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

Plasma amino acids were compared in three groups of patients with alcoholic liver disease including stable cirrhosis, acute alcoholic hepatitis without portal-systemic encephalopathy, and cirrhosis with encephalopathy. In addition, plasma amino acids were correlated with nitrogen balance in patients with acute alcoholic hepatitis and with clinical improvement in patients with encephalopathy. Significant differences in plasma amino acids within these groups were present. Plasma amino acids did not change with improvement in portal-systemic encephalopathy, and abnormalities of plasma amino acids did not prevent maintenance or attainment of positive nitrogen balance in patients with acute alcoholic hepatitis.
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PMID:Relationship of plasma amino acids to nitrogen balance and portal-systemic encephalopathy in alcoholic liver disease. 707 4

A disturbance of cerebral neurotransmitters and an accumulation of octopamine, a putative false neurotransmitter, have been found in patients with uremic encephalopathy who manifest disorientation, somnolence, asterixis, and coma--symptoms also seen in portal systemic encephalopathy (PSE). Altered plasma concentrations of the neutral amino acids (NAAs) and increased blood-brain NAA transport may play a role in PSE, and in the present study plasma amino acid concentrations and blood-brain barrier NAA transport were investigated in rats with acute and chronic uremia. Acute uremia was produced by unilateral nephrectomy and occlusion of the renal artery of the remaining kidney for 70 minutes; the animals were studied 24 hours later. Chronic uremia was produced by unilateral nephrectomy and 70% to 80% devascularization of the remaining kidney; these animals were studied 2 weeks later. Brain uptake was studied with the technique of Oldendorf, and blood and brain amino acids (AAs) were measured. The blood urea nitrogen (BUN) level in rats with acute uremia increased to 108 mg/dl, in rats with chronic uremic 54 mg/dl, and in sham-operated rats 22 mg/dl. In both uremic groups there was a decrease in plasma branched-chain AAs. In the brain these AA levels were normal, while levels of phenylalanine, tyrosine, and histidine were increased in uremic rats.
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PMID:Blood-brain barrier derangement in uremic encephalopathy. 708 66

Since in a previous study hypoxia and subsequent hypotension were considered to be essential for the pathogenesis of carbon monoxide encephalopathy (CO-encephalopathy), experiments were conducted to see whether a combination of nitrogen hypoxia and subsequent systemic hypotension of similar degree and duration as in the previous experimental CO poisoning could induce the same lesion in the CNS of cats. The partial pressure of blood oxygen was reduced to less then 26 mm Hg by increasing the concentration of nitrogen in N2/O2 gas to be inhaled in 1.5h and then the aortic blood pressure (BP) was reduced to 60-80 mm Hg by blood depletion and ganglion-blockage for 1h. In 11 of the 15 cats, lesions were produced in the CNS which were similar by light and electron microscopy to those in CO-encephalopathy. In control groups which were treated by hypoxemia only, hypotension only or a combination CO2-gas inhalation and hypotension without hypoxemia, such lesions were not found in the cerebral white matter. Considering the pathogenesis of lesions in the cerebral white matter in both nitrogen hypoxia and CO-poisoning, two factors i.e., hypoxemia and subsequent systemic hypotension, are common and essential. Further, the enormous vasodilatation in the cerebral white matter induced by hypoxemia and subsequent drop in BP seem to cause a more severe circulatory disturbance in the cerebral white matter than in the cortex.
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PMID:Comparative study on pathogenesis of selective cerebral lesions in carbon monoxide poisoning and nitrogen hypoxia in cats. 709 Jul 35

A reexamination was conducted on 90 of 231 patients who had undergone portal-systemic shunt operations 2-15 years ago in our hospital due to massive esophageal varix bleeding. The results show that decompressing procedures represent the only therapeutic principle successfully preventing recurrence of massive esophageal hemorrhage over an extended period of time. Postoperative encephalopathy occurred relatively infrequently. This finding imposes considerably restraint on the use of this term as a weighty argument against portocaval shunts, especially because nitrogen substances are often known to pass unchanged from the intestinal tract to the vena cava and thus ultimately to the brain in patients with liver cirrhosis not undergoing surgery. The possibility of preventing recurrence of massive esophageal hemorrhage by protal decompression is meant to relieve the patient's constant fear of an incident putting his liver in jeopardy.
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PMID:[Massive hemorrhage of the esophageal varix: standardized treatment and long-term results after portosystemic anastomosis (author's transl)]. 720 76

