title: Fatal lactic acidosis in infancy with a defect of complex III of the respiratory chain.
abstract: We report our studies on the metabolic defects which caused a newborn infant to present with a severe lactic acidemia (25 mM) and to die on the 3rd d after birth despite intensive supportive measures. The mitochondrial fractions prepared from skeletal muscle and liver oxidised NAD+-linked substrates and succinate slowly. Spectrophotometric assays for complexes I, II, and III of the respiratory chain demonstrate a specific defect of complex III in the skeletal muscle and liver mitochondrial fractions. The concentrations of cytochrome b were 75% lower in the skeletal muscle and heart mitochondria than in control preparations. The amount of non-heme iron sulphur protein of complex III was low in skeletal muscle, liver, and heart. This case differs from previous reports of complex III deficiency in three respects: the patient presented in the neonatal period, the defect was expressed in several tissues, and it was fatal.
authors.affiliation: Department of Neurology, University of Newcastle upon Tyne, U.K.
authors.forename: M A
authors.initials: MA
authors.lastname: Birch-Machin
authors.forename: I M
authors.initials: IM
authors.lastname: Shepherd
authors.forename: N J
authors.initials: NJ
authors.lastname: Watmough
authors.forename: H S
authors.initials: HS
authors.lastname: Sherratt
authors.forename: K
authors.initials: K
authors.lastname: Bartlett
authors.forename: V M
authors.initials: VM
authors.lastname: Darley-Usmar
authors.forename: D W
authors.initials: DW
authors.lastname: Milligan
authors.forename: R J
authors.initials: RJ
authors.lastname: Welch
authors.forename: A
authors.initials: A
authors.lastname: Aynsley-Green
authors.forename: D M
authors.initials: DM
authors.lastname: Turnbull
mesh_terms: D000140:Acidosis, Lactic / Q000209:etiology*; D003580:Cytochromes / Q000032:analysis; D004579:Electron Transport; D014450:Electron Transport Complex III / Q000032:analysis / Q000172:deficiency*; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D008297:Male; D008928:Mitochondria / Q000032:analysis*
chemical_list: D003580:Cytochromes; D014450:Electron Transport Complex III