Home > Newborn Disorders > CPT1 deficiency
CPT1 deficiency
Screening
Tested By
tandem mass spectrometry (MS/MS); sensitivity=100%; specificity=N/A% [Schulze: 2003]Names
CPT1 deficiency
Carnitine palmitoyl transferase deficiency, type 1A (CPT 1)
Carnitine palmitoyl transferase 1 deficiency
CPT1A
CPT 1 liver
Overview
Carnitine palmitoyl transferase 1A (CPT1) is a mitochondrial enzyme involved in the conjugation of fatty acids to carnitine for subsequent trantransfer inside mitochondria through the action of a translocase. Deficiency of CPT1 results in impaired energy production, usually manifest during periods of prolonged fasting and/or increased energy demands (fever, stress), resulting in rapid onset of hypoglycemic crises. CPT1A is predominantly expressed in the liver and the muscle and the heart are not primarily affected in this condition.Prevalence
CPT 1 is rare [Schulze: 2003], with fewer than 40 known cases. [CPT1 deficiency (GeneReviews)]Clinical Characteristics
With treatment, episodes of hypoglycemia, and consequent neurologic injury, may be avoided. Without treatment, injury from hypoglycemic episodes may lead to developmental delay, seizures, coma, and death. Acute fatty liver of pregnancy may occur in a heterozygous mother of a homozygous fetus.Initial signs/symptoms typically begin suddenly in association with an illness between eight and eighteen months of life and may be life-threatening. They usually include:
- poor appetite,
- vomiting,
- lethargy,
- lab findings:
- hyperammonemia,
- elevated transaminases,
- metabolic acidosis, and
- hypoglycemia.
Follow-up on positive screening test
Quantitative plasma acylcarnitine profile, CPT1 enzyme analysis, CPT1A gene sequencing. The increased C0/(C16+C18) ratio is better detected on blood spotted on filter paper than in plasma. In plasma, C0 can be only mildly increased with low levels of C16 and C18.Primary care management
Upon notification of the + screen
- Contact the family and evaluate the infant for lethargy, poor feeding, or hepatomegaly;
- Provide emergency treatment/referral for symptoms of hypoglycemia, lethargy, or seizures;
- To confirm the diagnosis, work with the following service(s): Utah Newborn Screening Program, (801-584-8256); See also Services below;
- For evaluation and ongoing collaborative management, consult the following service(s): Medical Genetics, (801-231-3599); See also Services below;
If the diagnosis is confirmed
- Educate the family regarding signs, symptoms, and the need to avoid fasting and to seek urgent care when the infant becomes ill (see CPT1 deficiency info for parents (STAR-G) for additional information);
- Provide a letter and, when old enough, a MedicAlert bracelet indicating the risk for hypoglycemia and need for urgent treatment with IV glucose when illness or stress lead to symptoms;
- Frequent, low fat, and high carbohydrate meals and snacks and, for infants, cornstarch feedings at night as a slow-release carbohydrate source;
- Medium Chain Triglyceride (MCT) oil supplements may be indicated for some children;
- For those identified after irreversible consequences, assist in management, particularly with developmental and educational interventions.
Specialty Care Collaboration
Initial consultation and ongoing collaboration if the child is affected. A dietician may work with the family to devise an optimal approach to dietary management.Resources
Information & Support
For Professionals
CPT1 deficiency info for professionals (STAR-G)
From the Screening, Technology and Research in Genetics (STAR-G) program, one of a series of Disorder Fact Sheets for Professionals;
structured list of information about the condition, with links to more information.
ACT Sheet for CPT1 deficiency (ACMG)
(
344 KB)
Developed by the American College of Medical Genetics (ACMG), includes recommended responses to positive newborn screening
test results, diagnostic evaluation, clinical expectations, and sources of additional information. See the ACMG ACT Sheets
and Confirmatory Algorithms (link elsewhere on this page) for more info and sheets on other conditions.
ACT Sheets and Confirmatory Algorithms (ACMG)
The American College of Medical Genetics (ACMG) has developed ACTion (ACT) Sheets and algorithms for responding to positive
newborn screening test results. This page contains a table with links to all of the ACT Sheets and related algorithms.
CPT1 deficiency (GeneReviews)
Excellent review by Michael J Bennett, PhD, FRCPath, DABCC and Srinivas B Narayan, PhD, including clinical description, differential,
management, genetic counseling, molecular genetics, and a bibliography.
Resources for CPT1 deficiency (NLM)
Comprehensive compilation of links to information, articles, research, case studies, genetics, and more; from the National
Library of Medicine and the Genetic Alliance.
For Parents and Patients
CPT1 deficiency info for parents (STAR-G)
From the Screening, Technology and Research in Genetics (STAR-G) program, providing information for parents about CPT1 deficiency
and links to other sites including parent support groups.
CPT1 deficiency (Genetics Home Reference)
Excellent, detailed review aimed at patients and families from the National Library of Medicine's Genetics Home Reference
site.
United Mitochondrial Disease Foundation
The United Mitochondrial Disease Foundation site provides parents and providers with information over 40 mitochondrial diseases;
definitions of medical terms; professional articles; chapter links; newsletters; event information; and links to other sites.
Fatty Oxidation Disorders (FOD) Family Support Group
The FODsupport.org site offers a variety of information for families about fatty acid oxidation disorders, support groups,
coping, finances, and links to other sites.
National Newborn Screening & Genetics Resource Center
Provides information for families and professionals about genetic screening; links to support and advocacy groups; links to
state genetic contacts; newsletters; fact sheets; data reports; publications; and more.
Services
Newborn Screening Programs
Utah Newborn Screening Program,
more info...
44 Mario Capecchi Drive
Salt Lake City, UT 84114
Phone: 801-584-8256
Fax: 801-536-0966
http://health.utah.gov/newbornscreening
Pediatric Medical Genetics
See all Pediatric Medical Genetics services providers (3) in our database.
For other services related to this condition, browse our Services categories or search our database.
Helpful Articles
PubMed search for articles on CPT1 deficiency in the last 5 years.
Longo N, Amat di San Filippo C, Pasquali M.
Disorders of carnitine transport and the carnitine cycle.
Am J Med Genet C Semin Med Genet.
2006;142C(2):77-85.
PubMed abstract / Full Text
Authors
| Reviewing Author: | Nicola Longo MD, PhD, 3/2007 |
| Compiled and edited by: | Alfred Romeo RN, PhD, 3/2007 |
| Content Last Updated: | 9/2010 |
Page Bibliography
Schulze A, Lindner M, Kohlmuller D, Olgemoller K, Mayatepek E, Hoffmann GF.
Expanded newborn screening for inborn errors of metabolism by electrospray ionization-tandem mass spectrometry: results, outcome,
and implications.
Pediatrics.
2003;111(6 Pt 1):1399-406.
PubMed abstract