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Goebel HH, Stenzel W. A brief history of the congenital myopathies - the myopathological perspective. Neuromuscul Disord 2023; 33:990-995. [PMID: 37980206 DOI: 10.1016/j.nmd.2023.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/23/2023] [Accepted: 10/13/2023] [Indexed: 11/20/2023]
Abstract
Congenital myopathies are defined by early clinical onset, slow progression, hereditary nature and disease-specific myopathological lesions - however, with exceptions - demanding special techniques in regard to morphological diagnostic and research work-up. To identify an index disease in a family requires a muscle biopsy - and no congenital myopathy has ever been first described at autopsy. The nosographic history commenced when - in addition to special histopathological techniques in the earliest classical triad of central core disease, 1956, nemaline myopathy, 1963, and centronuclear myopathy, 1966/67, within a decade - electron microscopy and enzyme histochemistry were applied to unfixed frozen muscle tissue and, thus, revolutionized diagnostic and research myopathology. During the following years, the list of structure-defined congenital myopathies grew to some 40 conditions. Then, the introduction of immunohistochemistry allowed myopathological documentation of proteins and their abnormalities in individual congenital myopathies. Together with the diagnostic evolution of molecular genetics, many more congenital myopathies were described, without new disease-specific lesions or only already known ones. These were nosographically defined by individual mutations in hitherto congenital myopathies-unrelated genes. This latter development may also affect the nomenclature of congenital myopathies in that the mutant gene needs to be attached to the individually identified congenital myopathies with or without the disease-specific lesion, such as CCD-RYR1 or CM-RYR1. This principle is similar to that of the nomenclature of Congenital Disorders of Glycosylation. Retroactive molecular characterization of originally and first described congenital myopathies has only rarely been achieved.
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Affiliation(s)
- Hans H Goebel
- Institute of Neuropathology, Charite Universitätsmedizin, Berlin, Germany; Department of Neuropathology, Universitätsmedizin, Mainz, Germany.
| | - Werner Stenzel
- Institute of Neuropathology, Charite Universitätsmedizin, Berlin, Germany
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Goebel HH, Stenzel W. Josef Godwin Greenfield as a myopathologist and his myopathological legacy. Neuromuscul Disord 2023; 33:882-883. [PMID: 37923655 DOI: 10.1016/j.nmd.2023.09.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 09/29/2023] [Indexed: 11/07/2023]
Affiliation(s)
- Hans H Goebel
- Department of Neuropathology, Charité - Universitätsmedizin, Berlin, Germany; Department of Neuropathology, Universitätsmedizin, Mainz, Germany.
| | - Werner Stenzel
- Department of Neuropathology, Charité - Universitätsmedizin, Berlin, Germany
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3
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Komisarek O, Malak R, Kwiatkowski J, Wiecheć K, Szczapa T, Kasperkowicz J, Matthews-Kozanecka M, Matthews-Brzozowska T, Wójcik M, Samborski W, Mojs E. The Evaluation of Facial Muscles by Surface Electromyography in Very Preterm Infants. Biomedicines 2022; 10:biomedicines10112921. [PMID: 36428488 PMCID: PMC9687131 DOI: 10.3390/biomedicines10112921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 11/11/2022] [Accepted: 11/11/2022] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND It is reported that 40% of preterm infants have problems with eating. Neonatal feeding disorders may be one of the factors increasing neonatal mortality. The aim of our study was to evaluate the muscles involved in suckling and swallowing in premature newborns using surface electromyography (sEMG). We would like to objectively describe the tension of muscles engaged in feeding in order to properly plan the therapy. Another aim was to compare sEMG measurements to gestational age, birth weight, and umbilical blood pH to show which parameters put children at risk of feeding problems. METHODS Sixteen preterm neonates with gestational age less than 32 weeks, birth weight less than 1500 g, and oral feeding difficulties were analyzed for muscle response and electrical activity of nerves using sEMG (surface electromyography). RESULTS We found a negative correlation indicating that preterm infants with a younger gestational age had higher suprahyoid muscle tension, and a positive correlation was found between pH value and suprahyoid muscles. The lower the pH value, the lower the tension in the suprahyoid muscles. CONCLUSIONS sEMG may be a helpful diagnostic tool in the evaluation of the masticatory system of premature infants. Due to the abnormal tone of the muscles responsible for swallowing, it is advisable to rehabilitate as early as possible.