The use in cirrhosis of so-called selective amino acid solutions, i.e. solutions rich in branched and poor in aromatic acids, is readily explained by the proven alteration of the basal amino acid picture in this disease. It is also known that marked haemorrhage, stress, surgery and massive dehydration exacerbate the position and open the way to encephalopathy. A study was therefore made of the clinical, biochemical, and body fluid picture of cirrhosis patients subjected to portal surgery, and treated pre-, intra- and post-operatively with these special solutions. The treatment proved effective. It is felt that a study could usefully be made of more patients, with account being taken of features indicative of the behaviour of the nitrogen balance.
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PMID:[The use of selective amino acid solutions in the pre- and post-operative treatment of cirrhotics. Preliminary observations]. 737 83

Controversy exists concerning the proper therapy for bleeding gastroesophageal varices secondary to noncirrhotic portal vein thrombosis. Disparity of opinion exists regarding the significance of hepatic portal blood flow and the consequences of total portal-systemic shunts in this condition. One patient is presented who developed severe, crippling encephalopathy 20 years after a central splenorenal shunt. This was associated with loss of portal flow to the liver and marked nitrogen intolerance. Closure of the shunt resulted in restoration of hepatic portal flow via collateral veins (HPI 0.36), clearance of encephalopathy and return to near normal protein tolerance. An additional patient was studied with hyperammonemia and early suggestive signs of encephalopathy eight years following a mesocaval shunt. Four patients were evaluated before and after selective distal splenorenal shunts. All had "cavernous transformation" of the portal vein with angiographic evidence of portal flow to the liver. Postoperative angiograms revealed continued hepatic portal perfusion and a patent shunt in each patient. Radionuclide imaging postoperatively gave an estimated portal fraction of total hepatic blood flow (HPI) of .39 and .60 in two of the four patients. We conclude that 1) there is significant hepatic portal perfusion in noncirrhotic portal vein thrombosis (cavernous transformation), 2) loss of this hepatic portal flow following total shunts can lead to severe encephalopathy, 3) the selective distal splenorenal shunt maintains hepatic portal perfusion and is the procedure of choice when there is a patent splenic vein and surgical intervention is indicated.
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PMID:Noncirrhotic portal vein thrombosis. Physiology before and after shunts. 741 30

Ornithine transcarbamylase deficiency is an X-linked recessive disorder of urea biosynthesis characterized by recurrent, often fatal, hyperammonemic encephalopathy in affected males; carrier females are usually asymptomatic. We report here the clinical and laboratory findings in five symptomatic heterozygous females with ornithine transcarbamylase deficiency. In each case, the onset of symptoms occurred in the 1st year of life, but diagnosis was delayed by up to 15 years. Symptoms included recurrent vomiting with lethargy (five patients), dietary protein intolerance (five), irritability (four), severe acute encephalopathy (three), ataxia (three), and acute hemiparesis (two). All eventually showed evidence of developmental delay or learning difficulties. Two of the three who experienced severe, acute, hyperammonemic encephalopathy suffered serious, permanent neurologic sequelae. Three of the patients showed decreased ornithine transcarbamylase activity in liver obtained by needle biopsy, and the other two had marked orotic aciduria associated with hyperammonemia. Neuroimaging studies demonstrated persistent abnormal lobar attenuation and abnormal signal on computed tomographic scan and magnetic resonance imaging. All patients showed marked symptomatic improvement on treatment with dietary protein restriction supplemented by pharmacologic measures to increase nonprotein nitrogen excretion. Ornithine transcarbamylase deficiency should be considered in the differential diagnosis of acute or chronic encephalopathy in females at any age.
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PMID:Ornithine transcarbamylase deficiency in females: an often overlooked cause of treatable encephalopathy. 749 56

