Very Long-Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD)

What this deck covers

Very Long-Chain Acyl-CoA Dehydrogenase Deficiency (VLCAD) in fourteen clinical teaching cases with worked explanations. Each case gives you a clinical vignette, four options, the correct answer, and an explanation of why each of the other three is wrong.

Diagnoses and management options tested

Across the fourteen cases you are asked to choose between options such as: Severe early-onset cardiac and multiorgan failure, Hypoglycaemic phenotype, Cardiac arrhythmia syndrome, Late-onset episodic myopathy, Carnitine palmitoyltransferase II deficiency, Hepatic or hypoglycaemic form, Mitochondrial encephalopathy, Late-onset myopathic form, Metabolic acidosis due to lactic acidosis, Congenital heart defect, Generalised hypotonia with areflexia, Facial diplegia and ptosis, Distal muscle wasting with foot drop, Proximal muscle weakness with Gowers’ sign, Focal neurological deficit with asymmetric reflexes, Meningismus with a positive Kernig sign, Papilloedema with a bulging fontanelle, Altered mental status with decreased responsiveness, Deficiency of the VLCAD enzyme, Deficiency of the MCAD enzyme, Carnitine transporter defect, Deficiency of the CPT-I enzyme, Deficiency of mitochondrial ATP synthase, Excess ketone body production, Impaired gluconeogenesis in hepatocytes, C14:1 below 0.4 µmol/L.

Clinical pearls from this deck

• VLCAD has three phenotypes, and this is the late-onset myopathic form — recurrent muscle pain and rhabdomyolysis triggered by fever, fasting or prolonged exercise, with dark urine from myoglobinuria. Critically, there is no hypoglycaemia and no cardiac involvement.
• The hepatic or hypoglycaemic form presents in infancy to age 2 with hypoketotic hypoglycaemia, hepatomegaly and raised transaminases — and notably without cardiomyopathy or arrhythmia. It is now most often picked up on newborn screening before symptoms appear.

The fourteen worked cases in this deck, with the images and the full explanation of every option, are part of Pediatric Case Review membership. See what is included.

More from this system: all metabolic and genetic decks and question sets · pediatric reference values.