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Affiliation(s)
- Oskar Komisarek
- Department of Plastic, Reconstructive and Aesthetic Surgery, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Torun, 85-821 Bydgoszcz, Poland
- Correspondence: (O.K.); (R.M.)
| | - Roksana Malak
- Department and Clinic of Rheumatology, Rehabilitation and Internal Medicine, Poznań University of Medical Sciences, 61-545 Poznań, Poland
- Correspondence: (O.K.); (R.M.)
| | - Jacek Kwiatkowski
- Students Scientific Society of Maxillofacial Orthopaedics and Orthodontics, University of Medical Sciences, 60-812 Poznań, Poland
| | - Katarzyna Wiecheć
- Department of Clinical Psychology, Poznań University of Medical Sciences, 60-812 Poznań, Poland
| | - Tomasz Szczapa
- Neonatal Biophysical Monitoring and Cardiopulmonary Therapies Research Unit, II Department of Neonatology, Poznan University of Medical Sciences, 60-535 Poznan, Poland
| | - Joanna Kasperkowicz
- Department and Clinic of Rheumatology, Rehabilitation and Internal Medicine, Poznań University of Medical Sciences, 61-545 Poznań, Poland
| | - Maja Matthews-Kozanecka
- Department of Social Sciences and the Humanities, Poznan University of Medical Sciences, 60-806 Poznań, Poland
| | - Teresa Matthews-Brzozowska
- Department of Orthodontics and Masticatory System Dysfunction, Poznan University of Medical Sciences, 60-812 Poznań, Poland
| | - Małgorzata Wójcik
- Department of Physiotherapy, Faculty of Physical Culture in Gorzów Wielkopolski, Poznan University of Physical Education, Estkowskiego 13, 66-400 Gorzów Wielkopolski, Poland
| | - Włodzimierz Samborski
- Department and Clinic of Rheumatology, Rehabilitation and Internal Medicine, Poznań University of Medical Sciences, 61-545 Poznań, Poland
| | - Ewa Mojs
- Department of Clinical Psychology, Poznań University of Medical Sciences, 60-812 Poznań, Poland
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Topaloglu H. Core myopathies - a short review. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39:266-273. [PMID: 33458581 PMCID: PMC7783431 DOI: 10.36185/2532-1900-029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 11/18/2020] [Indexed: 12/01/2022]
Abstract
Congenital myopathies represent a clinically and genetically heterogeneous group of early-onset neuromuscular diseases with characteristic, but not always specific, histopathological features, often presenting with stable and/or slowly progressive truncal and proximal weakness. It is often not possible to have a diagnosis on clinical ground alone. Additional extraocular, respiratory, distal involvement, scoliosis, and distal laxity may provide clues. The "core myopathies" collectively represent the most common form of congenital myopathies, and the name pathologically corresponds to histochemical appearance of focally reduced oxidative enzyme activity and myofibrillar changes on ultrastructural studies. Because of the clinical, pathological, and molecular overlaps, central core disease and multiminicore disease will be discussed together.
