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Query: UMLS:C0085584 (encephalopathy)
 18,178 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mixed disulfides of methanethiol represent a relative estimate for an exposure to methanethiol. The concentrations of methanethiol-mixed disulfides, methionine, 4-methylthio-2-oxobutyrate and ammonia were measured in patients with different stages of hepatic encephalopathy, in patients with chronic kidney failure and in healthy subjects. In patients with hepatic encephalopathy, the mean serum concentrations of all these compounds were elevated. However, the elevations of methanethiol-mixed disulfides were small and partly caused by decreased renal function. In addition, the levels of methanethiol-mixed disulfides did not differ significantly between the different grades of hepatic encephalopathy. The concentrations of methanethiol-mixed disulfides were substantially lower than those previously observed in healthy subjects after an oral methionine load or in a patient with a deficiency in methionine adenosyltransferase, the latter without causing encephalopathy. We concluded that the role of methanethiol in the pathogenesis of hepatic encephalopathy is probably minor, if not insignificant. In the patients with hepatic encephalopathy, a significant correlation was found between the concentrations of methionine and 4-methylthio-2-oxobutyrate and between 4-methylthio-2-oxobutyrate and methanethiol-mixed disulfides, supporting the theory that methanethiol is formed by way of the methionine transamination pathway. Evidence is provided that, besides the methionine transsulfuration pathway, the transamination pathway is also impaired in patients with hepatic encephalopathy.
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PMID:The role of methanethiol in the pathogenesis of hepatic encephalopathy. 199 15

Arterial ketone body ratio (AKBR [acetoacetate/beta-hydroxybutyrate]) was measured in nineteen patients under medical supportive therapy for fulminant hepatic failure (FHF), in order to evaluate its predictive value relative to liver transplantation. Of the 19 patients 8 (42%) were salvaged and 11 (58%) died. Seven of 8 survivors showed an increased AKBR over 0.6 at 24-hr after admission, and all of them showed AKBR over 0.8 at 48-hr with subsequent maintenance of the value over 1.0. By contrast, all 11 nonsurvivors demonstrated sustained suppression of AKBR below 0.4 from 24 to 72 hr after admission. AKBR values at 24 and 48 hr showed statistically significant differences between survivors and nonsurvivors. Neither the grade of portal systemic encephalopathy (PSE) nor other conventional laboratory parameters--such as AST, bilirubin, ammonia, prothrombin time, hepaplastin test, fibrinogen, and platelet count--could discriminate between survivors and nonsurvivors by univariate analysis. These results indicate that AKBR can accurately predict the prognosis of FHF at the initial 24-48 hr after admission, and that it can play an important role in setting the indication of FHF for liver transplantation.
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PMID:Arterial ketone body ratio as a possible indicator for liver transplantation in fulminant hepatic failure. 201 30

Hyperammonaemia in the urological patient is a rare and potentially grave condition. It has been reported most frequently in association with ureterosigmoidostomy, where clinical neurological symptoms have developed abruptly in association with markedly elevated plasma ammonia levels. The purpose of this study was to determine whether ureterosigmoidostomy patients might have subclinically elevated plasma ammonia levels, which would put them at risk of subsequently developing hyperammonaemic encephalopathy. Both urine and plasma ammonia levels were assayed in 10 asymptomatic paediatric urological patients with ureterosigmoidostomy. Ten paediatric colocystoplasty patients served as controls. Urine pH and urine ammonia levels were significantly higher in the ureterosigmoidostomy group. There was no significant difference in plasma ammonia levels between ureterosigmoidostomy and colocystoplasty patients. In none of the patients was the plasma ammonia level elevated, but 1 ureterosigmoidostomy patient had an exceedingly high urine ammonia level. It was concluded that an annual serum ammonia level in an asymptomatic ureterosigmoidostomy patient is probably not a valuable screen for subclinical hyperammonaemia.
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PMID:Ammonia levels in paediatric ureterosigmoidostomy patients: a screen for hyperammonaemia? 203 25

