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Dive into the research topics where Andreas Merkenschlager is active.

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Featured researches published by Andreas Merkenschlager.


Nature Genetics | 2015

De novo loss- or gain-of-function mutations in KCNA2 cause epileptic encephalopathy.

Steffen Syrbe; Ulrike B. S. Hedrich; Erik Riesch; Tania Djémié; Stephan Müller; R. S. Moller; Bridget Maher; Laura Hernandez-Hernandez; Matthis Synofzik; Hande Caglayan; Mutluay Arslan; José M. Serratosa; Michael Nothnagel; Patrick May; Roland Krause; Heidrun Löffler; Katja Detert; Thomas Dorn; Heinrich Vogt; Günter Krämer; Ludger Schöls; Primus-Eugen Mullis; Tarja Linnankivi; Anna-Elina Lehesjoki; Katalin Sterbova; Dana Craiu; Dorota Hoffman-Zacharska; Christian Korff; Yvonne G. Weber; Maja Steinlin

Epileptic encephalopathies are a phenotypically and genetically heterogeneous group of severe epilepsies accompanied by intellectual disability and other neurodevelopmental features. Using next-generation sequencing, we identified four different de novo mutations in KCNA2, encoding the potassium channel KV1.2, in six isolated patients with epileptic encephalopathy (one mutation recurred three times independently). Four individuals presented with febrile and multiple afebrile, often focal seizure types, multifocal epileptiform discharges strongly activated by sleep, mild to moderate intellectual disability, delayed speech development and sometimes ataxia. Functional studies of the two mutations associated with this phenotype showed almost complete loss of function with a dominant-negative effect. Two further individuals presented with a different and more severe epileptic encephalopathy phenotype. They carried mutations inducing a drastic gain-of-function effect leading to permanently open channels. These results establish KCNA2 as a new gene involved in human neurodevelopmental disorders through two different mechanisms, predicting either hyperexcitability or electrical silencing of KV1.2-expressing neurons.


Neurology | 2016

STXBP1 encephalopathy A neurodevelopmental disorder including epilepsy

Hannah Stamberger; Marina Nikanorova; Marjolein Willemsen; Patrizia Accorsi; Marco Angriman; Hartmut Baier; Ira Benkel-Herrenbrueck; Valérie Benoit; Mauro Budetta; Almuth Caliebe; Gaetano Cantalupo; Giuseppe Capovilla; Gianluca Casara; Carolina Courage; Marie Deprez; Anne Destrée; Robertino Dilena; Corrie E. Erasmus; Madeleine Fannemel; Roar Fjær; Lucio Giordano; Katherine L. Helbig; Henrike O. Heyne; Joerg Klepper; Gerhard Kluger; Damien Lederer; Monica Lodi; Oliver Maier; Andreas Merkenschlager; Nina Michelberger

Objective: To give a comprehensive overview of the phenotypic and genetic spectrum of STXBP1 encephalopathy (STXBP1-E) by systematically reviewing newly diagnosed and previously reported patients. Methods: We recruited newly diagnosed patients with STXBP1 mutations through an international network of clinicians and geneticists. Furthermore, we performed a systematic literature search to review the phenotypes of all previously reported patients. Results: We describe the phenotypic features of 147 patients with STXBP1-E including 45 previously unreported patients with 33 novel STXBP1 mutations. All patients have intellectual disability (ID), which is mostly severe to profound (88%). Ninety-five percent of patients have epilepsy. While one-third of patients presented with Ohtahara syndrome (21%) or West syndrome (9.5%), the majority has a nonsyndromic early-onset epilepsy and encephalopathy (53%) with epileptic spasms or tonic seizures as main seizure type. We found no correlation between severity of seizures and severity of ID or between mutation type and seizure characteristics or cognitive outcome. Neurologic comorbidities including autistic features and movement disorders are frequent. We also report 2 previously unreported adult patients with prominent extrapyramidal features. Conclusion: De novo STXBP1 mutations are among the most frequent causes of epilepsy and encephalopathy. Most patients have severe to profound ID with little correlation among seizure onset, seizure severity, and the degree of ID. Accordingly, we hypothesize that seizure severity and ID present 2 independent dimensions of the STXBP1-E phenotype. STXBP1-E may be conceptualized as a complex neurodevelopmental disorder rather than a primary epileptic encephalopathy.