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Affiliation(s)
- Haluk Topaloglu
- Correspondence Haluk Topaloglu Yeditepe University Department of Pediatrics, İstanbul, Turkey. E-mail:
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Lawal TA, Todd JJ, Witherspoon JW, Bönnemann CG, Dowling JJ, Hamilton SL, Meilleur KG, Dirksen RT. Ryanodine receptor 1-related disorders: an historical perspective and proposal for a unified nomenclature. Skelet Muscle 2020; 10:32. [PMID: 33190635 PMCID: PMC7667763 DOI: 10.1186/s13395-020-00243-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 08/18/2020] [Indexed: 12/14/2022] Open
Abstract
The RYR1 gene, which encodes the sarcoplasmic reticulum calcium release channel or type 1 ryanodine receptor (RyR1) of skeletal muscle, was sequenced in 1988 and RYR1 variations that impair calcium homeostasis and increase susceptibility to malignant hyperthermia were first identified in 1991. Since then, RYR1-related myopathies (RYR1-RM) have been described as rare, histopathologically and clinically heterogeneous, and slowly progressive neuromuscular disorders. RYR1 variants can lead to dysfunctional RyR1-mediated calcium release, malignant hyperthermia susceptibility, elevated oxidative stress, deleterious post-translational modifications, and decreased RyR1 expression. RYR1-RM-affected individuals can present with delayed motor milestones, contractures, scoliosis, ophthalmoplegia, and respiratory insufficiency. Historically, RYR1-RM-affected individuals were diagnosed based on morphologic features observed in muscle biopsies including central cores, cores and rods, central nuclei, fiber type disproportion, and multi-minicores. However, these histopathologic features are not always specific to RYR1-RM and often change over time. As additional phenotypes were associated with RYR1 variations (including King-Denborough syndrome, exercise-induced rhabdomyolysis, lethal multiple pterygium syndrome, adult-onset distal myopathy, atypical periodic paralysis with or without myalgia, mild calf-predominant myopathy, and dusty core disease) the overlap among diagnostic categories is ever increasing. With the continuing emergence of new clinical subtypes along the RYR1 disease spectrum and reports of adult-onset phenotypes, nuanced nomenclatures have been reported (RYR1- [related, related congenital, congenital] myopathies). In this narrative review, we provide historical highlights of RYR1 research, accounts of the main diagnostic disease subtypes and propose RYR1-related disorders (RYR1-RD) as a unified nomenclature to describe this complex and evolving disease spectrum.
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Affiliation(s)
- Tokunbor A Lawal
- Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, USA.
| | - Joshua J Todd
- Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, USA
| | - Jessica W Witherspoon
- Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, USA
| | - Carsten G Bönnemann
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - James J Dowling
- Departments of Paediatrics and Molecular Genetics, Hospital for Sick Children and University of Toronto, Toronto, Canada
| | - Susan L Hamilton
- Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX, USA
| | - Katherine G Meilleur
- Tissue Injury Branch, National Institute of Nursing Research, National Institutes of Health, Bethesda, MD, USA
| | - Robert T Dirksen
- Department of Pharmacology and Physiology, University of Rochester Medical Center, Rochester, NY, USA
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6
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Wang Q, Hu Z, Chang X, Yu M, Xie Z, Lv H, Zhang W, Xiong H, Yuan Y, Wang Z. Mutational and clinical spectrum in a cohort of Chinese patients with hereditary nemaline myopathy. Clin Genet 2020; 97:878-889. [PMID: 32222963 DOI: 10.1111/cge.13745] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/23/2020] [Accepted: 03/23/2020] [Indexed: 12/12/2022]
Abstract
Hereditary nemaline myopathy (NM) is one of the most common congenital myopathies with the histopathological findings of nemaline bodies. We used targeted next-generation sequencing to identify causative mutations in 48 NM patients with confirmed myopathological diagnosis, analyze the mutational spectrum and phenotypic features. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) was used to confirm the pathogenic effect of one nebulin (NEB) splicing variant. The results showed that variants were found in five NM-associated genes, including NEB, actin alpha 1 (ACTA1), troponin T1, Kelch repeat and BTB domain-containing 13, and cofilin-2, in 34 (73.9%), 7 (15.2%), 3 (6.5%), 1 (2.2%), and 1 (2.2%) patients, respectively, in a total of 46/48 (95.8%) NM patients. Of the total 64 variants identified, 51 were novel variants including 26 pathogenic, 1 probably pathogenic, and 24 variant of uncertain significance (VUS). Notably, one NEB splicing mutation, c.21417+3A>G causing exon 144 splicing (NM_001164508.1), as confirmed by RT-PCR, was found in 52.9% (18 patients) of NEB variant-carrying patients. Typical congenital NM, the most common clinical subtype (60.4%), was associated with five NM genes. We concluded that hereditary NM showed a highly variable genetic spectrum. NEB was the most frequent causative gene in this Chinese cohort, followed by ACTA1. We found a hotspot splicing mutation in NEB among Chinese cohort.
