Delayed diagnosis of fatal medium-chain acyl-CoA dehydrogenase deficiency in a child
A K Shetty1, R D Craver, J A Harris
1Department of Pediatrics, Louisiana State University Medical Center, New Orleans 70112, USA.
Insights
Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency can cause sudden death in children. Early diagnosis is crucial for fatty acid oxidation disorders presenting with hypoglycemia and metabolic acidosis.
Area of Science:
- Biochemistry
- Genetics
- Pediatrics
Background:
- Inborn errors of metabolism are a group of genetic disorders that affect the body's ability to metabolize nutrients.
- Fatty acid oxidation disorders are a subset of inborn errors of metabolism that impair the body's ability to break down fats for energy.
Observation:
- A 5-year-old female presented with coma and subsequent death.
- She had a history of recurrent febrile illnesses with lethargy and coma.
- Postmortem examination revealed fatty liver, raising suspicion of a fatty acid oxidation disorder.
Findings:
- Abnormal acylcarnitine profile with elevated octanoylcarnitine suggested medium-chain acyl-CoA dehydrogenase (MCAD) deficiency.
- Fatty acid oxidation studies and mutation analysis confirmed the diagnosis of MCAD deficiency.
- MCAD deficiency is an autosomal recessive genetic disorder affecting fatty acid metabolism.
Implications:
- This case highlights the importance of considering fatty acid oxidation disorders in pediatric patients with unexplained hypoglycemia, particularly when accompanied by mild or absent ketosis and high anion gap metabolic acidosis.
- Timely diagnosis and management of MCAD deficiency can prevent severe complications and mortality.
- Genetic counseling and carrier screening may be beneficial for families with a history of MCAD deficiency.
Abstract:
A 5-year-old white female presented with coma and died unexpectedly. She had a history of recurrent episodes of febrile illnesses associated with lethargy and coma. Postmortem investigation revealed a fatty liver, leading to a suspicion of inborn error of fatty acid oxidation. The diagnosis of medium-chain acyl-CoA dehydrogenase (MCAD) deficiency was suggested by abnormal acylcarnitine profile with increased octanoylcarnitine in the blood, and confirmed by fatty acid oxidation studies and mutation analysis in skin fibroblast cultures. This case emphasizes the need to consider fatty acid oxidation disorders in all children who present with hypoglycemia with absent or mild ketones in the urine and high anion gap metabolic acidosis.
