Subacute necrotizing encephalomyelopathy. Effects of thiamine and thiamine propyl disulfide

Leigh syndrome, a mitochondrial encephalo(myo)pathy. A review of the literature

Results of a literature survey of 173 patients with Leigh syndrome are presented, with emphasis on signs and symptoms in relation to age at onset, contributions of technical investigations to the diagnosis, pathophysiology, genetic considerations and therapeutic aspects. Based on this study we are of the opinion that it is possible to come to a diagnosis of "most probable Leigh syndrome" durante vitamin on the combination of clinical signs and symptoms, autosomal recessive mode of inheritance, association with a defect of energy metabolism, and CT or MRI abnormalities.

Chronic Leigh Disease: a genetic and biochemical study

The large family of a 21-year-old man who died of Leigh disease was investigated for evidence of neurological abnormalities and presence of the adenosine triphosphate-thiamine diphosphate phosphoryltransferase inhibitor factor. Of 217 persons (seven generations) included in the pedigree, 68 were examined neurologically and biochemically. Fourteen (20%), 5 of whom had abnormal neurological findings, were found to excrete the inhibitor factor. Clinical manifestations varied from severe neurological affliction to subtle deficits. A chronic relapsing course was frequently encountered, with exacerbations occurring in association with apparent metabolic stress. Parental consanguinity was identified in the propositus as well as in other family members with neurological abnormalities. Males and females were affected, and no vertical transmission of the trait was found. These multigenerational data suggest that Leigh disease in adults is inherited in an autosomal recessive manner and has variable degrees of expression with a wide spectrum of neurological manifestations.

Familial subacute necrotizing encephalomyelopathy of the adult form (adult Leigh syndrome)

A family--mother and 2 sons--with a heredodegenerative neurological disease is described. The disease started with bilateral optic atrophy, central scotoma, and color blindness during the second decade. This was followed by a quiescent period until additional neurological symptoms appeared, around the age of 50 years in the case of the mother and 40 and 30 years, respectively, in the sons. The additional symptoms were ataxia, spastic paresis, clonic jerks, grand mal seizures, psychia lability, and slight dementia. The disease was progressive, resulting in permanent hospitalization within a few years. The mother died at the age of 63 years and the sons at 46 and 43 years of age. Neuropathological examination revealed lesions histopathologically characteristic of subacute necrotizing encephalomyelopathy (SNE, Leigh disease), and their distribution in the brain and brainstem also conformed to this disease. On the basis of the clinical course and neuropathological findings, we consider that these 3 patients represent the first reported familial cases of the adult form of SNE.

Thiamine whole blood pharmackinetics in rats using both a specific S-thiamine liquid scintillation assay and the thiochrome fluorescence assay

The study of factors altering the CNS and GI absorption of thiamine in rats required the development of a specific assay for thiamine from 100-microliter samples of blood and plasma and small quantities of tissue. The specific thiochrome fluorescence assay for thiamine was modified to handle microsamples and to use S-thiamine. This sensitive and specific radioassay using S-thiamine gave pharmacokinetic parameters for 4-mg/kg iv doses of thiamine in rats equivalent to those using the less sensitive thiochrome fluorescence assay. The new assay, because of its lower limit of detection, allowed the study of the time profile of thiamine after a 1-mg/kg iv dose in rats. Such a time profile could not have been followed using the standard thiochrome fluorescence assay.

CT scan appearances in Leigh's disease (subacute necrotizing encephalomyelopathy)

Four cases of Leigh's disease (subacute necrotizing encephalomyelopathy), two confirmed at postmortem examination, have been investigated recently by CT scanning. All four showed the same symmetrical areas of low attenuation in the basal ganglia, especially the putamina. These areas corresponded with the typical areas of necrosis seen in this disease. There was also some evidence of atrophic change in the posterior fossa in some cases. This CT scan appearance may be diagnostic in the appropriate clinical context.

Hyperalaninemia hyperpyruvicemia and lactic acidosis due to pyruvate carboxylase deficiency of the liver; treatment with thiamine and lipoic acid

A 16-month-old female infant with severe mental and motor retardation, clinically diagnosed as Leigh's encephalomyelopathy, forms the basis of this study. This infant was found to have lactic acidosis, low cerebrospinal fluid glucose, hyperalaninemia, and increased levels of urine lactate, pyruvate and alanine. These laboratory studies suggested an inborn error in gluconeogenesis. Further investigation revealed a low level of hepatic pyruvate carboxylase activity. The patient's elder sister who also had mental and motor deterioration was then also found to have an elevated blood lactate. These two siblings clinically and biochemically showed improvement with treatment consisting of thiamine and lipoic acid.

Subacute necrotizing encephalomyelopathy. Clinical, ultrastructural, biochemical and therapeutic studies in an infant

Subacute necrotizing encephalomyelopathy (SNE) has been observed in an infant with regressing psychomotor development. The concentrations of alanine, pyruvate and lactate were increased in the serum and blood as well as in the cerebrospinal fluid. Pyruvate carboxylase activity was reduced in the liver tissue. An inhibitor of thiamine-pyrophosphate-ATP-phosphotransferase was present in the urine. Thiamine treatment was followed by a decrease of serum alanine and blood pyruvate and lactate, but there was no clinical improvement during a period of 17 months. Ultrastructural investigations revealed high glycogen levels in liver tissue and skeletal muscle. These findings contrast with decreased gluconeogenesis, which is suggested by the diminished pyruvate carboxylase activity. Therefore it is concluded that reduced hepatic pyruvate carboxylase activity is not the primary cause of SNE.