Clinical Neuroscience

[Role of zonisamid in treating epilepsy, Parkinson disorders and other neurological diseases]


NOVEMBER 30, 2009

Clinical Neuroscience - 2009;62(11-12)

[On the basis of six randomized controlled trials, zonisamide (ZNS) can be prescribed as add-on treatment in focal adulthood epilepsy in USA and Europe. In Japan, it can be prescribed as first-line monotherapy drug - independent of age. ZNS may also be effective in idiopathic generalized epilepsy and some difficult-to-treat epilepsies including West, Lennox-Gastaut, or Dravet syndromes. The most frequent side effects of ZNS are related to central nervous system occurring in 19%. Kidney stones and oligohidrosis are ZNS-specific side effects. Loss of appetite and weight are usually “beneficial” effects. ZNS is not recommended in pregnancy. ZNS can be taken once daily, which may be beneficial in non-compliance. The pathomechanism of ZNS is different from other antiepileptic drugs. ZNS has an effect on the voltage-gated Na+- and T-type Ca2+ channels as well as on the dopaminerg, glutamaterg, cholinerg, and GABAerg systems. The multiple way of action may be the reason why ZNS seems to be a broad-spectrum drug and beneficial in various neurological disorders. ZNS reduces production of free radicals according to in vitro and in vivo studies. Animal experiments suggest that ZNS may be a neuroprotective agent. Based on an adequate randomized controlled trial, ZNS is effective in adjuctive treatment of Parkinson disorder. A peculiar benefit of the ZNS is that parallel to its positive effect on motor impairment it also reduces severity of dyskinesias. ZNS may be effective in bipolar disorder, obesity, eating disorders, and migraine prophylaxis.]



Further articles in this publication

Clinical Neuroscience



Clinical Neuroscience

[New vistas and views in the concept of generalized epilepsies]


[The aim of this work is to show explicitly why the “idiopathic generalized epilepsy” concept becomes outfashioned and untenable. As the concept of “generalized epilepsies” is from long ago closely related to the thalamo-cortical system, we briefly summarize the functional anatomy, the double working mode of the thalamo-cortical system in different vigilance states and it’s role in development of the spike - wave pattern. The next part shows weaknesses of this concept from the EEG, seizure semiology, and neuroimaging point of view. Further experimental and clinical arguments are accumulated from the reflex epileptic features in IGE, indicating local/regional cortical hyperexcitability. A separate part is devoted to genetic aspects of the question. Lastly implications to epilepsy classification are shown and an outlook toward a unified epilepsy concept is provided. The epileptic disorder of the thalamo-cortical system is responsible for the development of “generalized", synchronous spike-wave paroxysms as the common neurophysiological background in “primary” - idiopathic and in “secondary” generalized epilepsies. This disorder is specifically related to the burstfiring working mode of the thalamo-cortical system during NREM sleep (is an epileptic exageration of it). The “generalized” epilepsy category should be abandoned, being misleading. Epilepsies are proposed to be classified according to their network properties and relations to different physiological systems of the brain. The different phenotypes, named earlier idiopathic (primary) generalized, or symptomatic (secondary) generalized (with encephalopathic features), should be delineated depending on the following factors: 1. speed and extent of syncronization within the thalamo-cortical system, 2. the way how the thalamo-cortical system is involved, 3. which kind of cortical triggers play role, 4. the degree and level of the disorder (restricted to the molecular level or extended to the level of structural alterations - in the cortex or more diffusely, 5. genetic targets and features.]

