Medium-chain acyl-CoA dehydrogenase deficiency and sudden death in two siblings

Medium-chain acylCoA dehydrogenase (MCAD) deficiency is a disorder of fatty acid oxidation whose prevalence in North-Eastern Europe has been estimated at 1/10000 to 1/20000 births. MCAD deficiency can cause sudden death in th e first two years of life. Two cases in siblings are reported; both patient s died at nine months of age. Case report: A male infant, born to unrelated Caucasian parents, died suddenly at age 9 months during an episode of vira l gastroenteritis. Post mortem examination was non contributive, Twenty-one months later, his younger sib, aged 9 months, presented with apparently be nign gastroenteritis causing feeding problems. He was admitted several hour s later in a coma with severe hypoglycaemia and died shortly afterwards des pite ressuscitation. Autopsy showed prominent steatosis in the liver. The s tudy of urinary organic acids and acylcarnitines disclosed pathognomonic pr ofiles consistent with MCAD. The diagnosis was confirmed by DNA analysis sh owing the specific MCAD mutation G 985 A in a homozygous state in both sibl ings. The authors emphasize the value of MCAD routine screening in the newb orn population, by mutation analysis and/or by blood acylcarnitine profiles . Conclusion. Screening for MCAD is warranted in all infants presenting wit h severe malaise or unexplained sudden death.