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

Cerebral edema and hepatic encephalopathy are major complications of acute liver failure. Brain herniation caused by increased intracranial pressure as a result of cell swelling is the major cause of death in this condition. Evidence available currently suggests that the rapid accumulation of ammonia by the brain is the major cause of the central nervous system complications of acute liver failure. Increased brain ammonia may cause cell swelling via the osmotic effects of an increase in astrocytic glutamine concentrations or by inhibition of glutamate removal from brain extracellular space. Acute liver failure results in altered expression of several genes in brain, some of which code for important proteins involved in CNS function such as the glucose (GLUT-1) and glutamate (GLT-1) transporters, the astrocytic structural protein glial fibrillary acidic protein (GFAP) the "peripheral-type" benzodiazepine receptor (PTBR) and the water channel protein, aquaporin IV. Loss of expression of GLT-1 results in increased extracellular brain glutamate in acute liver failure. Experimental acute liver failure also results in post-translational modifications of the serotonin and noradrenaline transporters resulting in increased extracellular concentrations of these monoamines. Therapeutic measures currently used to prevent and treat brain edema and encephalopathy in patients with acute liver failure include mild hypothermia and the ammonia-lowering agent L-ornithine-L-aspartate.
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PMID:Alterations in expression of genes coding for key astrocytic proteins in acute liver failure. 1174 25

The brain MR imaging characteristics of three patients with acute hyperammonemic encephalopathy resulting from late-onset ornithine transcarbomylase deficiency are presented. MR images revealed injury to the cortex, especially the cingulate gyrus and insular cortex, with sparing of the perirolandic and occipital cortices. These findings presumably reflect the distribution of brain injury from hypoperfusion secondary to hyperammonemia. Knowledge of the MR findings may help expedite diagnosis and treatment and prevent chronic impairment.
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PMID:Brain MR imaging in acute hyperammonemic encephalopathy arising from late-onset ornithine transcarbamylase deficiency. 1263 87

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome in patients with liver failure and/or a portal-systemic bypass. Since 2002 a new nomenclature of HE exists, that classifies HE in encephalopathy type A (associated with acute liver failure), type B (associated with portal-systemic bypass), and type C (associated with liver cirrhosis). HE type A is characterized by a rapid development to coma, cerebral edema, and a poor short-term prognosis. Therefore, these patients should be referred to a liver transplantation center. Standard treatment of HE consists of non absorbable disaccharides, non absorbable antibiotics, and a diet with an appropriate amount of proteins. In addition, the possibility of performing a liver transplantation should be evaluated. In patients with intractable HE other alternative treatments adjunct to standard treatment, like zinc, sodium benzoate, ornithine aspartate, branched chain amino acids, flumazenil, and bromocriptine should be considered.
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PMID:Hepatic encephalopathy: nomenclature, pathogenesis and treatment. 1276 Jul 20

Hepatic encephalopathy (HE) is a neuropsychiatric complication of acute and chronic liver failure. Its clinical spectrum ranges from minimal (subclinical) to overt encephalopathy. Psychometric and electrophysiological tests are helpful in diagnosing minimal HE. However, changes in metabolites in the brain, such as depletion of myo-inositol and accumulation of glutamine, appear to be very sensitive and specific in diagnosing this form. Positron emission tomography has been useful in studying brain ammonia metabolism. The main focus of medical treatment has been to modify ammonia metabolism. Reduction in ammonia production can be achieved by, among others, a diet rich in vegetable protein and carbohydrate, and oral lactulose, oral antibiotics and sodium benzoate. L-ornithine-L-aspartate provides critical substrates for both ureagenesis and glutamine synthesis, the key pathways for ammonia detoxification. Recent trials have shown its effectiveness in the treatment of HE.
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PMID:Hepatic encephalopathy syndromes. 1502 44

