Short-chain acyl-coenzyme A dehydrogenase deficiency

Signs and symptoms

Short-chain acyl-coenzyme A dehydrogenase deficiency affected infants will have vomiting, low blood sugar, a lack of energy (lethargy), poor feeding, and failure to gain weight and grow. Additional features of this disorder may include poor muscle tone (hypotonia), seizures, developmental delays, and microcephaly. The symptoms of short-chain acyl-CoA dehydrogenase deficiency may be triggered during illnesses such as viral infections. In some cases, signs and symptoms may not appear until adulthood, when some individuals may develop muscle weakness, while other individuals mild symptoms may never be diagnosed.

Genetics

SCADD is caused genetically by mutations in the ACADS gene, located on chromosome 12q22-qter. Mutations in the ACADS gene lead to inadequate levels of short-chain acyl-CoA dehydrogenase, which is important for breaking down short-chain fatty acids. Low levels of this enzyme halt short-chain fatty acids from being further broken down and processed in the mitochondria, consequently, these short-chain fatty acids are not converted into energy.

The disorder is inherited via autosomal recessive.

Diagnosis

The diagnosis of short-chain acyl-coenzyme A dehydrogenase deficiency is based on the following:

• Newborn screening test
• Genetic testing
• Urine test

Differential diagnosis

The differential diagnosis for short-chain acyl-coenzyme A dehydrogenase deficiency is: ethylmalonic encephalopathy, mitochondrial respiratory chain defects and multiple acyl-CoA dehydrogenase deficiency.

Treatment

In terms of treatment for this condition, short-chain acyl-CoA dehydrogenase deficiency, some individuals may not need treatment, while others might follow administration of:

• Riboflavin
• Dextrose
• Anticonvulsants

Epidemiology

This disorder, epidemiologically speaking, is thought to affect approximately 1 in 50,000 newborns according to Jethva, et al. While in the U.S. state of California there seems to be a ratio of 1 in 35,000.

References

References

1. {{OMIM. 201470
2. (Dec 2008). "Mini-Review: Short-Chain Acyl-Coenzyme A Dehydrogenase Deficiency". Molecular Genetics and Metabolism.
3. RESERVED, INSERM US14 -- ALL RIGHTS. "Orphanet: Short chain acyl CoA dehydrogenase deficiency".
4. "Short-chain acyl-CoA dehydrogenase deficiency {{!}} Genetic and Rare Diseases Information Center(GARD) – an NCATS Program".
5. {{OMIM. 606885
6. Reference, Genetics Home. "SCAD deficiency".
7. "Autosomal recessive: MedlinePlus Medical Encyclopedia". NIH.
8. "Newborn screening tests: MedlinePlus Medical Encyclopedia".
9. "Deficiency of butyryl-CoA dehydrogenase - Conditions - GTR - NCBI". NIH.
10. (1 January 1993). "Short-Chain Acyl-CoA Dehydrogenase Deficiency". GeneReviews.