Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0036572 (seizures)
 80,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tumor lysis syndrome (TLS) is an important metabolic disorder frequently encountered in the management of a variety of cancers including lymphoma, leukemia, and neuroblastoma. Delayed recognition can result in a variety of biochemical abnormalities resulting in life-threatening complications such as renal failure, arrhythmias, and seizures. Identification of high-risk patients and early recognition of the syndrome is crucial in the early institution of appropriate prophylaxis and treatment. Recent advances in the understanding of urate metabolism, development of new urate-lowering drugs, and the application of biomarkers, calculation methods, and prognostic models to identify high-risk patients will pave the way in improving the management of TLS. We included in this review the new information regarding the urate transporters URAT-1, organic anion transporter 1/3, and MRP4; the urate elimination pathway; a comparison of the old- (allopurinol, native uricase) and new- (febuxostat, Y-700, PEG-uricase, rasburicase) generation urate-lowering agents; and application of new biomarkers (cystatin-C, neutrophil gelatinase-associated lipocalin, kidney injury molecule 1), estimated glomerular filtration rate and calculation methods (modification of diet in renal disease and prognostic model (Penn Predictive Score of Tumor Lysis Syndrome) in the identification of high-risk patients, and alternative unexplored mechanisms (asymmetric dimethylarginine and adenosine) to explain renal injury related to TLS.
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PMID:Tumor lysis syndrome. 1752 97

Tumour lysis syndrome (TLS) is a life-threatening oncological emergency characterized by metabolic abnormalities including hyperuricaemia, hyperphosphataemia, hyperkalaemia and hypocalcaemia. These metabolic complications predispose the cancer patient to clinical toxicities including renal insufficiency, cardiac arrhythmias, seizures, neurological complications and potentially sudden death. With the increased availability of newer therapeutic targeted agents, such as rasburicase (recombinant urate oxidase), there are no published guidelines on the risk classification of TLS for individual patients at risk of developing this syndrome. We convened an international TLS expert consensus panel to develop guidelines for a medical decision tree to assign low, intermediate and high risk to patients with cancer at risk for TLS. Risk factors included biological evidence of laboratory TLS (LTLS), proliferation, bulk and stage of malignant tumour and renal impairment and/or involvement at the time of TLS diagnosis. An international TLS consensus expert panel of paediatric and adult oncologists, experts in TLS pathophysiology and experts in TLS prophylaxis and management, developed a final model of low, intermediate and high risk TLS classification and associated TLS prophylaxis recommendations.
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PMID:Recommendations for the evaluation of risk and prophylaxis of tumour lysis syndrome (TLS) in adults and children with malignant diseases: an expert TLS panel consensus. 2033 65

Tumor lysis syndrome(TLS)is a life-threatening metabolic abnormality caused by the massive and abrupt release of tumor cell components into the blood. TLS can be classified as laboratory TLS(LTLS)or clinical TLS(CTLS). LTLS is characterized by 2 or more of the following metabolic abnormalities: hyperuricemia, hyperkalemia, and hyperphosphatemia. CTLS comprises LTLS in addition to 1 or more of the following symptoms: renal insufficiency, cardiac arrhythmia/sudden death, and seizures. The prevention and treatment of TLS includes rigorous hydration, hyperuricemia management, and frequent monitoring of electrocytes and correction of electrolyte abnormalities. Rasburicase, a recombinant urate oxidase, can rapidly reverse hyperuricemia. With the introduction of rasburicase in clinical practice, a clinical practice guideline has been released and a recommended risk assessment method and prophylaxis have been advocated. This guideline can be applied uniformly to all patients, not only those with hematological malignancies, but also those with solid tumors. However, the medical environment is changing, with the introduction of a large number of molecular targeted drugs in clinical practice. In the rasburicase era, the serum phosphate concentration will become the most important risk factor associated with CTLS. This guideline will have to be re-evaluated in the near future.
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PMID:[Tumor lysis syndrome and clinical guidelines]. 2474 90

