Metabolic autopsy with next generation sequencing in sudden unexpected death in infancy: Postmortem diagnosis of fatty acid oxidation disorders

•This is the first metabolic autopsy performed with next generation sequencing (NGS).•We detected one case of CPT II deficiency and three cases of FAOD-related rare variants.•Some of them had no specific abnormality except for genetic variants.•These cases would be undetected without NGS.•We advocate metabolic autopsy performed with NGS.

The recent introduction of metabolic autopsy in the field of forensic science has made it possible to detect hidden inherited metabolic diseases. Since the next generation sequencing (NGS) has recently become available for use in postmortem examinations, we used NGS to perform metabolic autopsy in 15 sudden unexpected death in infancy cases. Diagnostic results revealed a case of carnitine palmitoyltransferase II deficiency and some cases of fatty acid oxidation-related gene variants. Metabolic autopsy performed with NGS is a useful method, especially when postmortem biochemical testing is not available.