Annals of Neurology | 2016

Benign infantile seizures and paroxysmal dyskinesia caused by an SCN8A mutation

Elena Gardella; Felicitas Becker; Rikke S. Møller; Julian Schubert; Johannes R. Lemke; Line H.G. Larsen; Michael Nothnagel; Holger Thiele; Janine Altmüller; Steffen Syrbe; Andreas Merkenschlager; Thomas Bast; Bernhard J. Steinhoff; Peter Nürnberg; Yuan Mang; Louise Bakke Møller; Pia Gellert; Sarah E. Heron; Leanne M. Dibbens; Sarah Weckhuysen; Hans Atli Dahl; Saskia Biskup; Niels Tommerup; Helle Hjalgrim; Holger Lerche; Sándor Beniczky; Yvonne G. Weber

Benign familial infantile seizures (BFIS), paroxysmal kinesigenic dyskinesia (PKD), and their combination—known as infantile convulsions and paroxysmal choreoathetosis (ICCA)—are related autosomal dominant diseases. PRRT2 (proline‐rich transmembrane protein 2 gene) has been identified as the major gene in all 3 conditions, found to be mutated in 80 to 90% of familial and 30 to 35% of sporadic cases.


Annals of Neurology | 2015

Oligoclonal bands predict multiple sclerosis in children with optic neuritis

Nicole Heussinger; Evangelos Kontopantelis; Janina Gburek-Augustat; Andreas Jenke; Gesa Vollrath; Rudolf Korinthenberg; Peter Hofstetter; Sascha Meyer; Isabel Brecht; Barbara Kornek; Peter Herkenrath; Mareike Schimmel; Kirsten Wenner; Martin Häusler; Soeren Lutz; Michael Karenfort; Astrid Blaschek; M Smitka; Stephanie Karch; Martin Piepkorn; Kevin Rostasy; Thomas Lücke; Peter Weber; Regina Trollmann; Jörg Klepper; Martin Häussler; Regina Hofmann; Robert Weissert; Andreas Merkenschlager; Mathias Buttmann

We retrospectively evaluated predictors of conversion to multiple sclerosis (MS) in 357 children with isolated optic neuritis (ON) as a first demyelinating event who had a median follow‐up of 4.0 years. Multiple Cox proportional‐hazards regressions revealed abnormal cranial magnet resonance imaging (cMRI; hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 3.39–10.39, p < 0.001), presence of cerebrospinal fluid immunoglobulin G oligoclonal bands (OCB; HR = 3.69, 95% CI = 2.32–5.86, p < 0.001), and age (HR = 1.08 per year of age, 95% CI = 1.02–1.13, p = 0.003) as independent predictors of conversion, whereas sex and laterality (unilateral vs bilateral) had no influence. Combined cMRI and OCB positivity indicated a 26.84‐fold higher HR for developing MS compared to double negativity (95% CI = 12.26−58.74, p < 0.001). Accordingly, cerebrospinal fluid analysis may supplement cMRI to determine the risk of MS in children with isolated ON. Ann Neurol 2015;77:1076–1082


Childs Nervous System | 2013

Updated physiology and pathophysiology of CSF circulation—the pulsatile vector theory

Matthias Preuss; Karl-Titus Hoffmann; M. Reiss-Zimmermann; Wolfgang Hirsch; Andreas Merkenschlager; Jürgen Meixensberger; M. Dengl

IntroductionHydrocephalus is still a not well-understood diagnostic and a therapeutic dilemma because of the lack of sufficient and comprehensive model of cerebrospinal fluid circulation and pathological alterations.ConclusionsBased on current studies, reviews, and knowledge of cerebrospinal fluid dynamics, brain water dynamics, intracranial pressure, and cerebral perfusion physiology, a new concept is deducted that can describe normal and pathological changes of cerebrospinal fluid circulation and pathophysiology of idiopathic intracranial hypertension.