Tumor lysis syndrome (TLS) is a potentially life-threatening complication of cancer therapy characterized by two or more of the following laboratory abnormalities: hyperuricemia, hyperkalemia, hypocalcemia, and hyperphosphatemia, with resultant end-organ damage, eg, renal failure, seizures, or cardiac arrhythmias. High-risk patients include those with highly proliferative cancers and/or large tumor burdens, particularly in the setting of highly effective chemotherapy, among other risk factors. Before 2002, antihyperuricemic drug therapy was limited to allopurinol, a xanthine oxidase inhibitor. Rasburicase, a recombinant urate oxidase, was approved by the US Food and Drug Administration for children in 2002 and adults in 2009, ushering in a new era in TLS therapy. We attempted to critically appraise the available evidence supporting the perceived benefits of rasburicase in the management of TLS. A Medline search yielded 98 relevant articles, including 26 retrospective and 22 prospective studies of rasburicase for the treatment of TLS, which were then evaluated to determine the best available evidence for the effectiveness of rasburicase in terms of disease-oriented, patient-oriented, and economic outcomes. Rasburicase is now a standard of care for patients at high risk of TLS despite continuing debate on the correlation between its profound and rapid lowering of plasma uric acid levels with hard patient outcomes, eg, need for renal replacement therapy and mortality. Rasburicase is dramatically effective in lowering plasma uric acid levels. The mortality and cost-effectiveness benefits of this expensive drug remain to be conclusively proven, and well designed, randomized controlled trials are needed to answer these fundamentally important questions.
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PMID:Rasburicase in the management of tumor lysis: an evidence-based review of its place in therapy. 2561 Mar 45

Tumor lysis syndrome (TLS) occurs in malignancies with high proliferative potential and tumor burden, such as lymphomas and leukemias. TLS syndrome is an oncologic emergency, requiring prompt intervention. The metabolic derangements cause acute kidney failure and may lead to cardiac arrhythmias, seizures, and death. With the advent of rasburicase, a recombinant urate oxidase, there has been a decline in the TLS-mediated renal failure and the need for dialysis. The recommended regimen and doses pose a heavy financial burden for patients in developing countries like India. With data and studies proving a similar efficacy for the reduced dose and lesser number of rasburicase, we report here a case series of seven children with acute leukemias, whose TLS was managed by a single dose of rasburicase. A retrospective analysis of case records of seven children with acute lymphoblastic leukemia and TLS, admitted to our Pediatric Oncology Unit of our Hospital between the period 2011 and 2013, was done. All our patients responded to a single dose, indicating that in appropriately monitored patients, single dose followed by as-needed dosing can be cost-saving.
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PMID:Single dose rasburicase in the management of tumor lysis syndrome in childhood acute lymphoblastic leukemia: A case series. 2583 46

Recent evidence points at an important role of endogenous cell-damage induced pro-inflammatory molecules in the generation of epileptic seizures. Uric acid, under the form of monosodium urate crystals, has shown to have pro-inflammatory properties in the body, but less is known about its role in seizure generation. This study aimed to unravel the contribution of uric acid to seizure generation in a mouse model for acute limbic seizures. We measured extracellular levels of uric acid in the brain and modulated them using complementary pharmacological and genetic tools. Local extracellular uric acid levels increased three to four times during acute limbic seizures and peaked between 50 and 100 min after kainic acid infusion. Manipulating uric acid levels through administration of allopurinol or knock-out of urate oxidase significantly altered the number of generalized seizures, decreasing and increasing them by a twofold respectively. Taken together, our results consistently show that uric acid is released during limbic seizures and suggest that uric acid facilitates seizure generalization.
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PMID:Uric acid is released in the brain during seizure activity and increases severity of seizures in a mouse model for acute limbic seizures. 2677 5

There is a continuous drive to find new, improved therapies that have a different mechanism of action in order to help diminish the sizable percentage of persons with pharmacoresistant epilepsy. Uric acid is increasingly recognized as contributing to the pathophysiology of multiple disorders, and there are indications that uric acid might play a role in epileptic mechanisms. Nevertheless, studies that directly investigate its involvement are lacking. In this study we assessed the susceptibility to pentylenetetrazole- and pilocarpine-induced seizures in mice with genetically altered uric acid levels by targeting urate oxidase, which is the enzyme responsible for uric acid breakdown. We found that although disruption of urate oxidase resulted in a decreased susceptibility to all behavioral end points in both seizure models, overexpression did not result in any alterations when compared to their wild-type littermates. Our results suggest that a chronic increase in uric acid levels may result in decreased brain excitability.
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PMID:Disruption, but not overexpression of urate oxidase alters susceptibility to pentylenetetrazole- and pilocarpine-induced seizures in mice. 2715 16