Unexpected neonatal death due to medium-chain acyl-CoA deficiency

Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is the most common fatty acid oxidation disorder, with an incidence of 1:19,000 live births in Australia.1 The typical presentation MCADD between 3 and 24 months age include hypoglycaemia, hepatomegaly sudden death.2 Our case a full term well grown male baby who was born good condition. He became lethargic had long periods without feeds on day 2 life. On life, he developed tachypnoea grunting admitted to Neonatal Intensive Care Unit at Royal Children’s Hospital. found have hypothermia, hypoglycaemia metabolic acidosis. continued deteriorate died 4 days age. newborn dried blood spot (DBS) test result pending presumed cause death sepsis. A autopsy revealed widespread hepatic microvesicular steatosis cytoplasmic vacuolation renal tubular epithelium, suggestive condition such as disorder oxidation.3 Analysis DBS showed elevated C8 carnitine 22.4μmol/L (<0.45μmol/L), C10 2.67μmol/L (<0.57μmol/L) C8/C10 ratio 8.38μmole/μmole (<2.5μmole/μmole), confirming diagnosis MCADD. References 1. Wilcken B, Haas M, Joy P, et al. Expanded screening: outcome screened unscreened patients 6 years. Pediatrics 2009; 124: e241–8. 2. Merritt JL 2nd, Chang IJ. acyl-coenzyme deficiency. 2000 Apr 20 [updated 2019 Jun 27]. In: Adam MP, Everman DB, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University Washington, Seattle; 1993–2022. PMID: 20301597. 3. Editorial. Sudden infant inherited disorders fat oxidation. Lancet 1986; 2: 1073–5.