Neurology | 2009

DEVELOPMENT OF MESIAL TEMPORAL LOBE EPILEPSY IN CHOREA-ACANTHOCYTOSIS

Rainer Scheid; Benedict Bader; Derek V. M. Ott; Andreas Merkenschlager; Adrian Danek

Chorea-acanthocytosis (ChAc) is a hereditary movement disorder that is caused by recessive mutations in the VPS13A gene on chromosome 9q21, encoding for chorein.1 Epilepsy is currently not considered a core clinical feature of ChAc, although approximately 40% of patients are affected by seizures. We report on 3 patients with mesial temporal lobe epilepsy as the first, predominant clinical indication, and in 2 of the patients so far the sole clinical symptom of the disease. For the first time in this context, a pathologic process in the medial temporal lobes, leading to hippocampal atrophy, is unequivocally documented. ### Case histories. Patient 1 was a 14-year-old boy when, after repeat epigastric sensations, a first seemingly generalized tonic-clonic seizure led to hospital admission. Several weeks prior, he had started to complain about repetitive deja vu. Repeat EEG studies most frequently showed normal 10/second alpha-, but also paroxysmal generalized theta-, right hemispheric delta-, and right temporo-occipital spike- and sharp-wave activity. Until the present, 4 years after the initial onset, 2 more tonic-clonic seizures have occurred, and, with variable frequencies, the patient continues to report rising epigastric sensations, deja vu, and amnesic auras. Medical treatment currently consists of the administration of topiramate (300 mg/day). Patient 2, the older brother of patient 1, had a first complex partial seizure at 23 years of age. His history was unremarkable; no febrile seizures had been reported. Lately, however, he has also reported repeat episodes of deja vu. EEG findings ranged from normal 9/second alpha- to intermittent and continuous spike- and sharp-wave activity over both frontotemporal regions. Apart from rare epigastric auras, the patient is presently (i.e., 8 months after his first epileptic seizure) seizure-free under levetiracetam (2,500 mg/day). Patient 3 is a 39-year-old man …


Archives of Disease in Childhood | 2015

Knowledge and attitudes of school teachers, preschool teachers and students in teacher training about epilepsy and emergency management of seizures

Henriette Karoline Dumeier; Martina Patrizia Neininger; Matthias K. Bernhard; Steffen Syrbe; Andreas Merkenschlager; Jörg Zabel; Wieland Kiess; Thilo Bertsche; Astrid Bertsche

Problem School and preschool teachers play a key role in the care of children with epilepsy. Yet, data about their knowledge on epilepsy are scarce. Methods Assessment of knowledge and attitudes towards epilepsy in teachers by conducting a questionnaire survey in Leipzig and Blankenburg, Germany, from August 2013 to January 2014. Results 1243 questionnaires were completed by 302 school teachers, 883 preschool teachers, 56 students and two unclassified participants. Of the respondents, 140 (11%) stated to have already been actively involved in an epilepsy emergency situation, another 148 (12%) as observers. Only 214 (17%) of respondents felt sufficiently prepared for an emergency. A rescue medication had already been applied by 79 (6%) of respondents; only 186 respondents (15%) stated they would be willing to administer a prescribed rescue medication under any circumstances. In response to an open-ended question about the most common fatal outcomes of a seizure, status epilepticus and drowning were rarely mentioned. 233 (19%) of respondents assumed that epileptic seizures cannot result in death. 606 (49%) of respondents were concerned about the legal repercussions to an incorrect response to a seizure.129/403 (32%) of teachers with >20 years of professional experience claimed never to have had a child suffering from epilepsy in their care, even though the prevalence of childhood epilepsy indicates that they should. In total, 1066 (86%) respondents expressed a desire to gain more knowledge on epilepsy. Conclusions Training programmes for teachers should be established. Furthermore, a clear legal regulatory framework needs to be set up.


