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Lafora disease (LD; OMIM#274780) is a fatal rare neurodegenerative disorder characterized by generalized epileptic seizures and the presence of polyglucosan inclusions (PGs), called Lafora bodies (LBs), typically in the brain. LD is caused by mutations in two genes EPM2A or EPM2B, which encode respectively laforin, a glucan phosphatase, and malin, an E3-ubiquitin ligase. Much remains unknown about the molecular bases of LD and, unfortunately, appropriate treatment is still missing; therefore patients die within 10 years from the onset of the disease. Recently, we have identified neuroinflammation as one of the initial determinants in LD. In this work, we have investigated anti-inflammatory treatments as potential therapies in LD. With this aim, we have performed a preclinical study in an Epm2b-/- mouse model with propranolol, a β-adrenergic antagonist, and epigallocatechin gallate (EGCG), an antioxidant from green tea extract, both of which displaying additional anti-inflammatory properties. In vivo motor and cognitive behavioral tests and ex vivo histopathological brain analyses were used as parameters to assess the therapeutic potential of propranolol and EGCG. After 2 months of treatment, we observed an improvement not only in attention defects but also in neuronal disorganization, astrogliosis, and microgliosis present in the hippocampus of Epm2b-/- mice. In general, propranolol intervention was more effective than EGCG in preventing the appearance of astrocyte and microglia reactivity. In summary, our results confirm the potential therapeutic effectiveness of the modulators of inflammation as novel treatments in Lafora disease.

Lafora disease (LD) is one of the progressive and fatal forms of a neurodegenerative disorder and is characterized by teenage-onset myoclonic seizures. Neuropathological changes in LD include the formation of abnormal glycogen as Lafora bodies, gliosis, and neuroinflammation. LD is caused by defects in the gene coding for phosphatase (laforin) or ubiquitin ligase (malin). Mouse models of LD, developed by targeted disruption of these two genes, develop most symptoms of LD and show increased susceptibility to induced seizures. Studies on mouse models also suggest that defective autophagy might contribute to LD etiology. In an attempt to understand the specific role of autophagy in LD pathogenesis, in this study, we fed LD animals with trehalose, an inducer of autophagy, for 3 months and looked at its effect on the neuropathology and seizure susceptibility. We demonstrate here that trehalose ameliorates gliosis, neuroinflammation, and endoplasmic reticulum stress and reduces susceptibility to induced seizures in LD animals. However, trehalose did not affect the formation of Lafora bodies, suggesting the epileptic phenotype in LD could be either secondary to or independent of Lafora bodies. Taken together, our results suggest that autophagy inducers can be considered as potential therapeutic molecules for Lafora disease.

Perampanel is an α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist that has been marked as an antiepileptic drug for partial-onset and primary generalized tonic-clonic seizures. There have been some recent reports of perampanel being effective against cortical myoclonus by Lafora disease and Unverricht-Lundborg disease. We herein report a 49-year-old man who presented with myoclonus due to Lance-Adams syndrome (LAS) after cardiopulmonary arrest caused by a severe bronchial asthma attack. Perampanel was very effective against myoclonus induced by LAS even in the chronic state, over 10 years after the remote onset. Perampanel should be considered for the treatment of extremely refractory myoclonus due to LAS.

Progressive myoclonic epilepsy (PME) is a progressive neurological disorder. Unfortunately, until now, no definitive curative treatment exists; however, it is of utmost importance to identify patients with PME. The underlying aetiology can be pinpointed if methodological clinical evaluation is performed, followed by subsequent genetic testing. We report a case of PME that was diagnosed as Lafora body disease. This case emphasises that, suspecting and identifying PME is important so as to start appropriate treatment and reduce the probability of morbidity and prognosticate the family., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

