[Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency in 2 patients with symptoms of Reye syndrome]

Two patients are described, who were submitted to our clinic with signs of the Reye syndrome. In both cases a medium-chain acylcoënzyme A dehydrogenase (MCAD) deficiency was diagnosed. This is an inborn error of the mitochondrial beta-oxidation of fatty acids. Stimulation of the fatty acid oxidation in case of this enzyme deficiency might result in a metabolic crisis presenting clinically as the Reye syndrome. The structure of a fatty acid molecule and the process of beta-oxidation of fatty acids are discussed shortly in this article. The most important clinical, diagnostic and therapeutic aspects of MCAD deficiency are presented next. A MCAD deficiency seems not to be rare in cases presenting as a Reye-like syndrome. Accurate distinction between MCAD deficiency and Reye syndrome can be made by gas chromatographic together with mass spectrometric analysis of urine. Investigation of so called crisis urine is of utmost importance. Confirmation of the diagnosis needs measuring of MCAD enzyme activity in cultured fibroblasts or in leucocytes of the patient.