Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149958 (complex partial seizures)
 2,563 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seizures are extremely common in the elderly, with an annual incidence reaching 100 per 100000 people aged over 60 years. Most are precipitated by acute symptomatic illnesses such as stroke or systemic disease. Chronic neurological diseases such as Alzheimer's disease may also cause seizures. The aetiology of seizures in many patients is unknown. Seizures may be situational and subside quickly, but the prevalence of chronic seizures--epilepsy--is as high as 1% in the elderly. The majority of seizures are of partial onset, especially complex partial. Complex partial seizures at this age may be very subtle and hard to diagnose. Generalised-onset seizures also occur, perhaps as a result of diffuse changes with aging or degenerative disease or to a combination of genetic and environmental factors. The prognosis for complete seizure control in this population is relatively favourable. Physiological and disease-related changes with aging result in complex pharmacokinetics. Most changes lead to a need for gentler drug treatment with cautious initiation of drugs at lower dosages. Consideration must be given to renal and hepatic function, protein binding and drug interactions. Determinations of free (unbound) drug concentrations are helpful for highly protein bound drugs. The dosages of newer drugs excreted renally must be adjusted based on creatinine clearance. The dosage of most drugs is determined empirically by careful observation of seizure control and adverse effects. Carbamazepine, valproic acid (sodium valproate), gabapentin and lamotrigine have certain theoretical advantages, but comparative trials of anticonvulsants in the elderly are needed. The ideal drug for older patients would be effective, without neurological toxicity, with low protein binding, a nonparticipant in drug interactions and amenable to once daily administration.
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PMID:Epidemiology and drug treatment of epilepsy in elderly people. 1058 73

We report an 8-year-old boy with complex partial seizures due to congenital stroke, treated with valproate for more than 3 years (the last 2 years were on monotherapy) with no complications during that period except for transient thrombocytopenia. His sister had uncomplicated hepatitis A. One month later, the patient became jaundiced, went into fulminant hepatic failure, and quickly became encephalopathic despite discontinuation of valproate, aggressive supportive therapy, and treatment with carmitine. He then died. He had positive hepatitis A IgM; other causes for acute hepatitis were ruled out. Liver pathology revealed distended hepatocytes with cholestasis and microvesicular changes. We could find in the literature two other articles on four cases who developed liver failure with hepatitis A while on valproate. All those cases, however, recovered. In our patient a usually benign disease became deadly, probably because of the concomitant use of a hepatotoxic medication. Immunizing, with hepatitis A vaccine, all children on valproate therapy who are living in, or traveling to, endemic areas should be considered and is probably advisable.
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PMID:Fatality from hepatitis A in a child taking valproate. 1069 1

The delta(2)- 1,2,3- triazoline anticonvulsants (TRs) may be considered as representing a unique class of "built-in" heterocyclic prodrugs where the active "structure element" is an integral part of the ring system and can be identified only by a knowledge of their chemical reactivity and metabolism. Investigations on the metabolism and pharmacology of a lead triazoline, ADD17014 suggest that the triazolines function as "prodrugs" and exert their anticonvulsant activity by impairing excitatory amino acid (EAA) L-Glutamate (L-Glu) neurotransmission via a unique "dual-action" mechanism. While an active primary beta-amino alcohol metabolite from the parent prodrug acts as an N-methyl-D-aspartate (NMDA)/MK -801 receptor antagonist, the parent triazoline impairs the presynaptic release of L-Glu. Various pieces of theoretical reasoning and experimental evidence have led to the clucidation of the dual-action mechanism. Based on the unique chemistry of the triazolines, and their metabolic pathways, biotransformation products of TRs were predicted to be the beta-amino alcohols V and VA, the alpha-amino acid VI, the triazole VII, the aziridine VIII and the ketimine IX. In vivo and in vitro pharmacological studies of the TR and potential metabolites, along with a full quantitative urinary metabolic profiling of TR indicated the primary beta-amino alcohol V as the active species. It was the only compound that inhibited the specific binding of [3H]MK-801 to the MK-801 site, 56% at 10 micro M drug concentration, but itself had no anticonvulsant activity, suggesting TR acted as a prodrug. Three metabolites were identified; V was the most predominant (45.7 +/- 7.6) % of administered drug, with lesser amounts of VA, (17.3 +/- 5.1) % and very minor amounts of aziridine VIII (4.0 +/- 0.02)%. Since only VIII can yield VA, its formation indicated that the biotransformation of TR occurred, at least in part, through aziridine. No amino acid metabolite was detected, which implied that no in vivo oxidation of V or oxidative biotransformation of TR or aziridine by hydroxylation at the methylene group occurred. While triazoline significantly decreased Ca(2+) -dependent, k(+)-evoked L-Glu release (83% at 100 micro M drug concentration ), some triazolines showed an augmentation of 50-63%, in the Cl(-) channel activity, a useful membrane action that reduces the excessive L-Glu release that occurs during epileptic seizures. The high anticonvulsant activity of TRs in a variety of seizure models including their effectiveness in the kindling model of complex partial seizures may be due to their unique dual-action mechanism whereby the TR and V together effectively impair both pre- and postsynaptic aspects of EAA neurotransmission; thus the TRs have clinical potential in the treatment of complex partial epilepsy which is refractory to currently available drugs. Since there is strong evidence that L-Glu plays an important role in human epilepsy as well as in brain ischemia/stroke, and since the TRs act by inhibiting EAA neurotransmission, it was logical to expect that the anticonvulsant TRs may evince beneficial therapeutic potential in cerebral ischemia resulting from stroke as well. And indeed, several TRs, when tested in the standard gerbil model of global ischemia did evince remarkable ability to prevent neuronal death.
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PMID:Rational drug design and the discovery of the delta2-1,2,3-triazolines, a unique class of anticonvulsant and antiischemic agents. 1287 Oct 87