The urea cycle consists of six consecutive enzymatic reactions that convert waste nitrogen into urea. Urea cycle disorders are a group of inborn errors of hepatic metabolism that often result in life threatening hyperammonemia and hyperglutaminemia. Deficiencies of all of the enzymes of the cycle have been described and although each specific disorder results in the accumulation of different precursors, hyperammonemia and hyperglutaminemia are common biochemical hallmarks of these disorders. Arginase is the enzyme involved in the last step of the urea cycle. It catalyzes the conversion of arginine to urea and ornithine. The latter reenters the mitochondrion to continue the cycle. Hyperargininemia is an autosomal recessive disorder caused by a defect in the arginase I enzyme. Unlike other urea cycle disorders, this condition is not generally associated with a hyperammonemic encephalopathy in the neonatal period. It typically presents later in childhood between 2 and 4 years of age with predominantly neurological features. If untreated, it progresses with gradual developmental regression. A favorable outcome can be achieved if dietary treatment and alternative pathway therapy are instituted early in the disease course. With this approach, further neurological deterioration is prevented and partial recovery of skills ensues. Early diagnosis of this disorder through newborn screening programs may lead to a better outcome. This review article summarizes the clinical characterization of this disorder; as well as its biochemical, enzymatic, and molecular features. Treatment, prenatal diagnosis and diagnosis through newborn screening are also discussed.
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PMID:Clinical, biochemical, and molecular spectrum of hyperargininemia due to arginase I deficiency. 1660 94

Despite steady progress in therapeutics of liver disease, portal systemic encephalopathy remains to be a great challenge for clinicians because of the heterogeneity of neuropsychiatric symptoms, multiple risk factors and complexity on achieving a sustained response. We aimed to evaluate the efficacy of L-Ornithin, L-Aspartate versus lactulose in Mexican patients with hyperammonemic hepatic encephalopathy. A total of 20 patients were randomly allocated to receive either lactulose(n = 10) or L-ornithine - L-aspartate (n = 10) for 2 weeks. At baseline, patients of both groups were comparable in age (64 +/- 7 versus 60 +/- 6) and degree of hepatic failure according to the Child-Pugh scale (9.2 +/- 1.3 versus 9.2 +/- 1.1). A significant decrease in ammonia levels was observed both in the lactulose group (120.4 +/- 8.1 versus 91.4 +/- 10, p < 0.05) and in the LOLA group (141.6 +/- 9.1 versus 96.9 +/- 9.3, p < 0.05). Moreover, in patients who received LOLA a significant improvement was observed in mental status (1.0 +/- 0.14 versus 0.4 +/- 0.16, p < 0.05), Number Connection Test (184 +/- 43 versus 88 +/- 7, p < 0.05), asterixis (14.6 +/- 2.8 versus 6.7 +/- 1.5, p < 0.05), as well as EEG findings (6.8 +/- 0.6 versus 8.1 +/- 0.2 cycles per second, p < 0.05). Compliance with study medications was similar between the lactulose group (94%) and the LOLA group (100%). No serious adverse events were reported in the two groups; however, in the lactulose group an increase in the number of weekly defecations was reported, as well as a higher incidence of abdominal pain or flatulence. Finally, both patient groups reported an improvement in the Visual Analogue Scale for EuroQol index (51.1 +/- 24.1 versus 61.5 +/- 15.8, p < 0.05, in the lactulose group; 56.5 +/- 24.5 versus 70 +/- 19.4, p < 0.05, in the LOLA group). In conclusion, oral administration of lactulose or L-ornithine - L-aspartate to Mexican patients with cirrhosis and hyperammonemic encephalopathy significantly reduced serum ammonia levels in study groups and additionally improved mental status parameters, number connection test, asterixis scores, and EEG activity in the group receiving L-ornithine-L-aspartate.
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PMID:Efficacy of oral L-ornithine-L-aspartate in cirrhotic patients with hyperammonemic hepatic encephalopathy. Results of a randomized, lactulose-controlled study. 1715 82

A young patient with hepatocellular carcinoma receiving chemotherapy presented with encephalopathy. Evaluation of the patient revealed a metabolic profile consistent with ornithine transcarbamoylase (OTC) deficiency, an inherited disorder of the urea cycle. The evaluation yielded a plasma amino acid analysis consistent with OTC deficiency. However, genetic analysis did not reveal a somatic mutation of the OTC gene in this patient. The hyperammonemic encephalopathy was reversed by the infusion of arginine, a common treatment for hereditary OTC deficiency. This case may represent a distinct syndrome of reversible hyperammonemia in patients with hepatocellular carcinoma.
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PMID:Postchemotherapy hyperammonemic encephalopathy emulating ornithine transcarbamoylase (OTC) deficiency. 1841 62

