No abstract

Intoxication by GHB has substantial morbidity and abuse of GHB has substantial mortality. The acute prognosis is good but long-term prognosis is insecure with an increased risk for drug dependency and an early death.

ABSTRACT. We report the finding of mitochondrial ATPsynthase deficiency in a child with persistent 3-methylglutaconic aciduria. The child presented in the neonatal period with severe lactic acidosis, which was controlled by Na-H C 0 3 and glucose infusions. During the 1st y of life, there were several episodes of lactic acidosis precipitated by infections or prolonged intervals between meals. The excretion of lactate in urine was variable, but there was a persistent high excretion of 3-methylglutaconic acid. The activity of 3-methylglutaconyl-CoA hydratase in fibroblasts was normal. The child had a hypertrophic cardiomyopathy and magnetic resonance images revealed hypoplasia of corpus callosum. The gross motor and mental development was retarded, but there were no other neurologic signs. Investigation of muscle mitochondrial function at 1 y of age revealed a severe mitochondrial ATP-synthase deficiency (oligomycin-sensitive, dinitrophenol-stimulated Mg2+ ATPase activity: 27 nmol x min-' x (mg protein)-', control range 223-673 nmol x min-' x (mg protein)-'.The mitochondrial respiratory rate was low and tightly coupled. The respiratory rate was normalized by the addition of an uncoupler. Low MgZ+ ATPase activity was also demonstrated by histochemical methods. Morphologic examination revealed ultrastructural abnormalities of mitochondria. There was no deletion of mitochondrial DNA. The sequences of the ATP synthase subunit genes of mitochondrial DNA were in accordance with published normal sequences. (Pediatr Res 32: 731-735,1992)

Vomiting, lethargy and metabolic acidosis were the main initial symptoms of metabolic disease in a 1 month old girl. Her older sister had died from a similar disease, considered to be Reye's syndrome, at an age of 15 months. The urine of the present case contained 2-methylcitric acid, 3-hydroxypropionic acid, N-propionylglycine, 2-hydroxy-3-methylbutyric acid, N-tiglylglycine, 3-hydroxyvaleric acid and glutaric acid. These metabolites are all known to be associated with propionyl-CoA accumulation. Free propionic acid was not detected in the urine. In addition, the urine contained 3-oxo-2-methylvaleric acid and 3-hydroxy-2-methylvaleric acid, probably formed by condensation of two molecules of propionyl-CoA. The identity of these metabolites was confirmed by synthesis. An elevated urinary concentration of maleic acid and fumaric acid was another constant abnormality. The activity of propionyl-CoA carboxylase in leucocytes was about 20% of the normal activity. The girl was teated with a low-protein diet since the diagnosis was made at an age of 1 month, and her psychomotor development was satisfactory at an age of 2 1/2 years. She had a few episodes of acidosis during infections.