There is a growing number of publications in the recent literature reporting the incidence of non-convulsive status epilepticus in the elderly, including both absence epilepsy and partial epileptic seizures. Absence status epilepticus creates a diagnostic problem because of its clinical features: confusion ranging from slight disorientation to stupor. Duration of such states may vary from one hour to a few weeks, with fluctuations and epileptic features in EEG recording (a typical pattern of spikes-slow waves, 3 Hz frequency, symmetrical and synchronical) that disappear after an intravenous injection of benzodiazepines. Absence status epilepticus can be evoked by toxic, metabolic or pharmacological factors as well as by convulsive epileptic seizures. Besides absence epileptic states of middle-cerebral origin there is a rising concern about absence status resulting from simple or complex partial seizures. Generalized non-convulsive status epilepticus following either simple partial or simple complex seizures is characterized by the presence of various focal signs associated with confusion, stupor or coma. The latter may be masking the clinical picture of an underlying cerebral pathology (e.g. brain tumor, hemorrhage, etc.), and epileptic changes can be seen in EEG recording only. Absence status epilepticus can occur in various forms of brain pathology, including stroke, brain tumors, traumatic lesions and other conditions, as well as in systemic diseases affecting the central nervous system function. Therefore, the authors emphasize the importance of electroencephalography in severely ill and unconscious patients, as well as the role of proper anti-epileptic treatment, as this may improve the outcome.
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PMID:["De novo" non-convulsive status epilepticus in adults and in the elderly]. 1459 57

Acute pathologic neurologic laughter has been described as an ictal phenomenon in epilepsy, as a result of electrical brain stimulation to the cortex and to deep brain structures, in brain tumors, and in stroke. We report what is, to our knowledge, the first report of a case of postictal pathologic laughter. Previously diagnosed with medically refractory complex partial seizures, our patient was admitted to the hospital with phenytoin toxicity. During video-EEG monitoring she experienced multiple brief absence seizures as well as a prolonged episode of absence status epilepticus. Immediately following cessation of the seizure she began to laugh. Her laughter was mirthful and infectious. This lasted several minutes and was followed immediately by several minutes of crying and then a return to normal. We propose that diffuse cortical inhibition led to release of subcortical structures involved in emotional expression. Possible neural substrates of laughter are discussed.
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PMID:Postictal laughter following absence status epilepticus. 1469 18

We investigated the correlation between serum levels of carbamazepine (CBZ) and motor excitability studied by different parameters of transcranial magnetic stimulation (TMS) in patients at the beginning of antiepileptic treatment. A total of 10 patients with complex partial seizures following stroke were treated with loading doses of CBZ. Motor evoked potential (MEP) was recorded from the thenar eminence (TE) muscles of the unaffected arm. In all patients, we studied rest and active motor threshold (rMT, aMT), MEP amplitude and cortical silent period (CSP). In three patients, intracortical inhibition (ICI) and intracortical facilitation (ICF) were measured using paired TMS at short interstimulus intervals (1-25 ms). The recording sessions were performed before treatment and after 7, 15 and 60 days (SD=16 days). Serum level of CBZ were monitored at each recording session. We observed a progressive increase in rMT and aMT until the serum levels of CBZ reached a steady state condition. No significant changes were observed in MEP amplitude, CSP, ICI and ICF. This study documents the increase of both motor threshold and drug serum levels in patients treated with loading doses of CBZ, suggesting a relationship between drug metabolism and the effect on motor cortical excitability.
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PMID:Serum levels of carbamazepine and cortical excitability by magnetic brain stimulation. 1522 26

