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

Carnitine palmitoyltransferase 2 deficiency



Other Names:
Carnitine palmitoyltransferase deficiency type 2; CPT2; Carnitine palmitoyltransferase II (CPT II) deficiency
Categories:

Carnitine palmitoyltransferase 2 (CPT2) deficiency is a condition that prevents the body from using certain fats for energy, particularly during periods without food (fasting). There are three main types of CPT2 deficiency: a lethal neonatal form, a severe infantile hepatocardiomuscular form, and a myopathic form.[1] The neonatal and infantile forms are severe multisystemic diseases characterized by liver failure with hypoketotic hypoglycemia (extremely low levels of ketones (substances produced when fat cells break down in the blood) and low blood sugar), cardiomyopathy, seizures, and early death. The myopathic form is characterized by exercise-induced muscle pain and weakness and occasional myoglobinuria (rust-colored urine indicating breakdown of muscle tissue).[2] Mutations in the CPT2 gene cause CPT2 deficiency. It is inherited in an autosomal recessive pattern.[1] Treatment is based on avoidance of prolonged fasting and a low-fat and high-carbohydrate diet.[3]  
Last updated: 5/29/2012

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 16 |
Medical Terms Other Names
Learn More:
HPO ID
80%-99% of people have these symptoms
Abnormal circulating acetylcarnitine concentration 0012071
Abnormal circulating long-chain fatty-acid concentration 0010964
Cardiomyopathy
Disease of the heart muscle
0001638
Elevated hepatic transaminase
High liver enzymes
0002910
Hepatomegaly
Enlarged liver
0002240
Muscle weakness
Muscular weakness
0001324
Myalgia
Muscle ache
Muscle pain
[ more ]
0003326
Myopathy
Muscle tissue disease
0003198
Seizure 0001250
30%-79% of people have these symptoms
Cerebral calcification
Abnormal deposits of calcium in the brain
0002514
Multicystic kidney dysplasia 0000003
Renal insufficiency
Renal failure
Renal failure in adulthood
[ more ]
0000083
5%-29% of people have these symptoms
Coma 0001259
Encephalitis
Brain inflammation
0002383
Hypoglycemia
Low blood sugar
0001943
Sudden cardiac death
Premature sudden cardiac death
0001645
Showing of 16 |
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.

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.
  • 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.
  • The Newborn Screening Coding and Terminology Guide created by the National Library of Medicine (NLM) at the National Institutes of Health (NIH) promotes and facilitates the use of electronic health data standards in recording and transmitting newborn screening test results. The Web site includes standard codes and terminology for newborn tests and conditions for which they screen, and links to related sites. Click on the link to view details for this condition.
  • 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.
  • Simone Albers, et al.  Detection of Neonatal Carnitine Palmitoyltransferase II Deficiency by Expanded Newborn Screening With Tandem Mass SpectrometryPediatrics, Jun 2001;107:e103.

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

  • 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.  

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
The differential diagnosis for the myopathic form should include McArdle disease, Duchenne muscular dystrophy, and cytochrome c oxidase deficiency (see these terms) among others, and carnitine-acylcarnitine translocase deficiency (CACT) and very-long-chain acyl-CoA dehydrogenase deficiency (see these terms) for the infantile and neonatal forms
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

  • The U.S. National Institutes of Health, through the National Library of Medicine, developed ClinicalTrials.gov to provide patients, family members, and members of the public with current information on clinical research studies. There is a study titled Pediatric Patients With Metabolic or Other Genetic Disorders which may be of interest to you.
  • ClinicalTrials.gov lists trials that are related to Carnitine palmitoyltransferase 2 deficiency. 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.

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


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 Carnitine palmitoyltransferase 2 deficiency. This website is maintained by the National Library of Medicine.
  • 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.
  • 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 Carnitine palmitoyltransferase 2 deficiency. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.


  1. Carnitine palmitoyltransferase II deficiency. Genetics Home Reference (GHR). November 2010; http://www.ghr.nlm.nih.gov/condition/carnitine-palmitoyltransferase-ii-deficiency. Accessed 5/29/2012.
  2. Wieser T. Carnitine Palmitoyltransferase II Deficiency. GeneReviews. October 2011; http://www.ncbi.nlm.nih.gov/books/NBK1253/. Accessed 5/29/2012.
  3. Bennett M, Stanley C. Carnitine palmitoyl transferase II deficiency. Orphanet. April2010; http://www.orpha.net/consor/cgi-bin/OC_Exp.php?Lng=EN&Expert=157. Accessed 5/29/2012.