Clinical Neuroscience

[Quantitative analysis of the genes determining spinal muscular atrophy]


[Spinal muscular atrophy (SMA) is one of the most common autosomal recessive diseases, affecting approximately one in 10.000 live births and with a carrier frequency of approximately one in 35. The disease is caused by a deficiency of the ubiquitous protein survival of motor neuron (SMN), which is encoded by the SMN1 and SMN2 genes. Due to a single nucleotide polymorphism in exon 7, SMN2 produces less full-length transcript than SMN1 and cannot prevent neuronal cell death at physiologic gene dosages. On the other hand, the copy number of SMN2 affects the amount of SMN protein produced and the severity of the SMA phenotype. SMN gene dosage analysis can determine the copy number of SMN1 to detect carriers and patients heterozygous for the absence of SMN1 exon 7. This study provides copy number estimation of SMN1 gene by real-time PCR technique in 56 SMA type I., II., III. patients, 159 parents and healthy relatives and in 152 undefined SMA patients. Among the family members, 91 carriers have been detected and in 56 patients homozygous deletion of SMN1 exon 7 has been confirmed. Moreover, in 12 patients compound heterozygosity of SMN1 exon 7 mutation has been detected, thus providing the possible diagnosis of SMA. In 94 patients, copy number of SMN2 has also been evaluated and a good correlation has been found with the phenotype of the disease. Due to the genetic complexity and the high carrier frequency, accurate risk assessment and genetic counselling are particularly important for the families. These new results provide improvement of the diagnostic service in SMA in Hungary with focus on proper genetic counselling and possible enrolment of the patients in future therapeutic interventions.]

Clinical Neuroscience

[Guillain–Barré syndrome in childhood]

KOLLÁR Katalin, LIPTAI Zoltán, ROSDY Beáta, MÓSER Judit

[Background - Guillain-Barré syndrome (GBS) is clinically well known since 1916. It can occur at any age. Its main characteristic is acute rapidly ascending flaccid paresis. It is a neuro-immunologic disorder with heterogeneous background. In Hungary we could not find reports about big paediatric population with GBS. Patient and method - We analysed retrospectively the data of 38 children diagnosed and treated with GBS at the Neurological Department of Paul Heim Children’s Hospital or at the Paediatric Department of St. László Hospital from January 2000 till April 2008. We analysed the clinical characteristics, seriousness of clinical signs, laboratory results, and electrophysiological features of them as well documented the preceding illness. We observed the effectiveness of our treatment; we measured the speed and time of the healing process and documented the residual clinical signs. Results - 35 children could be classified as having acute inflammatory demyelinating polyneuropathy (AIDP), 2 as having acute motor axonal neuropathy (AMAN) and 1 as Miller-Fisher syndrome. By those patients who at the very beginning did not show the characteristic clinical signs, electrophysiology helped in establishing the diagnosis. By one child spinal MRI with gadolinium supported our diagnosis. Those children, who lost their ambulation, got immunotherapy: intravenous immunoglobulin (IVIG) or plasmapheresis (PEX). Both method seemed to be effective. None of our patients died. All were cured. By five patients residual clinical symptoms could be found. Conclusion - The disease process, the relative incidence of each subtype of GBS is nearly similar to that in Western Europe and North America according to the literature. By the currently used immune therapy most of the pediatric patients recover fully within a short time.]

Clinical Neuroscience

[Myelination disturbance in a patient with hyperuricemia and hyperserotoninemia combined with 18q deletion syndrome]

LÁSZLÓ Aranka, VÖRÖS Erika, BUGA Klára, HORVÁTH Katalin, MAYER Péter, OSZTOVICS Magda†, PÁVICS László, SVEKUS András, PATTERSON C. Marc

[We previously reported a male patient with an 18q21.3 deletion, hyperuricemia and typical symptoms of the Lesch- Nyhan syndrome who lacked hypoxanthine-guanine-phosphoribosyl- transferase (HGPRT) deficiency. The patient developed progressive peripheral neuropathy in additon to his profound mental retardation and self-injurious behavior. At the age of 23 years MR imaging revealed globally delayed myelination with relative sparing of the corpus callosum and frontal lobes. They were focal hyperintensities suggestive of gliosis. Multimodality evoked potentials found evidence of impaired central and peripheral conduction. Single photon emission computed tomographic (SPECT) imaging demonstrated left frontal hyperperfusion and under it a temporoparietal hypoperfusion.]