American Journal of Medical Genetics Part A | 2007

Pulmonary artery sling and congenital tracheal stenosis in another patient with Mowat–Wilson syndrome

Sibylle Strenge; Wolfram Heinritz; Christiane Zweier; Anita Rauch; Udo Rolle; Andreas Merkenschlager; Ursula G. Froster

Sibylle Strenge,* Wolfram Heinritz, Christiane Zweier, Anita Rauch, Udo Rolle, Andreas Merkenschlager, and Ursula G. Froster Medical Faculty, Institute of Human Genetics, University of Leipzig, Leipzig, Germany Institute of Human Genetics, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany Department of Pediatric Surgery, University of Leipzig, Leipzig, Germany Hospital for Children and Adolescents, University of Leipzig, Leipzig, Germany


European Journal of Paediatric Neurology | 2016

Use of complementary and alternative medicine (CAM) by parents in their children and adolescents with epilepsy – Prevelance, predictors and parents' assessment

Nicole Hartmann; Martina Patrizia Neininger; Matthias K. Bernhard; Steffen Syrbe; Petra Nickel; Andreas Merkenschlager; Wieland Kiess; Thilo Bertsche; Astrid Bertsche

BACKGROUND The use of complementary and alternative medicine (CAM) is popular. Parents of children suffering from epilepsy may also consider administering CAM to their children. Systematic data about frequency of and motivations for CAM use, however, are scarce. METHODS In a university hospitals neuropaediatric department parents of patients aged 0-18 years suffering from epilepsy were consecutively invited to take part in a structured interview during 4 months in 2014. RESULTS Of the invited parents, 164/165 (99%) agreed to participate. From those, 21/164 (13%) stated that they used CAM in their child. The highest independent predictive value of CAM use was the occurrence of adverse drug events (ADE) of anticonvulsants as judged by parents. Patients affected by ADE had a 5.6 higher chance of receiving CAM compared to patients without ADE. Most commonly used were homeopathy (14/21, 67%) and osteopathy (12/21, 57%). The internet was the most frequently used source of information (14/21, 67%). Of the parents, 10/21 (48%) described positive effects of CAM on seizure frequency, 12/21 (57%) on general condition of their child, and 20/21 (95%) wished to continue CAM for epilepsy therapy. From the non-users of CAM, 91/143 (66%) expressed the desire to learn more about CAM for epilepsy therapy. LIMITATIONS Our study was performed in a university hospital in a large urban city in Eastern Germany. CAM user rates can differ in other parts of Germany and Europe, in other institutions and for chronic diseases other than epilepsy. CONCLUSION The main reason for CAM use was the occurrence of ADE of anticonvulsants. More than half of the parents saw a benefit of CAM for their children. Almost all parents wished to continue CAM use, even those who did not see concrete positive effects.


Brain & Development | 2014

Wide spectrum of clinical manifestations in children with tuberous sclerosis complex – Follow-up of 20 children

Roland R. Mettin; Andreas Merkenschlager; Matthias K. Bernhard; Heidrun Elix; Wolfgang Hirsch; Wieland Kiess; Steffen Syrbe

UNLABELLED TSC is a multisystem genetic disorder predisposing to multiple organ manifestations and developmental problems. Clinical follow-up of patients remains a challenge for the caring paediatrician. METHODS We performed a retrospective analysis of clinical manifestations, diagnostic and therapeutic data in 20 children with the diagnosis of tuberous sclerosis complex (TSC) to answer the following questions: are the clinical guidelines and imaging strategies appropriate to discover complications, are there significant early predictors of long-term prognosis, what is the age range for signs and symptoms to occur. RESULTS Cardiac rhabdomyoma were present in 18 children and occurred as earliest manifestation. 8 of these exhibited associated arrhythmia or congenital cardiac anomalies. Seizures combined with cortical tubers and subependymal nodules occurred in 18 patients and were most likely to start in infancy, which was associated with later cognitive impairment. Cutaneous manifestations (15 children) occurred in late childhood and school age, whilst renal angiomyolipomas (11) developed in puberty. DISCUSSION The clinical course and imaging strategies are compared with data from previous studies. A review of TSC in regard to the multiple manifestations is provided.

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Wolfgang Hirsch

Martin Luther University of Halle-Wittenberg

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