We report the atypical presentation of Lafora disease in a Senegalese girl carrying the homozygous variant, c.560A>C, in the NHLRC1 gene. At 13 years, the patient developed myoclonic and visual seizures, progressive psychomotor slowing, and cognitive decline. At 14 years, a neurological examination showed severe hypomimia, bradykinesia, rigidity and low-amplitude myoclonic jerks. Flash-visual and somatosensory evoked potentials showed an increased amplitude of the cortical components, while an electroretinogram showed attenuated responses. An EEG showed diffuse polyspikes associated with positive-negative jerks as well as posterior slow waves and irregular spikes. The electroclinical picture suggested the diagnosis of Lafora disease regarding the association of visual seizures, cognitive deterioration, and action myoclonus, together with the EEG and evoked potential findings. Two uncommon findings were the prominence of extrapyramidal signs in the early stage of disease (which are rarely reported) and attenuation of electroretinal responses. We consider that Lafora disease should be included in the diagnostic work-up for juvenile Parkinsonism, when associated with epilepsy.

A young man with normal neurodevelopment presented with 3 years of medically refractory, progressive epilepsy and myoclonus. Initial examination included neuroimaging, electroencephalography, and biochemical analyses, all of which were unremarkable except for mildly enlarged ventricles. Over the following year, the patient experienced rapid cognitive decline with new-onset recurrent visual hallucinations and progressive lethargy. Results of subsequent electroencephalography and brain imaging were unchanged, and a fluorodeoxyglucose F 18 positron emission tomographic scan was normal.

Objective: To search for new therapies aimed at ameliorating the neurologic symptoms and epilepsy developing in patients with Lafora disease., Methods: Lafora disease is caused by loss-of-function mutations in either the EPM2A or EPM2B genes. Epm2a -/- and Epm2b -/- mice display neurologic and behavioral abnormalities similar to those found in patients. Selenium is a potent antioxidant and its deficiency has been related to the development of certain diseases, including epilepsy. In this study, we investigated whether sodium selenate treatment improved the neurologic alterations and the hyperexcitability present in the Epm2b -/- mouse model., Results: Sodium selenate ameliorates some of the motor and memory deficits and the sensitivity observed with pentylenetetrazol (PTZ) treatments in Epm2b -/- mice. Neuronal degeneration and gliosis were also diminished after sodium selenate treatment., Significance: Sodium selenate could be beneficial for ameliorating some symptoms that present in patients with Lafora disease., (Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.)

Background: Lafora disease is a rare, autosomal recessive, progressive myoclonic epilepsy with onset typically in the second decade of life and uniformly fatal outcome. Most of the current literature focuses on diagnosis, genetic basis, neurological signs, and possible treatment of this currently incurable disease. On literature review of over 50 articles including over 300 patients, there were no comments on or pathologic description of endocrinologic issues in relation to Lafora disease., Patient Description: We describe a patient with Lafora disease with severe neurological deterioration. During hospitalization for urosepsis, he exhibited thyrotoxicosis with a free thyroxine (T4) level greater than 7.77 ng/dL. On autopsy, he had lymphocytic thyroiditis and Lafora bodies throughout his organs including the anterior pituitary, hypothalamus, and pancreas., Conclusions: This is the first report of the pathologic findings of Lafora bodies in endocrine organs. Although this patient's thyrotoxic state was likely not a direct result of his Lafora disease, given the diffuse deposition of Lafora bodies, endocrinologic abnormalities should be considered in patients with Lafora disease. Furthermore, acute decompensation in these individuals may arise not from a declining neurological status but from a coincidental disease process., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Epilepsy is a heterogeneous group of disorders, often associated with significant comorbidity, such as intellectual disability and skin disorder. The genetic underpinnings of many epilepsies are still being elucidated, and we expect further advances over the coming 5 years, as genetic technology improves and prices fall for whole exome and whole genome sequencing. At present, there are several well-characterized complex epilepsies associated with single gene disorders; we review some of these here. They include well-recognized syndromes such as tuberous sclerosis complex, epilepsy associated with Rett syndrome, some of the progressive myoclonic epilepsies, and novel disorders such as epilepsy associated with mutations in the PCDH 19 gene. These disorders are important in informing genetic testing to confirm a diagnosis and to permit better understanding of the variability in phenotype-genotype correlation., (Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.)