Plasmapheresis is used for treating the complications of liver failure. We performed plasmapheresis on 6 children with hepatic encephalopathy resulting from acute hepatic failure and prospectively assessed its effects on neurologic and electrophysiologic (electroencephalography and evoked potentials) function. Clinical improvement was observed in 3 of 6 patients; changes in the serum ammonia value or the results of initial electrophysiologic tests did not predict the patient response. Two patients underwent transplantation after neurologic improvement was produced by plasmapheresis; however, despite plasmapheresis, 4 patients progressed to brain death. Our data demonstrate that plasmapheresis may transiently improve the encephalopathy of acute hepatic failure but is not curative alone. Therefore, plasmapheresis may be a useful adjunct in the treatment of liver failure, potentially improving the pretransplantation status of the patient.
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PMID:Value of plasmapheresis in hepatic encephalopathy. 207 1

One year prospective study of 25 cirrhotic patients with portal systemic encephalopathy (PSE) admitted to the Emergency Care Centre in Belgrade was performed in order to investigate the significance of clinical, biochemical and electroencephalographic (EEG) parameters and blood ammonia in the diagnosis, differential diagnosis and prognosis of PSE. 15 cirrhotic patients without PSE (of comparable age, sex, duration and etiology of liver cirrhosis) constituted the control group. Ammonia levels were elevated in 84% of patients with PSE (112 +/- 72 mumol/l) and reached normal range within 3 +/- 0.44 days, but with no correlation to clinical improvement (p greater than 0.1). Ammonia levels correlated with the severity of PSE (p less than 0.05), but not with other biochemical parameters (prothrombin time, bilirubin, albumin, urea, creatinine, potassium). Overall mortality was 44% and was strongly correlated (p less than 0.01) to the severity of PSE. In addition, the mortality in patients with gastrointestinal bleeding and PSE was higher (p less than 0.05), than in PSE precipitated by other conditions. We concluded that the ammonia may be a primary diagnostic parameter for PSE in the absence of the most important diagnostical methods (EEG, psychometric tests). Secondly, ammonia are of great diagnostic importance in patients with coma of unknown origin and can help in deciding admission priorities. The ammonia levels do not appear to be a useful prognostic factor.
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PMID:[Ammoniemia in portosystemic encephalopathy--diagnostic, differential diagnostic and prognostic significance]. 207 39

Nutritional support in patients with advanced cirrhosis is difficult due to protein, fluid and salt restrictions. Successful liver transplantation should improve nutrient tolerance. We randomly assigned 28 hypoalbuminemic cirrhotic patients to receive, immediately after liver transplantation, one of three regimens: group 1, no nutritional support (n = 10); group 2, total parenteral nutrition (TPN) (35 kcal/kg/day) with standard amino acids (1.5 g/kg/day) (n = 8); or group 3, isocaloric isonitrogenous TPN with added branched-chain amino acids (n = 10). Therapy was continued for 7 days posttransplant. Jaundice resolution was unaffected by nutritional support. Nitrogen balance favored both TPN groups. Branched-chain amino acid (BCAA) aromatic amino acid ratios were highest in group 3. Coma scores and serum ammonia levels were similar in all groups. Both TPN groups achieved respirator independence earlier; this difference was not statistically significant. Group 1 patients stayed longest in ICU; the difference was statistically significant. TPN with either standard or BCAA- enriched amino acids is tolerated well immediately after successful liver transplant. Positive nitrogen balance is achieved; large protein loads do not worsen encephalopathy. Nutritional support may improve respiratory muscle function, allowing earlier weaning from ventilatory support. A shortened length of ICU stay justifies the expense of TPN.
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PMID:Nutritional support after liver transplantation: a randomized prospective study. 179 69

