Very long-chain acyl-CoA dehydrogenase deficiency presenting as acute hypercapnic respiratory failure

Abstract

Very long-chain acyl-CoA dehydrogenase deficiency (VLCAD) is a key enzyme catalysing the dehydrogenation of long-chain fatty acids in mitochondrial beta-oxidation. VLCAD deficiency is a genetic disorder that commonly presents in infancy or childhood with episodes of hypoketotic hypoglycaemia, cardiomyopathy and liver dysfunction. The present study reports an 18-yr-old Chinese female who presented with acute hypercapnic respiratory failure and rhabdomyolysis after a period of prolonged fasting and exertion. VLCAD deficiency was confirmed with decreased VLCAD activity in cultured fibroblasts. The patient completely recovered with supportive care. Pulmonary function tests after the acute episode showed evidence of chronic subclinical respiratory muscle weakness. In conclusion, this rare metabolic disorder should be considered in patients presenting with unexplained acute respiratory paralysis and failure.