Hyperammonemic encephalopathy has occasionally been reported in uremic patients receiving hyperalimentation with essential amino acid (EAA) as a source of nitrogen as one of the remaining treatment options when the enteric routes were prohibited. We encountered this complication in a patient with normal renal function. A rat animal model was designed to elucidate the mechanism of hyperammonemia resulting from hyperalimentation with EAA as a source of nitrogen. Sixty-four male Long-Evan rats were divided into eight groups receiving feeds ad libitum or different formula of hyperalimentation. Hyperammonemia was found in every rat given hyperalimentation with EAA as the only nitrogen source. Using the Tukey honestly significant difference test, the results were significantly higher (p < 0.001) than that of the control group which were given feeds ad libitum and those groups given hyperalimentation for the same number of days but with mixed amino acid (MAA) as the nitrogen source. Adding arginine to EAA for a further four days after initial administration of EAA hyperalimentation for three days only slightly lowered the mean serum ammonia level. When compared to that of the three-day EAA hyperalimentation group, the difference was not statistically significant. Adding arginine, citrulline, and ornithine to EAA for a further four days significantly lowered the mean serum ammonia level. When we changed EAA hyperalimentation to MAA hyperalimentation for a further four days, the mean serum ammonia level decreased dramatically to nearly normal. Hyperalimentation using EAA as the exclusive source of nitrogen resulted in hyperammonemia. A deficiency of arginine or other amino acids of the urea cycle failed to account completely for the hyperammonemia observed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hyperammonemic encephalopathy due to essential amino acid hyperalimentation. 785 37

Ifosfamide, a nitrogen mustard derived alkylating agent commonly used in the treatment of solid tumors, has been associated with neurotoxicity in 5-33% of treated patients. Encephalopathy most often occurs during or shortly following drug administration, with increased drowsiness or irritability, confusion, hallucinations, visual blurring, extrapyramidal dysfunction, cranial nerve abnormalities, incontinence, generalized muscle twitching, seizures, and coma reported in infants, children, and older adults. While most reported neurologic abnormalities associated with ifosfamide have been reversible, encephalopathy resulting in death has occurred. We now report an infant who developed ifosfamide-induced encephalopathy, loss of developmental milestones, progressive brain atrophy, and cessation of cranial growth. This is the first case of cerebral atrophy and loss of developmental milestones that has been reported in a pediatric patient treated with ifosfamide. Given the efficacy of this anti-neoplastic agent and its increasing use in pediatrics, further investigation is indicated, especially in infants where brain growth is ongoing.
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PMID:Cerebral atrophy in an infant following treatment with ifosfamide. 805 12

In a randomized cross-over comparison, the effects of a mainly vegetable protein diet were compared with an animal protein diet in eight patients with cirrhosis and chronic permanent encephalopathy, under optimum lactulose therapy. After a run-in period, patients were fed two equi-caloric, equi-nitrogenous diets for 7 days (71 g total proteins), containing either 50 g protein of animal origin or 50 g vegetable proteins. In the last 3 days of each period, nitrogen balance was significantly better during the vegetable protein diet (+0.2 (SD 1.4) g vs. -1.7 (2.4); P < 0.01), the difference being entirely due to a reduced urinary nitrogen excretion. Average daytime integrated blood glucose was slightly higher during vegetable proteins, whereas insulin, plasma amino acids and ammonia were lower. The clinical grading of encephalopathy improved slightly on vegetable proteins, and psychometric tests improved significantly, but remained grossly abnormal. Compliance to dietary manipulation was good. The data prove that a mainly vegetable protein diet is worthwhile in cirrhotic patients with chronic encephalopathy under optimum lactulose therapy. Improved nitrogen balance may be related to more effective nitrogen use for protein synthesis, probably due to blunted hormonal response, and largely outweighs the effects on encephalopathy.
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PMID:Vegetable versus animal protein diet in cirrhotic patients with chronic encephalopathy. A randomized cross-over comparison. 848 1


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