Lafora disease is a progressive myoclonus epilepsy caused by mutations in the EPM2A gene encoding laforin or in the EPM2B gene encoding malin. It is characterized by the presence of polyglucosan intracellular inclusion bodies (Lafora bodies) in brain and other tissues. Targeted disruption of Epm2a or Epm2b genes in mice produced widespread neuronal degeneration and accumulation of Lafora bodies in neuronal and nonneuronal tissues. Here we analyzed the neurologic alterations produced by disruption of the laforin gene in Epm2a mice and compared them to those in malin-deficient mice. Both Epm2a and Epm2b mice showed altered motor activity, impaired motor coordination, abnormal hind limb clasping, and episodic memory deficits. Epm2a mice also had tonic-clonic seizures, whereas both Epm2a and Epm2b mice had spontaneous single spikes, spike-wave, polyspikes, and polyspike-wave complexes with correlated myoclonic jerks. Neurologic alterations observed in the mutants were comparable and correlated with the accumulation of abundant Lafora bodies in the cerebral cortex, the hippocampus, the basal ganglia, the cerebellum, and the brainstem, suggesting that these inclusions could cause cognitive and behavioral deterioration. Thus, both Epm2a and Epm2b mice exhibit many pathologic aspects seen in patients with Lafora disease and may be valuable for the study of this disorder.

Objective: Glycogen, the largest cytosolic macromolecule, acquires solubility, essential to its function, through extreme branching. Lafora bodies are aggregates of polyglucosan, a long, linear, poorly branched, and insoluble form of glycogen. Lafora bodies occupy vast numbers of neuronal dendrites and perikarya in Lafora disease in time-dependent fashion, leading to intractable and fatal progressive myoclonus epilepsy. Lafora disease is caused by deficiency of either the laforin glycogen phosphatase or the malin E3 ubiquitin ligase. The 2 leading hypotheses of Lafora body formation are: (1) increased glycogen synthase activity extends glycogen strands too rapidly to allow adequate branching, resulting in polyglucosans; and (2) increased glycogen phosphate leads to glycogen conformational change, unfolding, precipitation, and conversion to polyglucosan. Recently, it was shown that in the laforin phosphatase-deficient form of Lafora disease, there is no increase in glycogen synthase, but there is a dramatic increase in glycogen phosphate, with subsequent conversion of glycogen to polyglucosan. Here, we determine whether Lafora bodies in the malin ubiquitin ligase-deficient form of the disease are due to increased glycogen synthase or increased glycogen phosphate., Methods: We generated malin-deficient mice and tested the 2 hypotheses., Results: Malin-deficient mice precisely replicate the pathology of Lafora disease with Lafora body formation in skeletal muscle, liver, and brain, and in the latter in the pathognomonic perikaryal and dendritic locations. Glycogen synthase quantity and activity are unchanged. There is a highly significant increase in glycogen phosphate., Interpretation: We identify a single common modification, glycogen hyperphosphorylation, as the root cause of Lafora body pathogenesis.

We report a patient with congenital generalized lipodystrophy who had suffered from seizures, myoclonus, ataxia and cognitive decline since late childhood. Lafora disease was diagnosed based on skin biopsy results, which revealed pathognomonic Lafora bodies. The results of genetic analysis for mutations in EPM2A and EPM2B genes were negative. This is the first case report describing an association between congenital generalized lipodystrophy and Lafora disease. Further studies focusing on the relationship between these two diseases and the identification of a third locus for Lafora disease are needed.