Quantitative autoradiography was used to assess the densities of gamma-aminobutyric acid (GABAA) receptors in the brains of rats with a portacaval end-to-side shunt (PCA). The shunt alone induced only mild encephalopathy with ataxia and decreased locomotion. Aggravation of the encephalopathy was achieved by gavage feeding of packed erythrocytes or by induction of severe hyperammonemia by intraperitoneal injection of urease. Gavage feeding of erythrocytes led to severe encephalopathy in about 50% of the animals with PCA. The combination of PCA and urease treatment caused severe encephalopathy in every animal. The serum ammonia concentration increased 5 times normal by PCA alone, 20 times normal by gavage feeding of erythrocytes and more than 30 times normal by urease-treatment of the PCA-animals. For autoradiography, coronal slices were cut at the level of the hippocampal formation and through the cerebellum. Radioligand binding was measured using as a ligand 3H-muscimol, a specific GABAA receptor agonist. The specific binding of 3H-muscimol was assessed densitometrically in several microregions of cerebral cortex, hippocampus and cerebellar cortex. No significant differences were observed between the magnitude of ligand binding to specific microregions of brains from normal animals, animals with PCA without overt encephalopathy and animals with severe encephalopathy induced by a combination of PCA and gavage feeding of erythrocytes or urease treatment.
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PMID:[Autoradiography determination of the GABA(A) receptor density in the brain of rats with portacaval shunt]. 216 Jul 60

Vancomycin hydrochloride (2 g daily) was administered to 12 patients with cirrhosis and lactulose resistant portal systemic encephalopathy in a double blind crossover trial. All 12 patients showed a remarkable clinical improvement after vancomycin treatment. The mean (SE) electroencephalographic (EEG) frequency changed from 6.3 (0.2) to 8.5 (0.2) cps (p less than 0.001) and the mean arterial ammonia concentration from 152 (4) micrograms/ml to 97 (8) micrograms/ml (p less than 0.001). Their clinical condition deteriorated when treatment was switched to lactulose, returning to the previous slower EEG frequency and high arterial ammonia concentrations. Vancomycin seems to be effective in chronic portal systemic encephalopathy in patients who are not helped by lactulose alone.
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PMID:Successful use of vancomycin hydrochloride in the treatment of lactulose resistant chronic hepatic encephalopathy. 226 94

Previous studies have suggested that the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) is a key factor in the syndrome of portasystemic encephalopathy. We report the case of a patient with medically intractable portasytemic encephalopathy after portacaval shunt who had marked clinical improvement after creation of an end ileostomy. Plasma GABA and serum ammonia levels were measured before and after ileostomy. Although the clinical syndrome and the EEG improved markedly after the ileostomy, the plasma GABA levels remained markedly elevated. Preoperative and postoperative GABA levels were 865 and 633 pmol/ml, respectively (nl = 100-180 pmol/ml). Our findings confirm previous reports of the efficacy of colonic exclusion in patients with intractable portasystemic encephalopathy. However, our results conflict with the hypothesis that GABA itself is the key mediator of the syndrome.
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PMID:Reversal of chronic hepatic encephalopathy by colonic exclusion: poor correlation with blood GABA levels. 225 33

Effects of differentiated diet with reduced proteins or diet without proteins with simultaneous use of lactulose or the preparation enriched with aliphatic amino acids with aminosteril-hepa chain on the clinical results and the ammonia, phenols, alpha-amino nitrogen, tyrosine, phenylalanine and tryptophan++ concentrations in the serum have been studied. It has been demonstrated that limitations of proteins in the diet or diet without proteins with the use of lactulose or amino acids mixtures above does not influence significantly the clinical amelioration or biochemical indices of encephalopathy or coma during the liver cirrhosis course. Homogenates of the liver and brain of patients who died due to encephalopathy and liver cirrhosis showed high contents of ammonia, tyrosine, phenylalanine and tryptophan++.
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PMID:[Effect of differentiated diet therapy on the clinical results and biochemical indicators in chronic hepatic encephalopathy]. 228 19


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