ASTA Medica is developing retigabine, a carbamic acid ethyl ester and a selective potassium channel opener, for the treatment of complex partial seizures. Phase II trials have commenced [249117], and a multicenter placebo-controlled dosage-finding study has begun in Europe and Australia [392702]. Retigabine is also undergoing phase II testing in Germany, Switzerland, Russia and the US for the potential treatment of epilepsy [323383]. Phase II trials have shown >50% reduction in seizure frequency in 12 of 35 patients with refractory epilepsy [373379]. Phase I clinical trials for epilepsy were successfully completed in Germany in 1995 [180371]. Single and multiple dose trials demonstrated the tolerability and favorable pharmacokinetic behavior of the compound [264306]. The compound showed good compatibility and exhibits an antisense anticonvulsive effect in various preclinical epilepsy models [250565,299344]. Side effects of mild to moderate tiredness, fatigue and nausea were observed [276123]. The spectrum of activity of retigabine resembles that of valproate, but its potency is greater and toxicity is reduced [373379]. The mechanism of action of retigabine is probably multifactorial. Research has shown that retigabine acts as a selective K+ channel opener in neuronal cells and this can be expected to contribute to its anticonvulsant effect [273670]. In addition it demonstrates potentiation of GABA transmission and possibly also weak modulation of sodium and calcium channels [299344]. Retigabine also has neuroprotective activity with potential for the treatment of stroke and neurodegenerative diseases, such as Alzheimer's disease, Huntington's disease and multiple sclerosis [249381]. In February 2000, Lehman Brothers predicted product launch could be as early as 2002 for epilepsy in the US [357788]. In February 1999, Lehman Brothers predicted that the first major launch date of the drug would be 2003, and the year of peak sales to be 2011 [319225].
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PMID:Retigabine (ASTA Medica). 1603 7

Upside-down reversal of vision has rarely been reported in the literature. The reported causes are diverse, including posterior circulation stroke, tumors, trauma, and multiple sclerosis. The term seizure has been used in only two cases in the literature, the cause of which was stroke. To our knowledge, this is the first reported case of cortical dysplasia in the posterior parietal cortex as the cause of complex partial seizures beginning with upside-down reversal of vision. As the pathophysiological characteristics of this phenomenon remain unclear, this case implies that the posterior parietal cortex is a possible anatomical localization of the central integrator of visual extra-personal orientation.
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PMID:Reversal of vision metamorphopsia: a manifestation of focal seizure due to cortical dysplasia. 1624 32

Why is it important to learn about epilepsy in the elderly? The answers are many. As this article has highlighted, compared with younger individuals epilepsy is more common and the causes are more structural and symptomatic than in younger patients (particularly stroke). The clinical presentation is different in the elderly. The diagnosis is more difficult and often delayed. The most common seizures are simple partial and complex partial seizures, which are more often extratemporal in location. Confusion and memory problems are common presenting symptoms and postictal deficits often are prolonged. The prognosis for epilepsy in the elderly generally is favorable for seizure control, but if untreated, depression and quality of life suffer and seizures frequently recur. Seizures respond well at lower serum concentrations of antiepileptic drugs but these patients are also more sensitive (less tolerant) to side effects at lower doses than younger adults.
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PMID:Elders with epilepsy. 1696 51

We encountered an 11-year-old girl with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) who developed occipital lobe epilepsy at the age of 7 years and 4 months. Thereafter she had repeated status epilepticus associated with stroke-like episodes. Status epilepticus consisted of repetitive complex partial seizures with or without secondarily generalized tonic clonic seizures. The seizures did not respond to conventional anticonvulsive drugs, including diazepam, midazolam, phenytoin, lidocaine, chloral hydrate, and thiamylal sodium, and lasted for several hours (mean 9.5 hours). At the age of 11 years, intravenous infusion of L-arginine (0.5 g/kg body weight) was first given five hours after the onset of status epilepticus. The seizures and electroencephalographic abnormalities improved dramatically. After the introduction of L-arginine, in addition to shortened duration of status epilepticus (mean 3 hours), clinical recovery from the status epilepticus was prompt, and the average hospitalization periods could be shortened. There were no obvious adverse effects, including vomiting, hypotension, and urticaria. Our experience suggests that early intravenous administration of L-arginine may be useful in the treatment of status epilepticus associated with stroke-like episode in patients with MELAS.
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PMID:[Usefulness of L-arginine infusion for status epilepticus in mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes]. 1722 17


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