Clinical Neuroscience

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

JANSZKY József

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.]

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Clinical Neuroscience

[THE MESSAGE OF THE CHIEF EDITOR]

RAJNA Péter

Clinical Neuroscience

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

HALÁSZ Péter, KELEMEN Anna

[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]

NAGYMIHÁLY Mariann, HERCZEGFALVI Ágnes, TÍMÁR László, KARCAGI Veronika

[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.]

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Clinical Neuroscience

Management of bone metabolism in epilepsy

UÇAN TOKUÇ Ezgi Firdevs , FATMA Genç, ABIDIN Erdal, YASEMIN Biçer Gömceli

Many systemic problems arise due to the side effects of antiepileptic drugs (AEDs) used in epilepsy patients. Among these adverse effects are low bone mineral density and increased fracture risk due to long-term AED use. Although various studies have supported this association with increased risk in recent years, the length of this process has not been precisely defined and there is no clear consensus on bone density scanning, intervals of screening, and the subject of calcium and vitamin D supplementation. In this study, in accordance with the most current recommendations, our applications and data, including the detection of possible bone mineralization disorders, treatment methods, and recommendations to prevent bone mineralization disorders, were evaluated in epilepsy patients who were followed up at our outpatient clinic. It was aimed to draw attention to the significance of management of bone metabolism carried out with appropriate protocols. Epilepsy patients were followed up at the Antalya Training and Research Hospital Department of Neurology, Epilepsy Outpatient Clinic who were at high risk for osteoporosis (use of valproic acid [VPA] and enzyme-inducing drugs, using any AED for over 5 years, and postmenopausal women) and were evaluated using a screening protocol. According to this protocol, a total of 190 patients suspected of osteoporosis risk were retrospectively evaluated. Four patients were excluded from the study due to secondary osteoporosis. Of the 186 patients who were included in the study, 97 (52.2%) were women and 89 (47.8%) were men. Prevalence of low bone mineral density (BMD) was 42%, in which osteoporosis was detected in 11.8% and osteopenia in 30.6% of the patients. Osteoporosis rate was higher at the young age group (18-45) and this difference was statistically significant (p=0.018). There was no significant difference between male and female sexes according to osteoporosis and osteopenia rates. Patients receiving polytherapy had higher osteoporosis rate and lower BMD compared to patients receiving monotherapy. Comparison of separate drug groups according to osteoporosis rate revealed that osteoporosis rate was highest in patient groups using VPA+ carbamazepine (CBZ) (29.4%) and VPA polytherapy (19.4%). Total of osteopenia and osteoporosis, or low BMD, was highest in VPA polytherapy (VPA+ non-enzyme-inducing AED [NEID]) and CBZ polytherapy (CBZ+NEID) groups, with rates of 58.3% and 55.1%, respectively. In addition, there was no significant difference between drug groups according to bone metabolism markers, vitamin D levels, and osteopenia-osteoporosis rates. Assuming bone health will be affected at an early age in epilepsy patients, providing lifestyle and diet recommendations, avoiding polytherapy including VPA and CBZ when possible, and evaluating bone metabolism at regular intervals are actions that should be applied in routine practice.

Clinical Neuroscience

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

YASAR Altun, ERDOGAN Yasar

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

[Personalised epilepsy treatment]

ALTMANN Anna

[Epilepsy is one of the most common chronic neurological disease in childhood. Patients with epilepsy – even with so-called benign epilepsy – need medication for years. During this time, children go through a very big change, not only gaining weight and height, but also changing hormonal and metabolic processes. Maturation processes in different brain areas also take place at different rates depending on age. All of these should be considered when preparing a therapeutic plan. In everyday practice after the diagnosis of epilepsy, the applied drug is most often selected based on the shape and type of seizure. However, a number of other factors need to be considered when designing a therapeutic strategy: 1. efficacy (form of epilepsy, type of seizure), 2. age, gender, 3. pharmacological properties of the drug, 4. adverse drug reaction profile, 5. lifestyle (community), figure (skinny, corpulent, obese), 6. other comorbidities (nutrition, behavioral and learning problems, circulatory disorders, kidney or liver disease), 7. expected interactions with other drugs already used, 8. genetics, 9. other aspects (drug registration and prescription rules). The purpose of this article is to help to decide which antiepileptic drugs are expected to have the least side effects in a particular child with different comorbidities and which medications should be avoided if possible.]

Lege Artis Medicinae

[Epilepsy in coronavirus pandemic]

SZŰCS Anna, HALÁSZ Péter, NARULA Lalit

[We aim to review the impact of COVID-19 pandemic on epilepsy and epilepsy-care. While the virus has no specific link with epilepsy, it may affect the nervous system both directly and indirectly, leading to seizures in several ways. The hyper-coagulable state occurring with the infection may cause strokes leading to seizures. The infection may first manifest in the form of disturbances of consciousness and behaviour, seizures, and even status epilepticus. The interactions of antiviral/antiepileptic drugs need to be taken into account during treatment. The hypercoagulable state induced by COVID-2 infection may cause stroke, which leads to seizures. The infection can occur also as an impaired consciousness of non-epileptic origin. Interactions of antiviral/antiepileptic drugs have also to be taken into account. The pandemic itself as well as quarantines and social distancing may cause anxiety and insomnia, challenge continuous antiepileptic supply; each one carrying the risk of seizing. Young epilepsy patients with learning disabilities and mental health issues are most vulnerable, justifying their hyper-protection. The danger of infection has highlighted the role of telemedicine. Internet-based video communication may ensure full care for chro­nic patients. Those methods favour bes­­ted patients with higher education. Epilepsy does not increase directly the risk of infection, but its comorbidities may worsen the course of the disease. Brain lesions and hypoxia, stress, insomnia and fever joining the infection increase seizure susceptibility. Because the danger of infection ma­de telemedicine an essential tool of pa­tient care, education and better computer supply for those in need is crucial. ]

Clinical Neuroscience

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

RAJNA Péter

[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. ]