All articles in the issue

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Clinical Neuroscience

Effects of valproate, carbamazepine and levetiracetam on Tp-e interval, Tp-e/QT and Tp-e/QTc ratio


Aim - To evaluate P-wave dispersion before and after antiepileptic drug (AED) treatment as well as to investigate the risk of ventricular repolarization using the Tpeak-Tend (Tp-e) interval and Tp-e/QT ratio in patients with epileptic disorder. Methods - A total of 63 patients receiving AED therapy and 35 healthy adults were included. ECG recordings were obtained before and 3 months after anti-epileptic treatment among patients with epilepsy. For both groups, Tp-e and Tp-e/QT ratio were measured using a 12-lead ECG device. Results - Tp-e interval, Tpe/QT and Tp-e/QTc ratios were found to be higher in the patient group than in the control group (p<0.05, for all), while QTmax ratio was significantly lower in the patient group. After 3 months of AED therapy, significant increases in QT max, QTc max, QTcd, Tp-e, Tp-e/QT, and Tp-e/QTc were found among the patients (p<0.05). When the arrhythmic effects of the drugs before and after treatment were compared, especially in the valproic acid group, there were significant increases in Tp-e interval, Tp-e/QT and Tp-e/QTc values after three months of treatment (p<0.05). Carbamazepine and levetiracetam groups were not statistically significant in terms of pre- and post-treatment values. Conclusions - It was concluded that an arrhythmogenic environment may be associated with the disease, and patients who received AED monotherapy may need to be followed up more closely for arrhythmia.

Clinical Neuroscience

[Zonisamide: one of the first-line antiepileptic drugs in focal epilepsy ]


[Chronic administration of antiepileptic drugs without history of unprovoked epileptic seizures are not recommended for epilepsy prophylaxis. Conversely, if the patient suffered the first unprovoked seizure, then the presence of epileptiform discharges on the EEG, focal neurological signs, and the presence of epileptogenic lesion on the MRI are risk factors for a second seizure (such as for the development of epilepsy). Without these risk factors, the chance of a second seizure is about 25-30%, while the presence of these risk factors (for example signs of previous stroke, neurotrauma, or encephalitis on the MRI) can predict >70% seizure recurrence. Thus the International League Against Epilepsy (ILAE) re-defined the term ’epilepsy’ which can be diagnosed even after the first seizure, if the risk of seizure recurrence is high. According to this definition, we can start antiepileptic drug therapy after a single unprovoked seizure. There are four antiepileptic drugs which has the highest evidence (level „A”) as first-line initial monotherapy for treating newly diagnosed epilepsy. These are: carbamazepine, phenytoin, levetiracetam, and zonisamide (ZNS). The present review focuses on the ZNS. Beacuse ZNS can be administrated once a day, it is an optimal drug for maintaining patient’s compliance and for those patients who have a high risk for developing a non-compliance (for example teenagers and young adults). Due to the low interaction potential, ZNS treatment is safe and effective in treating epilepsy of elderly people. ZNS is an ideal drug in epilepsy accompanied by obesity, because ZNS has a weight loss effect, especially in obese patients.]

Clinical Neuroscience

[Decisional collisions between evidence and experience based medicine in care of people with epilepsy]


[Background – Based on the literature and his long-term clinical practice the author stresses the main collisions of evidence and experience based medicine in the care of people with epilepsy. Purpose – To see, what are the professional decisions of high responsibility in the epilepsy-care, in whose the relevant clinical research is still lacking or does not give a satisfactory basis. Methods – Following the structure of the Hungarian Guideline the author points the critical situations and decisions. He explains also the causes of the dilemmas: the lack or uncertainty of evidences or the difficulty of scientific investigation of the situation. Results – There are some priorities of experience based medicine in the following areas: definition of epilepsy, classification of seizures, etiology – including genetic background –, role of precipitating and provoking factors. These are able to influence the complex diagnosis. In the pharmacotherapy the choice of the first drug and the optimal algorithm as well as the tasks during the care are also depends on personal experiences sometimes contradictory to the official recommendations. Same can occur in the choice of the non-pharmacological treatments and rehabilitation. Discussion and conclusion – Personal professional experiences (and interests of patients) must be obligatory accessories of evidence based attitude, but for achieving the optimal results, in some situations they replace the official recommendations. Therefore it is very important that the problematic patients do meet experts having necessary experiences and also professional responsibility to help in these decisions. ]