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Affiliation(s)
- Qi Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhenxian Hu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Xingzhi Chang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Meng Yu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhiying Xie
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - He Lv
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
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Fox MD, Carson VJ, Feng HZ, Lawlor MW, Gray JT, Brigatti KW, Jin JP, Strauss KA. TNNT1 nemaline myopathy: natural history and therapeutic frontier. Hum Mol Genet 2019; 27:3272-3282. [PMID: 29931346 DOI: 10.1093/hmg/ddy233] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/06/2018] [Indexed: 02/03/2023] Open
Abstract
We describe the natural history of 'Amish' nemaline myopathy (ANM), an infantile-onset, lethal disease linked to a pathogenic c.505G>T nonsense mutation of TNNT1, which encodes the slow fiber isoform of troponin T (TNNT1; a.k.a. TnT). The TNNT1 c.505G>T allele has a carrier frequency of 6.5% within Old Order Amish settlements of North America. We collected natural history data for 106 ANM patients born between 1923 and 2017. Over the last two decades, mean age of molecular diagnosis was 16 ± 27 days. TNNT1 c.505G>T homozygotes were normal weight at birth but failed to thrive by age 9 months. Presenting neonatal signs were axial hypotonia, hip and shoulder stiffness, and tremors, followed by progressive muscle weakness, atrophy and contractures. Affected children developed thoracic rigidity, pectus carinatum and restrictive lung disease during infancy, and all succumbed to respiratory failure by 6 years of age (median survival 18 months, range 0.2-66 months). Muscle histology from two affected children showed marked fiber size variation owing to both Type 1 myofiber smallness (hypotrophy) and Type 2 fiber hypertrophy, with evidence of nemaline rods, myofibrillar disarray and vacuolar pathology in both fiber types. The truncated slow TNNT1 (TnT) fragment (p.Glu180Ter) was undetectable in ANM muscle, reflecting its rapid proteolysis and clearance from sarcoplasm. Similar functional and histological phenotypes were observed in other human cohorts and two transgenic murine models (Tnnt1-/- and Tnnt1 c.505G>T). These findings have implications for emerging molecular therapies, including the suitably of TNNT1 gene replacement for newborns with ANM or other TNNT1-associated myopathies.
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Affiliation(s)
- Michael D Fox
- Clinic for Special Children, Strasburg, PA, USA
- Department of Pediatrics, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA
- Diagnostic Referral Division, Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | | | - Han-Zhong Feng
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
| | - Michael W Lawlor
- Department of Pathology and Laboratory Medicine and Neuroscience Research Center, The Medical College of Wisconsin, Milwaukee, WI, USA
| | - John T Gray
- Audentes Therapeutics, San Francisco, CA, USA
| | | | - J-P Jin
- Department of Physiology, Wayne State University School of Medicine, Detroit, MI, USA
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8
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Konersman CG, Freyermuth F, Winder TL, Lawlor MW, Lagier‐Tourenne C, Patel SB. Novel autosomal dominant TNNT1 mutation causing nemaline myopathy. Mol Genet Genomic Med 2017; 5:678-691. [PMID: 29178646 PMCID: PMC5702563 DOI: 10.1002/mgg3.325] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/13/2017] [Accepted: 07/18/2017] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Nemaline myopathy (NEM) is one of the three major forms of congenital myopathy and is characterized by diffuse muscle weakness, hypotonia, respiratory insufficiency, and the presence of nemaline rod structures on muscle biopsy. Mutations in troponin T1 (TNNT1) is 1 of 10 genes known to cause NEM. To date, only homozygous nonsense mutations or compound heterozygous truncating or internal deletion mutations in TNNT1 gene have been identified in NEM. This extended family is of historical importance as some members were reported in the 1960s as initial evidence that NEM is a hereditary disorder. METHODS Proband and extended family underwent Sanger sequencing for TNNT1. We performed RT-PCR and immunoblot on muscle to assess TNNT1 RNA expression and protein levels in proband and father. RESULTS We report a novel heterozygous missense mutation of TNNT1 c.311A>T (p.E104V) that segregated in an autosomal dominant fashion in a large family residing in the United States. Extensive sequencing of the other known genes for NEM failed to identify any other mutant alleles. Muscle biopsies revealed a characteristic pattern of nemaline rods and severe myofiber hypotrophy that was almost entirely restricted to the type 1 fiber population. CONCLUSION This novel mutation alters a residue that is highly conserved among vertebrates. This report highlights not only a family with autosomal dominant inheritance of NEM, but that this novel mutation likely acts via a dominant negative mechanism.
