Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In severe Reye's syndrome, with nonspecific intensive supportive therapy, the mortality rate approaches 75%. In many instances, death is due to uncontrolled cerebral edema and elevated intracranial pressure. (ICP). Pentobarbital therapy, sufficient to maintain a blood barbiturate level between 2.5 mg% and 4.0 mg%, was used to control ICP in seven patients with metabolic coma complicated by intracranial hypertension (intracranial pressure greater than 30 mm Hg for 30 min). The nadir of their neurological function was characterized by no response to deep pain, absent or abnormal oculocephalic responses, bilaterally dilated, unreactive pupils, and markedly irregular or absent respirations. Before barbiturate administration hyperventilation, steroids, mannitol, and other supportive therapies commonly used in Reye's syndrome were begun. After institution of pentobarbital therapy, the daily mannitol dose required to maintain the intracranial pressure below 20 mm Hg was significantly reduced (p less than 0.001), from 3.7 +/- 0.3 to 0.5 +/- 0.2 g/kg/day. All the patients survived, and six have no obvious neurological sequelae. Pentobarbital is a useful adjunct for intracranial pressure control in advanced metabolic coma.
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PMID:Pentobarbital therapy for intracranial hypertension in metabolic coma. Reye's syndrome. 63 24

Cerebral biopsies were obtained for electron microscopy 48 and 72 hours after the onset of encephalopathy from a child with severe Reye's syndrome. Gravely ill at the time of craniectomy to relieve cerebral hypertension, the child survived and recovered good brain function; therefore, the biopsy findings appear to reflect the organelle pathology of the brain at a severe yet reversible stage in the disease process. The cardinal ultrastructural changes in the brain in Reye's syndrome are astrocyte swelling and partial deglycogenation, myelin bleb formation and universal injury of neuron mitochondria. The mitochondrial injury consists of matrix disruption with moderate but not massive swelling. Dilatation of rough endoplasmic reticulum and nuclear changes occurred only in neurons with severely altered mitochondria. The organelle pathology of the brain in this case did not resemble the organelle pathology of the brain in human "hepatic encephalopathy" or in experimental ammonia intoxication in primates. The mitochondrial ultrastructure of the cerebral neurons resembled the unique mitochondrial ultrastructural changes seen in the liver parenchyma in Reye's syndrome.
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PMID:Brain ultrastructure in Reye's syndrome. 117 96

A case of cerebral oedema developed during an apparently common attempted suicide with valpromide is reported. The most conspicuous biochemical abnormality was hyperammonaemia. The oedema proved refractory to the standard medical treatment of intracranial hypertension, and decompressive craniectomy was performed with only minor sequelae. The cerebral oedema cum hyperammonaemia syndrome led to the discovery, in this hitherto asymptomatic adult subject, of a 50 per cent deficiency in type a carbamyl phosphate synthetase liver activity. By completing such a deficiency, valproate may produce an extremely serious syndrome resembling the neonatal encephalopathy due to complete enzyme deficiencies in the urea cycle. All valpromide or valproate intoxications probably are cerebral oedemas with hyperammonaemia akin ti Reye's syndrome. All accidents of this type occurring during treatment or poisoning with valproate should be investigated for urea cycle enzyme abnormalities.
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PMID:[Cerebral edema with hyperammonemia in valpromide poisoning. Manifestation in an adult, of a partial deficit in type I carbamylphosphate synthetase]. 297 63

Reye's syndrome (RS) has been defined by the CDC as an acute non-inflammatory encephalopathy and hepatopathy, with no reasonable explanation for the cerebral and hepatic abnormalities. The diagnosis of RS is made by a constellation of clinical and laboratory features, none of which are pathognomonic. The demonstration of a fatty infiltration on liver biopsy is not really specific. On the other hand, the mitochondrial ultrastructural abnormalities appear to be characteristic of RS. Cerebral edema with intracranial hypertension represents the most immediate threat to life, the cause of the encephalopathy being unknown. The treatment of RS consists in perfusion of hypertonic glucose solution and management of intracranial hypertension. Grade I RS should be recognized early and treated with intravenous glucose. A number of metabolic disorders may yield a clinical picture resembling RS. These include disturbances of organic acid metabolism, urea cycle defects, and disorders of carbohydrate metabolism. The pathogenesis of RS is a mitochondrial insult induced by different viruses, drugs, exogenous toxins, and genetic factors. In the USA, pilot studies showed that a majority of RS cases may be attributable to salicylate use. In France, RS remains unfrequent although no precise epidemiological data are available. An epidemiological study appears therefore necessary for a better understanding of this mysterious syndrome. There is a need for a biological marker of the mitochondrial injury.
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PMID:[Reye's syndrome. A current entity which remains enigmatic]. 305 99

