Short-Chain Acyl-CoA Dehydrogenase Deficiency (SCADD)

Guidance for primary care clinicians receiving a positive newborn screen result

Other Names

Acyl-CoA dehydrogenase short chain (ACADS)

ICD-10 Coding

E71.312, Short-chain acyl-CoA dehydrogenase deficiency

Disorder Category

A fatty acid oxidation disorder

Screening

Abnormal Finding

Elevated C4 (butyrylcarnitine)

Tested By

Tandem mass spectrometry (MS/MS); sensitivity=100%; specificity=99.99% [Schulze: 2003]

Description

During prolonged fasting and increased energy demands (fever, stress, vomiting, diarrhea), energy production increasingly relies on fat metabolism. Because short-chain acyl-CoA dehydrogenase deficiency (SCADD) (the result of an intramitochondrial defect in the beta-oxidation of fatty acids) may impair this form of energy production, metabolic crisis may result. However, for not yet understood reasons, most children with SCADD never have symptoms and are usually healthy. This condition usually requires no treatment.

Clinical Characteristics

The impact of treatment is unknown. Most patients identified by newborn screening will be asymptomatic; however, some affected infants may present with:
  • Vomiting
  • Lethargy
  • Seizures
  • Hypoketotic hypoglycemia
Subsequent symptoms may occur including:
  • Failure to thrive
  • Muscle weakness
  • Developmental delay
  • Seizures
  • Metabolic acidosis
An adult form of SCADD affects only the muscles and may cause:
  • Pain and weakness, especially after exertion
  • Episodes of nausea, vomiting, and shortness of breath
The relationship of the above symptoms to SCADD is not clear, and in some cases, other causes have been identified. Milder variants of this condition are very frequent in the general population and usually do not require treatment. Even severe forms usually cause no symptoms even though they might aggravate co-existing conditions. Treatment consists of carnitine supplementation, a low-fat diet, and fasting avoidance. Again, this is rarely needed.

Incidence

1:83,300 [Schulze: 2003]

Inheritance

Autosomal recessive

Primary Care Management

Next Steps After a Positive Screen

  • Contact the family and evaluate the infant for poor feeding, vomiting, and lethargy.
  • Provide emergency treatment/referral for signs or symptoms of hypoglycemia, lethargy, and metabolic acidosis.

Confirming the Diagnosis

  • To confirm the diagnosis, work with Newborn Screening Services (see ID providers [22]).
  • Follow-up testing usually involves a quantitative plasma acylcarnitine profile, urine organic acids (increased ethylmalonic acid), and urine acylglycine analysis. SCADD must be differentiated from other causes of elevated C4, such as ethylmalonic encephalopathy, which is a much more serious condition, and isobutyrylglycinuria, a very rare condition associated in 1 case with cardiomyopathy.

If the Diagnosis is Confirmed

Resources

Information & Support

After a Diagnosis or Problem is Identified
Families can face a big change when their baby tests positive for a newborn condition. Find information about A New Diagnosis - You Are Not Alone; Caring for Children with Special Health Care Needs; Assistance in Choosing Providers; Partnering with Healthcare Providers; Top Ten Things to Do After a Diagnosis.

For Professionals

Short-Chain Acyl-CoA Dehydrogenase Deficiency (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.

Short-Chain Acyl-CoA Dehydrogenase Deficiency (OMIM)
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

Short-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.

Short-Chain Acyl-CoA Dehydrogenase Deficiency - 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 this newborn disorder; Screening, Technology and Research in Genetics.

Baby's First Test: SCADD (Genetic Alliance)
Information about early signs, follow-up testing, treatment, accessing care, and expected outcomes. Provides links to support services.

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

Tools

Confirmatory Algorithm for SCADD/Elevated C4 (ACMG) (PDF Document 202 KB)
Contains short-term recommendations for clinical follow-up of the newborn who has screened positive; American College of Medical Genetics.

Services for Patients & Families in Idaho (ID)

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.

Helpful Articles

PubMed search for short-chain acyl-CoA dehydrogenase deficiency in children

Viscomi C, Burlina AB, Dweikat I, Savoiardo M, Lamperti C, Hildebrandt T, Tiranti V, Zeviani M.
Combined treatment with oral metronidazole and N-acetylcysteine is effective in ethylmalonic encephalopathy.
Nat Med. 2010;16(8):869-71. PubMed abstract / Full Text
Dual treatment of oral metronidazole and N-acetylcysteine caused marked clinical improvement in five affected children, with hardly any adverse or side effects.

Authors & Reviewers

Initial publication: March 2007; last update/revision: July 2017
Current Authors and Reviewers:
Author: Nicola Longo, MD, Ph.D.
Authoring history
2011: first version: Nicola Longo, MD, Ph.D.A
AAuthor; CAContributing Author; SASenior Author; RReviewer

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