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Affiliation(s)
| | - Fernande Freyermuth
- MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusetts
- Broad Institute of Harvard University and MITCambridgeMassachusetts
| | - Thomas L. Winder
- Prevention GeneticsMarshfieldWisconsin
- Present address:
Invitae CorporationSan FranciscoCalifornia
| | - Michael W. Lawlor
- Division of Pediatric PathologyDepartment of Pathology and Laboratory Medicine and Neuroscience Research CenterMedical College of WisconsinMilwaukeeWisconsin
| | - Clotilde Lagier‐Tourenne
- MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMassachusetts
- Broad Institute of Harvard University and MITCambridgeMassachusetts
| | - Shailendra B. Patel
- Division of EndocrinologyMetabolism and Clinical NutritionMedical College of Wisconsin, and Clement J. Zablocki VAMCMilwaukeeWisconsin
- Present address:
Division of Endocrinology, Diabetes and MetabolismUniversity of CincinnatiCincinnatiOhio
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DICHIRO G, NELSON KB. Soft Tissue Radiography of Extremities in Neuromuscular Disease with Histological Correlations. ACTA ACUST UNITED AC 2016; 3:65-88. [PMID: 14247270 DOI: 10.1177/028418516500300111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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10
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Abstract
The core myopathies, Central Core Disease and Multiminicore Disease, are heterogeneous congenital myopathies with the common defining histopathological feature of focally reduced oxidative enzyme activity (central cores, multiminicores). Mutations in the gene encoding for the skeletal muscle ryanodine (RyR1) receptor are the most common cause. Mutations in the selenoprotein N (SEPN1) gene cause a less common variant. Pathogenic mechanisms underlying dominant RYR1 mutations have been extensively characterized, whereas those associated with recessive RYR1 and SEPN1 mutations are emerging. Identifying a specific genetic defect from the histopathological diagnosis of a core myopathy is complex and ought to be informed by a combined appraisal of histopathological, clinical, and, increasingly, muscle magnetic resonance imaging data. The present review aims at giving an overview of the main genetic and clinicopathological findings, with a major emphasis on features likely to inform the diagnostic process, as well as current treatments and perspectives for future research.
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Affiliation(s)
- Heinz Jungbluth
- Clinical Neuroscience Division, Institute of Psychiatry, King's College London, London, UK.
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Voermans NC, Bonnemann CG, Hamel BCJ, Jungbluth H, van Engelen BG. Joint hypermobility as a distinctive feature in the differential diagnosis of myopathies. J Neurol 2009; 256:13-27. [PMID: 19221853 DOI: 10.1007/s00415-009-0105-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Accepted: 09/08/2008] [Indexed: 02/07/2023]
Abstract
Congenital and adult-onset inherited myopathies represent a wide spectrum of syndromes. Classification is based upon clinical features and biochemical and genetic defects. Joint hypermobility is one of the distinctive clinical features that has often been underrecognized so far. We therefore present an overview of myopathies associated with joint hypermobility: Ullrich congenital muscular dystrophy, Bethlem myopathy, congenital muscular dystrophy with joint hyperlaxity, multi-minicore disease, central core disease, and limb girdle muscular dystrophy 2E with joint hyperlaxity and contractures. We shortly discuss a second group of disorders characterised by both muscular features and joint hypermobility: the inherited disorders of connective tissue Ehlers-Danlos syndrome and Marfan syndrome. Furthermore, we will briefly discuss the extent and pattern of joint hypermobility in these myopathies and connective tissue disorders and propose two grading scales commonly used to score the severity of joint hypermobility. We will conclude focusing on the various molecules involved in these disorders and on their role and interactions in muscle and tendon, with a view to further elucidate the pathophysiology of combined hypermobility and myopathy. Hopefully, this review will contribute to enhanced recognition of joint hypermobility and thus be of aid in differential diagnosis.
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Affiliation(s)
- N C Voermans
- Neuromuscular Centre Nijmegen, Dept. of Neurology, 935, Radboud University Nijmegen Medical Centre, 9101, 6500 HB Nijmegen, The Netherlands.