Background: Lafora disease (LD; progressive myoclonus epilepsy type 2; EPM2) is an autosomal recessive disorder caused by mutations in the EPM2A and EPM2B genes. LD is characterized by the presence of strongly PAS-positive intracellular inclusions (Lafora bodies) in several tissues. Glycogen storage disease type IV (GSD-IV; Andersen disease) is an autosomal recessive disorder characterized by cirrhosis leading to severe liver failure. GSD-IV has been associated with mutations in the glycogen branching enzyme gene (GBE). Histopathologic changes of the liver in both diseases show an identical appearance, although cirrhosis has never been described in patients with LD. We report a LD family in which the proband presented severe liver failure at onset of the disease., Methods: Clinical histories, physical and neurologic examination, laboratory tests, EEGs, MRI of the brain, and liver or axillary skin biopsies were performed in the two affected siblings. The diagnosis was confirmed by molecular genetic analysis of the EPM2A, EPM2B, and GBE genes and loci., Results: During the first decade of life, abnormalities in liver function tests were detected in the two affected siblings. The proband's liver dysfunction was severe enough to require liver transplantation. Subsequently, both sibs developed LD. Mutation analysis of EPM2A revealed a homozygous Arg241stop mutation in both patients., Conclusions: This is the first description of severe hepatic dysfunction as the initial clinical manifestation of LD. The phenotypic differences between the two affected siblings suggest that modifier genes must condition clinical expression of the disease outside the CNS.

The authors report a patient with Lafora disease, whose myoclonus was suppressed by passive eye closure. Neurophysiologic studies disclosed that fixation was the most important enhancer of myoclonus. Magnetoencephalographic studies of visual evoked fields revealed abnormal activation of the visual corticocortical pathway via the insular cortex not seen in controls. The authors hypothesize that abnormal activation of the insular cortex may be involved in triggering the mechanism of fixation-sensitive myoclonus.

Purpose: Lafora body disease (LBD) is severe and rapidly worsening progressive myoclonus epilepsy (PME), not treatable with specific therapy. In LBD patients, typical polyglucosan accumulations result from alterations of proteins involved in the regulation of glycogen metabolism. Thus, a ketogenic regimen might reasonably be expected to counteract the disease progression. We set out to assess the feasibility and tolerability of a long-term ketogenic diet (KD) in LBD patients and to make a preliminary evaluation of its effect on the disease course., Methods: We treated five LBD patients with KD and evaluated the changes in the clinical, neuropsychological and neurophysiological findings over 10-30 months., Results: The KD was well tolerated in all the patients for the first 16 months. Nutritional measures and laboratory findings remained substantially stable. The disease progressed in all the patients, reaching an advanced stage in one. Electrophysiological findings indicated the presence of increased cortical excitability in four patients, paralleling the worsening of the myoclonus., Conclusion: KD was unable to stop the disease progression. However, given the considerable heterogeneity of the natural history of LBD, we cannot exclude the possibility that KD has the potential to slow down the disease progression. The application of this nutritional approach should be further evaluated in larger case series.

The progressive myoclonic epilepsies (PMEs) are a group of symptomatic generalised epilepsies caused by rare disorders, most of which have a genetic component, a debilitating course, and a poor outcome. Challenges with PME arise from difficulty with diagnosis, especially in the early stages of the illness, and further problems of management and drug treatment. Recent advances in molecular genetics have helped achieve better understanding of the different disorders that cause PME. We review the PMEs with emphasis on updated genetics, diagnosis, and therapeutic options.

Introduction: Lafora s disease is a type of progressive myoclonic epilepsy with poor prognosis, is characterized by myoclonic crisis, tonic clonic seizures, absence or partial complex seizures and other neurological manifestations with a progressive course and a poor response to the treatment. It has not been considered as a cause of epileptic status., Case Reports: Two women without important past medical history with normal psychomotor development before their suffering, with manifestations of 2 years of evolution the first one and 8 years on the second case characterized by myoclonic generalized, partial complex seizures and progressive deterioration of the mental functions that joined to our institution in a non convulsive epileptic status and they featured with a different evolution. The first patient with favorable control of the event with a single medication and functionality recover later, the second one with torpid evolution complicated with an epileptic status convulsive widespread condition and a prolonged permanency in the unit of intensive therapy. In both patients the diagnosis of Lafora s disease was established based in the findings of the skin axilar biopsy., Discussion and Conclusion: We believe that Lafora s disease must be suspected as a probable cause of non convulsive epileptic status in patients with myoclonic epilepsy associated with other neurological manifestations and a refractary response to the medical treatment. The evolution and clinical response will depend on the evolutionary stage of the disease.

