Medium- and
short-chain acyl-CoA dehydrogenase deficiency is a disorder of
fatty acid β-oxidation. Gene mutation prevents medium- and
short-chain fatty acids from entry into mitochondria for oxidation, which leads to multiple organ dysfunction. In this study, serum acylcarnitines and the organic
acid profile in
urea were analyzed in two children whose clinical symptoms were
hypoglycemia and
metabolic acidosis. Moreover, gene mutations in the two children and their parents were evaluated. One of the patients was a 3-day-old male who was admitted to the hospital due to neonatal
asphyxia, sucking weakness, and
sleepiness. The serum
acylcarnitine profile showed increases in medium-chain acylcarnitines (C6-C10), particularly in C8, which showed a concentration of 3.52 μmol/L (reference value: 0.02-0.2 μmol/L). The analysis of organic
acids in
urea gave a normal result. Sanger sequencing revealed a reported c.580A>G (p.Asn194Asp) homozygous mutation at exon 7 of the ACADM gene. The other patient was a 3-month-old female who was admitted to the hospital due to
cough and recurrent
fever for around 10 days. The serum
acylcarnitine profile showed an increase in serum C4 level, which was 1.66 μmol/L (reference value: 0.06-0.6 μmol/L). The analysis of organic
acids in
urea showed an increase in the level of ethyl
malonic acid, which was 55.9 (reference value: 0-6.2). Sanger sequencing revealed a reported c.625G>A (p.Gly209Ser) homozygous mutation in the ACADS gene. This study indicates that screening tests for genetic
metabolic diseases are recommended for children who have unexplained
metabolic acidosis and
hypoglycemia. Genetic analyses of the ACADM and ACADS genes are helpful for the diagnosis of medium- and
short-chain acyl-CoA dehydrogenase deficiency.