Minimal hepatic encephalopathy represents a part of the spectrum of hepatic encephalopathy and is the mildest form. While patients with hepatic encephalopathy have impaired intellectual functioning, personality changes, altered levels of consciousness, and neuromuscular dysfunction, patients with minimal hepatic encephalopathy have no recognisable clinical symptoms of hepatic encephalopathy but have mild cognitive and psychomotor deficits. The prevalence of minimal hepatic encephalopathy has been reported to vary between 30% and 84% in patients with liver cirrhosis and is higher in patients with poor liver function. The diagnosis is usually made by neuropsychological and/or neurophysiological testing in cirrhotic patients who are otherwise normal on neurological examination. Minimal hepatic encephalopathy is a clinically significant disorder that impairs the health-related quality of life, predicts the development of overt encephalopathy and is probably associated with a poor prognosis. Thus screening all patients with cirrhosis for minimal hepatic encephalopathy using psychometric testing is recommended. Pharmacologic therapy is recommended for patients diagnosed with minimal hepatic encephalopathy. The pathogenesis of minimal hepatic encephalopathy is considered similar to that of overt hepatic encephalopathy and ammonia plays a key role. Thus ammonia lowering agents such as lactulose, L-ornithine and L-aspartate that have good safety profiles are recommended. Future studies will better define the role of probiotics, levocarnitine and sodium benzoate.
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PMID:Minimal hepatic encephalopathy: time to recognise and treat. 1856 60

A 53-year-old male patient was admitted to our hospital with abdominal pain in the right upper quadrant. There was no change in laboratory investigations other than a slight increase in serum levels of alkaline phosphatase (ALP), alanine aminotransferase (ALT), and gamma glutamyl transferase (GGT). Computed tomography (CT) of the abdomen showed multiple hepatic nodular lesions in the liver. Tru-cut biopsy of the lesions was reported as well-differentiated neuroendocrine carcinoma. The patient received sandostatin treatment. After a few days, the patient was hospitalized in the intensive care unit with disturbance of consciousness and clinical features suggestive of encephalopathy. Serum ammonia level was found highly elevated. After the treatment with L-ornithine-L-aspartate, a remarkable improvement in the level of patient's sensorium occurred as well as a reduction in serum ammonia level within a few days. Transarterial chemoembolization (TACE) was performed one week later. The patient's condition began to worsen along with increase in serum ammonia level and he died because of hyperammonemic encephalopathy. There are case reports of hyperammonemia with some malignancies such as multiple myeloma, plasma cell leukemia, and leiomyosarcoma, or in some patients who have received chemotherapy. This case may suggest an association between hyperammonemia and neuroendocrine tumors.
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PMID:Hyperammonemic encephalopathy in a patient with primary hepatic neuroendocrine carcinoma. 1903 Oct 17

Excessive protein intake can cause hepatic encephalopathy (HE). Restricting protein in HE is becoming a controversy, because it can worsen malnutrition. This article reports the case of an under nourishment HE which is treated with L-ornithine-L-aspartate (LOLA) and given appropriate diet according to the nutrition status. A 62-year-old man came with chief complaint of having reduced consciousness since 6 hours before admission. He had been diagnosed as liver cirrhosis for 6 years. Several days prior to admission he took high protein diet. Physical examination revealed under nutrition and unconsciousness. Hepatic encephalopathy was confirmed with low critical flicker test (CFF), and high blood ammonia level. He was treated with adequate diet and LOLA to decrease blood ammonia and improve the CFF. During the treatment, consciousness improved to normal, CFF increased and ammonia level decreased. In this case, the HE was treated with LOLA without protein restriction. The HE improvement, in this circumstance may be caused of LOLA treatment that helps decrease the plasma ammonia level. Adequate diet, 35-40 kcal/kgBW/d and protein intake 1.5 g/kgBW/d, has been administered safely to this patient with stage II hepatic encephalopathy. LOLA seemed to be effectively reduced ammonia level and improved the encephalopathy.
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PMID:Normal protein diet and L-ornithine-L-aspartate for hepatic encephalopathy. 2072 70


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