Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023380 (lethargy)
 5,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Late onset of symptoms in a 12 1/2-year-old male with ornithine transcarbamylase (OTC) deficiency were associated with unusual histological features in the liver. The patient presented with an acute onset of hyperammonemia and altered mental status after a 2-day prodrome of vomiting and lethargy. Physical examination showed a combative and disoriented male with icteric sclerae but with no fever or hepatomegaly. The plasma ammonia level was 282 microM. Enzyme assays of liver tissue obtained by percutaneous needle biopsy showed OTC activity of approximately 3% of normal; carbamyl phosphate synthetase was normal. Histopathological findings included severe microvesicular centrilobular steatosis. Hepatic architecture and reticulin framework were well preserved. Many hepatocyte nuclei were filled with glycogen. Electron microscopy showed mitochondria that were rounded and expanded with cristae at the edge of the mitochondrial membrane. In contrast to other reports, only slight variations in size and shape were seen. Megamitochondria and intramatrical paracrystalline inclusions were not identified. The cytoplasm contained scattered fat globules, peroxisomes, and dilated smooth endoplasmic reticulum. The prominent mitochondrial abnormalities commonly found in OTC deficiency were notably absent.
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PMID:Histopathological findings in a male with late-onset ornithine transcarbamylase deficiency. 800 87

The influence of atmospheric ammonia on the somatic growth, the plasma cortisol and ammonia concentrations, and cell blood counts was investigated in pigs exposed to four concentrations (0, 25, 50, and 100 ppm) for 6 days in a specifically designed air-pollutants exposure chamber. The effects of this gas on pulmonary vascular hemodynamics and permeability and on the endotoxin-induced vascular response were also assessed using an isolated perfused lung preparation. The total pulmonary blood flow resistance (Rt) was partitioned into four components: arterial (Ra), pre-(Ra') and post-(Rv') capillary and venous (Rv). The capillary filtration coefficient (Kf,c) was evaluated by using a gravimetric technique. None of the concentrations of ammonia significantly modified the plasma cortisol and ammonia concentrations or the differential leukocyte percentages and total white blood cell count, suggesting an absence of stress related to ammonia. In exposed animals, lethargy and a concentration-related depression of the somatic growth were observed. The equation of the regression line plotted relating the mean values of the changes in body weight gain recorded over the exposure period expressed as percentages of the initial body weight (y) and ammonia concentrations (x) was: y = 3.204 - 0.177x + 0.001x2 (r = 0.99; p < or = 0.013). Endotoxin infused in the perfusion liquid of lungs from unexposed animals for 180 min induced a significant 208% increase in Rt (p < 0.001) which can be ascribed to a 338 and 180% increase in Ra' and Rv', respectively. Endotoxin infusion also induced a 62% (p < or = 0.001) increase in the Kf,c. Exposure of pigs to ammonia at any concentration did not modify the baseline values of any hemodynamic or permeability parameters. However, the hemodynamic response to endotoxins in lungs from pigs exposed to 100 ppm was significantly altered. The increase in Rt, Ra', and Rv' observed in unexposed pigs was completely abolished as shown by the limited changes in Rt (+34.9%). An intermediate reaction (+131.7%) was obtained in pigs exposed to 50 ppm. This inhibiting effect of ammonia was closely correlated with gas concentration by a linear regression (r = 0.99; p < or = 0.037). The changes in the Kf,c recorded in the control group were not modified by exposure to ammonia. It was concluded that exposure of pigs to aerial ammonia concentrations from 0 to 100 ppm for 6 days has no direct effect on the pulmonary microvascular hemodynamics and permeability and induces no stress response.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Effects of atmospheric ammonia on pulmonary hemodynamics and vascular permeability in pigs: interaction with endotoxins. 812 91

Hyperammonemia has been described as a complication of valproic acid therapy but may often be overlooked as a cause of lethargy in the postictal patient who presents to the emergency department. We present the case of a postictal patient with lethargy, hyperammonemia, otherwise normal liver function tests, and a therapeutic valproic acid level. Based on our experience and on previously published data, serum ammonia levels appear to be indicated in all ED patients on valproic acid therapy who present with altered mental status. To the best of our knowledge, this has not been reported previously in the emergency medicine literature.
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PMID:Hyperammonemia secondary to valproic acid as a cause of lethargy in a postictal patient. 816 Oct 72

