Other Names

Very long chain acyl-CoA dehydrogenase deficiency

ACADVL deficiency

Diagnosis Coding

E71.310, long chain/very long chain acyl CoA dehydrogenase deficiency

Disorder Category

A fatty acid oxidation disorder



Elevated C14:1 +/- (acylcarnitine)

Tested By

Tandem mass spectrometry (MS/MS); sensitivity and specificity unknown [Ficicioglu: 2010]


During periods of prolonged fasting or increased energy demands (e.g., fever, stress, or lack of sleep), energy production increasingly relies on fat metabolism. Deficiency of very long-chain acyl-CoA dehydrogenase (VLCAD) impairs energy production from fats and causes metabolic crisis, cardiomyopathy, muscle pain, or myoglobinuria. Phenotypes of VLCAD deficiency include "early," "childhood," and "adult." Sudden infant deaths may occur as a result of cardiac dysfunction or arrhythmia.


In the U.S., the incidence is about 1:63,000. [Therrell: 2014]


Autosomal recessive

Maternal & Family History

There may be a family history of sudden infant death syndrome (SIDS).

Prenatal Testing

DNA testing by amniocentesis or CVS if the familial mutation is known.

Clinical Characteristics

With treatment, risk of sudden death appears to be reduced. Without treatment, sudden cardiac death is common in the early childhood form. Symptoms of VLCADD with early-onset may begin between birth and 4 months of age. Childhood onset may begin in later infancy or early childhood especially after fasting or illness. Adult onset may begin in adolescence or adulthood and may be triggered by prolonged exercise. Symptoms may be mild or severe.

Initial signs/symptoms in the early and childhood types may include:
  • Poor feeding
  • Vomiting
  • Diarrhea
  • Irritability
  • Behavior changes
  • Extreme sleepiness
  • Muscle weakness
  • Lethargy
  • Lab findings:
    • Metabolic acidosis
    • Hypoglycemia
If not treated promptly, patients may experience:
  • Hepatomegaly
  • Difficulty breathing
  • Muscle weakness with exertion
  • Arrhythmia
  • Cardiomyopathy
  • Seizures
  • Brain damage
  • Death
Adult type symptoms may include:
  • Muscle breakdown with exercise or prolonged fasting
  • Muscle aches
  • Weakness
  • Cramps
  • Reddish-brown urine
  • Kidney failure

Follow-up Testing after Positive Screen

Quantitative plasma acylcarnitine profile, urine organic acids, mutation analysis of the VLCAD gene, enzyme assay in fibroblasts, and additional biochemical genetic tests

Primary Care Management

Upon Notification of the + Screen

  • Contact the family and evaluate the infant for poor feeding, lethargy, hypotonia, hepatomegaly, or cardiac problems.
  • Recommend frequent feeding (every 3 to 4 hours in infants), including at night.
  • Provide emergency treatment and referral for symptoms of hypoglycemia, arrhythmia, or cardiac decompensation.
  • Confirm the diagnosis, work with the following service(s): Newborn Screening Services (see NW providers [1]).
  • Evaluate and continue ongoing collaborative management, consult the following service(s): Pediatric Genetics (see NW providers [1]).

If the Diagnosis is Confirmed

  • Educate the family about signs, symptoms, and the need for urgent care if the infant becomes ill (see VLCADD - Information for Parents (STAR-G) for additional information).
  • Assist with implementation of a low-fat diet supplemented with medium chain triglycerides if necessary.
  • Consider oral L-carnitine and medium chain triglyceride (MCT) oil supplements.
  • Assist in management of irreversible consequences as necessary, particularly with developmental and educational interventions.
  • See the Portal’s diagnosis and management module for VLCADD.

Specialty Care Collaboration

A dietician may work with the family to devise an optimal approach to dietary management.


Information & Support

For Professionals

VLCADD (GeneReviews)
Detailed information addressing clinical characteristics, diagnosis/testing, management, genetic counseling, and molecular pathogenesis; from the University of Washington and the National Library of Medicine.

Information about clinical features, diagnosis, management, and molecular and population genetics; Online Mendelian Inheritance in Man, authored and edited at the McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine

For Parents and Patients


Fatty Oxidation Disorders (FOD) Family Support Group
Information for families about fatty acid oxidation disorders, support groups, coping, finances, and links to other sites.


VLCADD - Information for Parents (STAR-G)
A fact sheet, written by a genetic counselor and reviewed by metabolic and genetic specialists, for families who have received an initial diagnosis of a newborn disorder; Screening, Technology and Research in Genetics.

Very long-chain acyl-CoA dehydrogenase deficiency (MedlinePlus)
Information for families that includes description, frequency, causes, inheritance, other names, and additional resources; from the National Library of Medicine.

Resources for VLCAD Deficiency (Disease InfoSearch)
Compilation of information, articles, research, case studies, and genetics links; from Genetic Alliance.


ACT Sheet for VLCADD (ACMG) (PDF Document 347 KB)
Contains short-term recommendations for clinical follow-up of the newborn who has screened positive; American College of Medical Genetics.

Confirmatory Algorithm for VLCADD (ACMG) (PDF Document 45 KB)
Resource for clinicians to help confirm diagnosis; American College of Medical Genetics.

Very Long Chain Acyl-CoA Dehydrogenase Deficiency (VLCADD) (NECMP)
A guideline for health care professionals treating the sick infant or child with VLCADD; developed under the direction of Dr. Harvey Levy, Senior Associate in Medicine/Genetics at Children’s Hospital Boston, and Professor of Pediatrics at Harvard Medical School, for the New England Consortium of Metabolic Programs.

Services for Patients & Families Nationwide (NW)

Genetics clinic services throughout the US can be found through the Genetics Clinic Services Search Engine (ACMG).

For services not listed above, browse our Services categories or search our database.

* number of provider listings may vary by how states categorize services, whether providers are listed by organization or individual, how services are organized in the state, and other factors; Nationwide (NW) providers are generally limited to web-based services, provider locator services, and organizations that serve children from across the nation.


Very Long Chain Acyl-CoA Dehydrogenase Deficiency (birth-17 years) (ClinicalTrials.gov)
Studies looking at better understanding, diagnosing, and treating this condition; from the National Library of Medicine.

Authors & Reviewers

Initial publication: March 2007; last update/revision: December 2015
Current Authors and Reviewers:
Author: Nicola Longo, MD, Ph.D.

Page Bibliography

Ficicioglu C, Coughlin CR 2nd, Bennett MJ, Yudkoff M.
Very long-chain acyl-CoA dehydrogenase deficiency in a patient with normal newborn screening by tandem mass spectrometry.
J Pediatr. 2010;156(3):492-4. PubMed abstract

Therrell BL Jr, Lloyd-Puryear MA, Camp KM, Mann MY.
Inborn errors of metabolism identified via newborn screening: Ten-year incidence data and costs of nutritional interventions for research agenda planning.
Mol Genet Metab. 2014;113(1-2):14-26. PubMed abstract / Full Text