Unlabelled: Lafora-body disease (LBD) is a rare neurometabolic disorder of autosomal recessive inheritance associated with progressive myoclonic epilepsy. We report here the first description of ictal and interictal recording by electroencephalography (EEG) and magnetoencephalography (MEG) of a 15-y-old girl suffering from LBD., Conclusions: Complementary use of MEG and EEG might be of future help to the clinician in better defining the pathophysiology of complex seizures, and also in patients with progressive neurological disorders, despite the poor prognosis of syndromes such as LBD.

Lafora's disease is a progressive myoclonus epilepsy with onset in adolescence and a gradual decline in cognitive functions and increase in seizure intractability. We present the case of a 16-year-old with precipitous dementia within 6 months of onset. Peripheral biopsies and EPM2A mutation analysis were negative. The diagnosis could be established only by brain biopsy.

Two cases of Lafora's disease with prominent movement disorders portraying rare initial manifestations are reported. In both patients, the first manifestations were cerebellar ataxia, dysartria and startle phenomenon. These symptoms occurred before seizures, myoclonic and progressive dementia, which are more well known as manifestations of Lafora's disease. The diagnosis was confirmed by the identification of PAS positive inclusion bodies in deep skin biopsy samples. Our patients presented an unexpected slow progression of the disease, with longer survival. Lafora's disease should be remembered among diseases causing slowly progressive ataxia associated with epileptic seizures.

Progressive myoclonic epilepsies are rare, genetically transmitted diseases characterized by epileptic seizures, myoclonus, and progressive neurologic deterioration. Unverricht-Lundborg disease, Lafora's disease, neuronal ceroid lipofuscinosis, mitochondrial disorders, and sialidosis are included in this group. Lafora's disease is a progressive disorder of the central nervous system with onset in the late first or second decade of life and is inherited in an autosomal-recessive pattern. The first clinical manifestation is generalized tonic-clonic seizures, myoclonus, or both, usually seen between the ages of 11 and 18 years. The other clinical manifestations are progressive dementia and limb ataxia. Diagnosis is based on showing the typical inclusions in the brain, liver, skin, or muscle tissue specimens. The case of a 6-year-old male patient, who was admitted with the clinical findings of third-degree atrioventricular block and dementia and eventually diagnosed with Lafora's disease, is presented.

Eleven epileptic men who complained of epilepsy and sexual dysfunction were submitted to a multidisciplinary evaluation. Mean age was 27 years (20-34), mean epilepsy duration was 19 years (0.5-32) and the mean seizure frequency was two by week (0-7). Ten patients had partial seizures and one other had myoclonic epilepsy. Ten patients were treated with antiepileptic drugs (phenytoin--1, carbamazepine--8, clonazepam--3, clobazam--2, valproic acid--3, vigabatrin--1). As defined in the DSM III-R, the complaints were: erectile disorder (9), hypoactive sexual desire disorder (4), frotteurism (4), inhibited orgasm (3), premature ejaculation (3), fetishism (2), voyeurism (2), exhibitionism (2), pedophilia (1) and sexual aversion disorder (1). Two patients showed hypogonadotropic hypogonadism on endocrinologic screening. Urological evaluation disclosed organic erectile dysfunction in other two. One patient had a diagnosis of psychogenic sexual disorder. In six patients a conclusive etiologic diagnosis was not reached. This report shows the multifactorial nature of sexual disorder in epilepsy and underlies the need of a multidisciplinar evaluation.

A case is described in which non-convulsive status epilepticus (NCSE) prompted further investigation leading to the diagnosis of Lafora body disease (LBD). The onset of NCSE was temporally related to the withdrawal of sodium valproate and introduction of carbamazepine, which may have been precipitating factors. NCSE has not previously been reported in LBD. Implications for its drug management are discussed., (Copyright 1999 Lippincott Williams & Wilkins.)