title: Inborn errors of ketone body utilization.
abstract: Succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency and mitochondrial acetoacetyl-CoA thiolase (beta-ketothiolase or T2) deficiency are classified as autosomal recessive disorders of ketone body utilization characterized by intermittent ketoacidosis. Patients with mutations retaining no residual activity on analysis of expression of mutant cDNA are designated as severe genotype, and patients with at least one mutation retaining significant residual activity, as mild genotype. Permanent ketosis is a pathognomonic characteristic of SCOT-deficient patients with severe genotype. Patients with mild genotype, however, may not have permanent ketosis, although they may develop severe ketoacidotic episodes similar to patients with severe genotype. Permanent ketosis has not been reported in T2 deficiency. In T2-deficient patients with severe genotype, biochemical diagnosis is done on urinary organic acid analysis and blood acylcarnitine analysis to observe characteristic findings during both ketoacidosis and non-episodic conditions. In Japan, however, it was found that T2-deficient patients with mild genotype are common, and typical profiles were not identified on these analyses. Based on a clinical study of ketone body utilization disorders both in Japan and worldwide, we have developed guidelines for disease diagnosis and treatment. These diseases are treatable by avoiding fasting and by providing early infusion of glucose, which enable the patients to grow without sequelae.
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Gifu University, Gifu, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Hori
authors.forename: Seiji
authors.initials: S
authors.lastname: Yamaguchi
authors.forename: Haruo
authors.initials: H
authors.lastname: Shinkaku
authors.forename: Reiko
authors.initials: R
authors.lastname: Horikawa
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Shigematsu
authors.forename: Masaki
authors.initials: M
authors.lastname: Takayanagi
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fukao
mesh_terms: D000138:Acidosis / Q000151:congenital / Q000235:genetics / Q000378:metabolism; D015256:Coenzyme A-Transferases / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007231:Infant, Newborn; D007657:Ketone Bodies / Q000378:metabolism*; D008661:Metabolism, Inborn Errors; D009154:Mutation
chemical_list: D018076:DNA, Complementary; D007657:Ketone Bodies; D015256:Coenzyme A-Transferases
keywords: inborn errors of ketone body utilization; ketone body; ketone body metabolism; mitochondrial acetoacetyl-CoA thiolase (beta-ketothiolase/T2) deficiency; succinyl-CoA:3-ketoacid CoA transferase (SCOT) deficiency