A 52-year-old patient presented with paroxystic episodes of generalized apraxia, anomia, agraphia and acalculia. The transient character of these attacks was supported by several neuropsychological examinations. Initially a tentative diagnosis of multiple TIA's was made. Treatment consisted of antiplatelet aggregation therapy. Three years later, however, paroxystic neuropsychological symptomatology occurred more frequently with an increase of severity. The patient was again seen and the differential diagnosis included epilepsy or a metabolic disturbance, in casu hepatic encephalopathy. A therapeutic trial with carbamazepine was started but the patient deteriorated further. He developed a flapping tremor and became stuporous. The blood ammonia was high and there were triphasic waves on the EEG. A probable diagnosis of hepatic encephalopathy was made and carbamazepine therapy was withdrawn. There was a good response on low protein diet and lactulose.
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PMID:Paroxystic neuropsychological symptoms as the early expression of hepatic encephalopathy. A case report. 824 70

A 17-year-old girl with Rett syndrome, who was taking no other medications, was treated with L-carnitine (50 mg/kg/day). Within 2 months of initiation of treatment, she became much more alert, developed good eye contact, started reaching for objects with both hands, and answered simple questions with one or two words. L-carnitine was discontinued and within 1 week she lapsed into her pretreatment condition of lethargy with no interest in her environment, not reaching for objects, poor eye contact, and not speaking. One week after L-carnitine was resumed, she again became alert, started reaching for objects, and saying one or two words. Her serum carnitine levels (free and total) were within normal limits before and after L-carnitine treatment, but were higher while she was taking L-carnitine. Her serum ammonia was within normal limits prior to starting L-carnitine. L-carnitine appears to be an effective treatment for this girl with advanced Rett syndrome.
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PMID:L-carnitine as a treatment for Rett syndrome. 827 24

A 24-year-old patient had symptoms of lethargy, convulsions and hyperammonaemia during valproic acid therapy. Cessation of valproic acid treatment brought about an improvement both of the symptoms and of the hyperammonaemia. However, enzymatic analysis after the cessation of valproic acid therapy revealed a complete absence of carbamoylphosphate synthetase (CPS) activity in liver biopsy. A unique polypeptide band, corresponding to the control CPS protein in molecular weight ('CPS-like' protein), was found in normal amounts in the patient's liver on sodium dodecyl sulphate-polyacrylamide gel electrophoresis. This CPS-like protein seemed to be more labile than the control, because the polypeptide band became faint after freeze-thawing. Intravenous administration of L-alanine resulted in a significant increase of serum urea and a transient increase of blood ammonia concentrations. These results strongly suggest that the patient has a labile CPS protein with no activity in vitro but some activity in vivo. We consider that valproic acid may have disrupted some metabolic adaptation by reducing N-acetylglutamate in the liver, which in combination with CPS deficiency induced severe hyperammonaemia.
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PMID:Carbamoylphosphate synthetase deficiency in an adult: deterioration due to administration of valproic acid. 848 2

The effects of 5-2500 microM concentrations of neutral ammonium salts on the binding of ligands to components of the GABAA receptor complex were investigated. [3H]Flunitrazepam binding to the benzodiazepine receptor was enhanced by ammonium (10-500 microM), but not sodium tartrate with EC50 = 98 microM and Emax = 31%. Further increasing ammonium tartrate concentrations (500-2500 microM) decreased [3H]flunitrazepam binding to control levels. The ammonium tartrate-induced increase in [3H]flunitrazepam binding was manifested as a 50% decrease in Kd. Furthermore, GABA increased the potency of ammonium tartrate in enhancing [3H]flunitrazepam binding by 63%. [3H]Ro 15-1788 and [3H]Ro 15-4513 binding to the benzodiazepine receptor was not significantly enhanced by ammonium tartrate (Emax approximately 13%). Ammonium tartrate also increased, then decreased the binding of 500 nM [3H]muscimol to the GABAA receptor (EC50 = 52 microM, Emax = 30%) in a concentration-dependent manner, but had no effect on [3H]SR 95-531 binding (Emax < 16%). The ammonium tartrate-induced alterations in [3H]muscimol binding were demonstrated in saturation assays as the loss of the high affinity binding site and a 27% increase in the Bmax of the low affinity binding site. These results indicate that ammonia biphasically enhances, then returns ligand binding to both the GABA and benzodiazepine receptor components of the GABAA receptor complex to control levels in a barbiturate-like fashion. This suggests that ammonia may enhance GABAergic neurotransmission at concentrations commonly encountered in hepatic failure, an event preceding the suppression of inhibitory neuronal function observed at higher (> 1 mM) ammonia concentrations. This increase in GABAergic neurotransmission is consistent with the clinical picture of lethargy, ataxia and cognitive deficits associated with liver failure and congenital hyperammonemia.
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PMID:Modulation of ligand binding to components of the GABAA receptor complex by ammonia: implications for the pathogenesis of hyperammonemic syndromes. 878 94