Two cases of idiopathic arterial calcification of infancy that occurred in sisters are reported. One patient died at age 14 months after a protracted course characterized by the nephrotic syndrome, blood chemistry abnormalities, hypertension, seizures, and a microangiopathic hemolytic anemia. Her sister died at age 3 weeks after a precipitous illness that initially was misinterpreted at autopsy as Reye's syndrome.
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PMID:Idiopathic arterial calcification of infancy with unusual clinical presentations in sisters. 321 7

We studied intensive care unit (ICU) records of 42 comatose children with acute brain injuries to define the relationship between high arterial blood pressure and poor neurologic recovery. Diagnoses included head trauma, anoxia, Reye's syndrome, and central nervous system infection. The highest systolic blood pressure in all 42 patients exceeded the 95th percentile. In those whose highest systolic pressure exceeded 95th percentile by more than 20 torr, severe neurologic deficit or death occurred in 19 of 34 (56%), while in those with milder hypertension, poor outcome occurred in only one of eight (13%, p = 0.0316). Of those with high blood pressure persisting until ICU discharge, 14 of 19 (74%) had poor outcome, while those with blood pressure normalizing prior to ICU discharge had poor outcome in only six of 23 (26%, p = 0.0026). High blood pressure was not usually a reflex effect of elevated intracranial pressure. This finding suggests that measures to control high blood pressure are indicated in the management of the acutely brain-damaged child.
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PMID:Association of arterial hypertension with poor outcome in children with acute brain injury. 399 62

The association between admission coma score and eventual outcome was assessed using a coma scale developed for children with a variety of central nervous system injuries. As opposed to the Glasgow coma scale, this scale does not demand assessment of verbalization, and thus can be applied to the preverbal or previously intubated child. Cortical function is graded from 6 (purposeful, spontaneous movements) to 0 (flaccid), and brainstem function is graded from 3 (intact) to 0 (absent and apneic). Maximum total score is 9. In 91 children treated for intracranial hypertension, the association was moderately good. The scale was better in predicting the outcome of patients with hypoxic encephalopathy and head trauma than that of patients with Reye's syndrome, meningitis, or encephalitis. No child with a score of less than 3 survived in spite of intensive therapy. Most of these children were flaccid with depressed or absent brainstem reflexes. No child with flaccidity on admission survived.
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PMID:Coma scale for use in brain-injured children. 650 97

Acute intracranial hypertension may respond to intravenous mannitol, but frequent administration can cause cerebral edema or renal problems. We evaluated the use of 20% glycerol administered intravenously as an alternative to mannitol. Intravenous glycerol and mannitol were equally effective in lowering acute elevations of intracranial pressure. The duration of effect was similar for both agents. Side effects of intravenous glycerol were related to concentration, rate, and frequency of administration. In severe encephalopathies, such as Reye syndrome, we recommend infusions of 20% glycerol or 20% mannitol at a dose of 0.5-1.0 gm per kilogram. Glycerol should be administered in 0.45% or 0.9% saline, no faster than 1.5 ml (3.3 mOsm) per minute.
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PMID:Intravenous glycerol and mannitol therapy in children with intracranial hypertension. 680 42

The objective of the present investigation was to determine whether or not tyramine induces coma in experimental animals with impaired mitochondrial monoamine oxidase function, and whether the coma in these animals was a function of increased cerebrospinal fluid (CSF) pressure. Ten mongrel dogs were treated (orally) daily with the monoamine oxidase-inhibiting drug, phenelzine (4.5 mg/kg), over a period of 1 month. The present studies indicated that in phenelzine-treated animals with liver disease and behavioral side effects (n = 4), the i.v. administration of tyramine (1 mg/kg) caused substantial elevation in CSF pressure that exceeded 30 mm Hg (initial pressure 12.5 +/- 2.1). This was followed by substantial accumulation of tyramine, dopamine and norepinephrine concentrations in CSF of these animals. The animals became comatose soon afterward. The administration of tyramine to pretreated (n = 10) or phenelzine-treated animals without liver disease (n = 6) caused only the expected transient increase in blood pressure but with no significant effect on CSF pressure of these animals. These animals recovered fully from the experiment without any ill effect. These studies suggest that tyramine may have obvious implications in the development of intracranial hypertension in Reye's syndrome.
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PMID:Similarity between tyramine-induced neurotoxicity and the coma of Reye's syndrome. 687 68

Although the underlying cause of Reye syndrome is not understood, an effective approach to treatment is based on reversing the known metabolic and pathological abnormalities. A multifaceted therapeutic approach aimed at correcting metabolic derangements and combating intracranial hypertension can result in complete recovery from severe cases of Reye syndrome.
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PMID:Treatment of Reye syndrome. 698 47


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