Clinical Neuroscience

[LADA type diabetes, celiac diasease, cerebellar ataxia and stiff person syndrome. A rare association of autoimmune disorders]

SOÓS Zsuzsanna, SALAMON Mónika, ERDEI Katalin, KASZÁS Nóra, FOLYOVICH András, SZŰCS Anna, BARCS Gábor, ARÁNYI Zsuzsanna, SKALICZKI József, VADASDI Károly, WINKLER Gábor

[Celiac disease - in its typical form - is a chronic immunemediated enteropathy with typical clinical symptoms that develops against gliadin content of cereal grains, and is often associated with other autoimmune diseases. In cases of atypical manifestation classic symptoms may be absent or mild, and extra-intestinal symptoms or associated syndromes dominate clinical picture. The authors present a longitudinal follow-up of such a case. A 63-years old woman was diagnosed with epilepsy at the age of 19, and with progressive limb ataxia at the age of 36, which was initially thought to be caused by cerebellar atrophy, later probably by stiff person syndrome. At the age 59, her diabetes mellitus manifested with type 2 diabetic phenotype, but based on GAD positivity later was reclassified as type 1 diabetes. Only the last check-up discovered the celiac disease, retrospectively explaining the entire disease course and neurological symptoms. By presenting this case, the authors would like to draw attention to the fact that one should think of the possibility of celiac disease when cerebellar ataxia, progressive neurological symptoms and diabetes are present at the same time. An early diagnosis may help to delay the progression of disease and help better treatment.]

Clinical Neuroscience

Relationship between Status Epilepticus Severity Score and etiology in adult NCSE patients

GENC Fatma, ERDAL Abidin, AKCA Gizem, KARACAY Ertan, GÖKSU Özaydın Eylem, KUTLU Gülnihal, GÖMCELI Bicer Yasemin

Purpose - Nonconvulsive status epilepticus (NCSE) is a heterogeneous, severe neurological disorder of different etiologies. In this study, the outcomes of NCSE episodes was assessed in a large series of adult patients. Our objective was to evaluate relationship between Status Epilepticus Severity Score (STESS) and etiology and the role of etiological factors on predicting the outcomes. Method - In this retrospective study, the medical records of 95 patients over 18 years of age who were diagnosed with NCSE between June 2011 and December 2015 were reviewed. Their treatment and follow-up for NCSE was performed at the Epilepsy Unit in Department of Neurology, Antalya Research and Training Hospital. Etiological factors thought to be responsible for NCSE episodes as well as the prognostic data were retrieved. The etiological factors were classified into three groups as those with a known history of epilepsy (Group 1), primary neurological disorder (Group 2), or systemic/unknown etiology (Group 3). STESS was retrospectively applied to patients. Results - There were 95 participants, 59 of whom were female. Group 1, Group 2, and Group 3 consisted of 11 (7 female), 54 (33 female), and 30 (19 female) patients, respectively. Of the 18 total deaths, 12 occurred in Group 2, and 6 in Group 3. The negative predictive value for a STESS score of ≤ 2 was 93.88% (+LR 2.05 95% CI: 1.44-2.9 and -LR 0.3 95% CI 0.10-0.84 ) in the overall study group. While the corresponding values for Group 1 (patients with epilepsy), Group 2 (patients with primary neurological disorder), and group 3 (patients with systemic or unknown etiology) were 100%, 92.59% (+LR 2.06 95%CI: 1.32-3.21 and -LR 0.28 95% CI 0.08-1.02 ) 83.33% (+LR 1.14 95%CI: 0.59-2.9 and -LR 0.80 95% CI 0.23-2.73). Conclusions - This study included the one of the largest patients series ever reported in whom STESS, a clinical scoring system proposed for use in patients with status epilepticus, has been implemented. Although STESS appeared to be quite useful for predicting a favorable outcome in NCSE patients with epilepsy and primary neurological disorders, its predictive value in patients with systemic or unknown etiology was lower. Further prospective studies including larger NCSE samples are warranted.