Idiopathic hyperammonemia (IHA) has been described as a rare complication of intensive chemotherapy, but there is little data regarding its occurrence after bone marrow transplantation (BMT). IHA is defined as elevated plasma ammonia concentrations (> 200 mumol/l) in the absence of significant liver function abnormality. From a 21 year BMT database of 2358 patients, we have identified 12 patients (0.5%) with IHA, ages 19 to 46 years. Diagnoses included ALL (n = 2), AML (n = 4), CLL (n = 1), CML (n = 3) and aplastic anemia (n = 2). Eight received marrow from a matched sibling donor, three from an unrelated donor and one autologous marrow. IHA occurred between 14 and 106 days after transplant (median, 25 days). Most frequently patients presented with symptoms of a metabolic encephalopathy, with lethargy and confusion evolving into unresponsiveness, metabolic coma and in eight cases, seizures. At diagnosis of IHA, liver functions were normal or only modestly abnormal. Ten of the 12 patients died 1 to 9 days (median 3.5 days) after diagnosis of IHA despite treatment with combinations of dialysis and ammonia-trapping therapy. While IHA is a rare complication of BMT, it is associated with a high mortality. Early recognition of the syndrome by measurement of plasma ammonia concentrations in patients with neurological symptoms may improve outcome.
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PMID:Idiopathic hyperammonemia: a frequently lethal complication of bone marrow transplantation. 880 24

Electromyographic recordings show that, for adult brown trout swum up to their critical swimming speed (Ucrit) in a flume at neutral pH, white muscle recruitment occurred when speeds approached 1 body length s-1 (BL s-1) and continued to Ucrit (approximately 2 BL s-1) at both winter (5 &deg;C) and summer (15 &deg;C) acclimation temperatures. However, in the majority of fish swum up to Ucrit at sublethal acidic pH, continuous white muscle recruitment did not occur, although all swam above 1 BL s-1. Any observed electrical activity of the white muscle in these individuals was, at best, intermittent. Consequently, the mean Ucrit of these fish was approximately half that of fish swum at neutral pH. In all fish at sublethal pH, red muscle activity was observed for the whole duration of the exercise period, showing that swimming speeds greater than 1 BL s-1 were achieved largely aerobically. Fish that were chased around a tank at sublethal pH appeared lethargic in their escape response, exhibiting little or no burst swimming. Other observed effects of exposure to sublethal pH, which may have affected swimming capacity, included increases in the resting levels of blood and muscle ammonia, reduced muscle glycogen stores and reduced muscle ion concentrations.
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PMID:Environmental acidity and white muscle recruitment during swimming in the brown trout (Salmo trutta) 931 56

A 18-year-old Dutch Warmblood mare was referred for colic. Upon arrival, lethargy, blindness, head pressing, ataxia, and circling were the main clinical signs. On rectal examination a hard mass and oedema around the cranial mesenteric artery were palpated. Plasma liver enzyme activities and the ammonia level were elevated. Atrial fibrillation with a pulse frequency of 36-52 beats per minute was noticed. On both sides a holosystolic murmer with the maximum intensity on the right side could be auscultated. Postmortem examination revealed eccentric hypertrophy of the right atrium and a pale spotted myocardium, most prominently of the right ventricle, with secondary venous congestion of the azygos and mesenteric veins. The liver changes were indicative of chronic congestion. Despite the normal pulse rate, it appeared that congestive heart failure due to cardiomyopathy, was responsible for the presenting symptoms of this patient.
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PMID:Atrial fibrillation associated with central nervous symptoms and colic in a horse: a case of equine cardiomyopathy. 956 65


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