Introduction: Long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency (LCHADD) is a rare disease, inherited as autosomal-recessive trait, with variable clinical presentation including severe hypoglycaemia, cardiomyopathy, sudden infant death, progressive liver failure, 'Reye like' syndrome, neuromyopathy, muscle weakness and rhabdomyolysis.
Case report: We report a 3 years old male patient admitted to our emergency department with vomiting, hypotonia and prostration, after a common respiratory infection. The presence of hypoketotic hypoglycaemia and elevated liver enzymes in the admission motivated a metabolic study. We found an abnormal low lactate/pyruvate ratio, decreased serum carnitine and dicarboxylic aciduria leading to the diagnosis of a fatty acid oxidation disorder (LCHADD). The molecular study of HADHA gene revealed homozygosity for the G1528C mutation in the patient DNA, and heterozygosity in both parents.
Conclusions: The diagnosis of a fatty acid oxidation disorder must be considered in the presence of vomiting associated with excessive prostration specially if there is hypoketotic hypoglycaemia or familiar sudden infant death history. Physicians should be aware about these conditions and for the importance of measuring both glycaemia and ketone bodies during the evaluation of high risk situations.