial shape	Unusual facial appearance	0001999
Abnormal vertebral morphology		0003468
Abnormality of the vertebral column	Abnormal spine Abnormal vertebral column Abnormality of the spine [ more ]	0000925
Agenesis of corpus callosum		0001274
Aminoaciduria	High urine amino acid levels Increased levels of animo acids in urine [ more ]	0003355
Autosomal recessive inheritance		0000007
Developmental regression	Loss of developmental milestones Mental deterioration in childhood [ more ]	0002376
Dysmetria	Lack of coordination of movement	0001310
Dystonia		0001332
Epicanthus	Eye folds Prominent eye folds [ more ]	0000286
Feeding difficulties	Feeding problems Poor feeding [ more ]	0011968
Generalized hypotonia	Decreased muscle tone Low muscle tone [ more ]	0001290
Global developmental delay		0001263
Infantile onset	Onset in first year of life Onset in infancy [ more ]	0003593
Myoclonus		0001336
Nystagmus	Involuntary, rapid, rhythmic eye movements	0000639
Seizures	Seizure	0001250
Strabismus	Cross-eyed Squint Squint eyes [ more ]	0000486
Tetralogy of Fallot		0001636

Showing of 20 |

Do you have more information about symptoms of this disease? We want to hear from you.

Last updated: 11/1/2018

Do you have updated information on this disease? We want to hear from you.

Cause Cause

HIBCH deficiency is caused by mutations in the HIBCH gene. The deficiency results in a block of the breakdown (catabolism) of valine. This leads to a build up of toxic valine metabolites within the mitochondria in the body's cells.[2] Valine is an essential amino acid, which means that it cannot be made by the body, but instead must be obtained from diet.[3]

Valine catabolism involves several steps with different enzymes acting in each step. The 3-hydroxy-isobutyryl-CoA hydrolase (HIBCH) is a mitochondrial enzyme that acts in the 5^th step, therefore all the substances that are produced before this step build-up. One of the metabolites, known as methacrylyl-CoA, can react with other mitochondrial enzymes and disrupt their activities. As a result, patients with HIBCH deficiency have features similar to Leigh disease and other mitochondrial disorders.^[2]^[1]^[6]

HIBCH deficiency is considered an organic acidemia. Organic acidemias are so named because they disrupt amino acid metabolism. This causes an increase in organic acid levels. In HIBCH deficiency we see an increase in lactic acid.

HIBCH deficiency can also be considered a mitochondrial disease, because it disrupts mitochondrial enzymes.

The involvement of the globi pallidi in HIBCH deficiency is one of the main features of the disease. The globi pallidi is part of the basal ganglia in the brain. The reason that the globi pallidi is affected may be due to a failure in providing energy to the brain which results in the early death of brain cells. This finding is also a feature of other mitochondrial diseases (including Leigh syndrome) and of other organic acidemias.^[1]

HIBCH is also involved in a second metabolic pathway. This pathway is related to propionate metabolism. Propionate is a substance produced by the break down of some aminoacids. However, the HIBCH gene mutations do not appear to result in adverse symptoms related to this pathway.^[2]

Last updated: 2/17/2017

Treatment Treatment

Treatment of HIBCH deficiency involves frequent carbohydrate-rich meals, along with coenzyme Q10, vitamin C, and vitamin E supplementation.^[5]

People with HIBCH deficiency may also benefit from a low-valine diet with carnitine and N-acetyl-cysteine supplementation.^[5]

Prompt, supportive, treatment during periods of physical stress and viral illness is vital. This may involve frequent infusions of bicarbonate, plus additional supports as required.^[5]

We strongly recommend that these and other treatment options be carefully reviewed with a healthcare provider.

Last updated: 2/22/2017

Find a Specialist Find a Specialist

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

To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. Online directories are provided by the American College of Medical Genetics and the National Society of Genetic Counselors. If you need additional help, contact a GARD Information Specialist. You can also learn more about genetic consultations from Genetics Home Reference.

Organizations Organizations

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

Metabolic Support UK
5 Hilliards Court
Sandpiper Way
Chester Business Park
Chester, CH4 9QP United Kingdom
Toll-free: 0800 652 3181
Telephone: 0845 241 2173
E-mail: https://www.metabolicsupportuk.org/contact-us
Website: https://www.metabolicsupportuk.org
MitoAction
PO Box 51474
Boston, MA 02205
Toll-free: 888-648-6228
Telephone: 1-888-MITO-411 (648-6411) for support line
E-mail: info@mitoaction.org
Website: http://www.mitoaction.org
Organic Acidemia Association
9040 Duluth Street
Golden Valley, MN 55427
Telephone: 763-559-1797
Fax: 866-539-4060
E-mail: mkstagni@gmail.com
Website: http://www.oaanews.org/
Pediatric Brain Foundation
2144 E. Republic Rd.
Building B, Suite 202
Springfield, MO 65804
Telephone: 417-887-4242
E-mail: info@pediatricbrainfoundation.org
Website: http://www.pediatricbrainfoundation.org/
The Mitochondria Research and Medicine Society
PO Box 55322
BLSC Building, Room # 3-316
Elm and Carlton Streets
Birmingham, AL
Telephone: 716-907-4349
Fax: 716-845-1047
E-mail: contact@mitoresearch.org
Website: http://www.mitoresearch.org
United Mitochondrial Disease Foundation
8085 Saltsburg Road, Suite 201
Pittsburgh, PA 15239
Toll-free: 888-317-8633
Telephone: 412-793-8077
Fax: 412-793-6477
E-mail: info@umdf.org
Website: http://www.umdf.org

Do you know of an organization? We want to hear from you.

Learn More Learn More

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.

In-Depth Information

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.

News & Events News & Events

News

The NIH Undiagnosed Diseases Network Expands
September 26, 2018

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References References

Reuter MS & cols. HIBCH deficiency in a patient with phenotypic characteristics of mitochondrial disorders. Am J Med Genet A. 2014; 164A(12):3162-9. http://www.medscape.com/medline/abstract/25251209.
Petersc H & Ferdinanddussed S, Ruiterd JP & Wandersd RJA. Metabolite studies in HIBCH and ECHS1 defects: Implications for screening. Molecular Genetics and Metabolism. August, 2015; 115 (4):168–173. http://www.sciencedirect.com/science/article/pii/S1096719215300275.
Jorde LB. Aminoacid Metabolism. In: Kaplan Medical, Inc. Biochemistrhy. USMLE step 1. 2016; 252-253.
3-hydroxyisobutryl-CoA hydrolase deficiency. OMIM. 2015; https://www.omim.org/entry/250620.
Yamada K, Naiki M, Hoshino S et al.,. Clinical and biochemical characterization of 3-hydroxyisobutyryl-CoA hydrolase (HIBCH) deficiency that causes Leigh-like disease and ketoacidosis. Mol Genet Metab Rep. 2014; 1:455–460. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5121361/. Accessed 2/22/2017.
Brown G K & cols. Beta-hydroxyisobutyryl coenzyme A deacylase deficiency: a defect in valine metabolism associated with physical malformations. Pediatrics. 1982; 70:532-538. https://www.ncbi.nlm.nih.gov/pubmed/7122152.
What is Mitochondrial Disease?. United Mitochondrial Disease Foundation. http://www.umdf.org/what-is-mitochondrial-disease/. Accessed 2/21/2017.
Ravenscroft G & cols. Recurrent de novo BICD2 mutation associated with arthrogryposis multiplex congenita and bilateral perisylvian polymicrogyria. Neuromuscul Disord. November, 2016; 26(11):744-748. https://www.ncbi.nlm.nih.gov/pubmed/27751653.