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Shirabe T. Muscle biopsy of a 15‐year‐old boy with muscle atrophy and weakness of the extremities from infancy. Neuropathology 2008. [DOI: 10.1111/j.1440-1789.2001.00371.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Teruo Shirabe
- Division of Neuropathology, Kawasaki Medical School, Kurashiki, Japan
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Abstract
Central core disease (CCD) is an inherited neuromuscular disorder characterised by central cores on muscle biopsy and clinical features of a congenital myopathy. Prevalence is unknown but the condition is probably more common than other congenital myopathies. CCD typically presents in infancy with hypotonia and motor developmental delay and is characterized by predominantly proximal weakness pronounced in the hip girdle; orthopaedic complications are common and malignant hyperthermia susceptibility (MHS) is a frequent complication. CCD and MHS are allelic conditions both due to (predominantly dominant) mutations in the skeletal muscle ryanodine receptor (RYR1) gene, encoding the principal skeletal muscle sarcoplasmic reticulum calcium release channel (RyR1). Altered excitability and/or changes in calcium homeostasis within muscle cells due to mutation-induced conformational changes of the RyR protein are considered the main pathogenetic mechanism(s). The diagnosis of CCD is based on the presence of suggestive clinical features and central cores on muscle biopsy; muscle MRI may show a characteristic pattern of selective muscle involvement and aid the diagnosis in cases with equivocal histopathological findings. Mutational analysis of the RYR1 gene may provide genetic confirmation of the diagnosis. Management is mainly supportive and has to anticipate susceptibility to potentially life-threatening reactions to general anaesthesia. Further evaluation of the underlying molecular mechanisms may provide the basis for future rational pharmacological treatment. In the majority of patients, weakness is static or only slowly progressive, with a favourable long-term outcome.
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Affiliation(s)
- Heinz Jungbluth
- Evelina Children's Hospital, Department of Paediatric Neurology, St. Thomas' Hospital, London, UK.
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14
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Ducreux S, Zorzato F, Ferreiro A, Jungbluth H, Muntoni F, Monnier N, Müller CR, Treves S. Functional properties of ryanodine receptors carrying three amino acid substitutions identified in patients affected by multi-minicore disease and central core disease, expressed in immortalized lymphocytes. Biochem J 2006; 395:259-66. [PMID: 16372898 PMCID: PMC1422771 DOI: 10.1042/bj20051282] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
More than 80 mutations in the skeletal muscle ryanodine receptor gene have been found to be associated with autosomal dominant forms of malignant hyperthermia and central core disease, and with recessive forms of multi-minicore disease. Studies on the functional effects of pathogenic dominant mutations have shown that they mostly affect intracellular Ca2+ homoeostasis, either by rendering the channel hypersensitive to activation (malignant hyperthermia) or by altering the amount of Ca2+ released subsequent to physiological or pharmacological activation (central core disease). In the present paper, we show, for the first time, data on the functional effect of two recently identified recessive ryanodine receptor 1 amino acid substitutions, P3527S and V4849I, as well as that of R999H, another substitution that was identified in two siblings that were affected by multi-minicore disease. We studied the intracellular Ca2+ homoeostasis of EBV (Epstein-Barr virus)-transformed lymphoblastoid cells from the affected patients, their healthy relatives and control individuals. Our results show that the P3527S substitution in the homozygous state affected the amount of Ca2+ released after pharmacological activation with 4-chloro-m-cresol and caffeine, but did not affect the size of the thapsigargin-sensitive Ca2+ stores. The other substitutions had no effect on either the size of the intracellular Ca2+ stores, or on the amount of Ca2+ released after ryanodine receptor activation; however, both the P3527S and V4849I substitutions had a small but significant effect on the resting Ca2+ concentration.
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Affiliation(s)
- Sylvie Ducreux
- Department of Anaesthesia and Research, Basel University Hospital, 4031 Basel, Switzerland
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Hellmann M, von Kleist-Retzow JC, Haupt WF, Herkenrath P, Schauseil-Zipf U. Diagnostic Value of Electromyography in Children and Adolescents. J Clin Neurophysiol 2005; 22:43-8. [PMID: 15689712 DOI: 10.1097/01.wnp.0000151146.91147.a1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The diagnostic accuracy in pediatric neurology has been considerably improved by new methods such as magnetic resonance imaging and molecular genetic analysis. However, standard diagnostic techniques continue to play an important role. The authors analyzed the diagnostic value of electromyography (EMG) and nerve conduction studies (NCS) in a retrospective study of 498 pediatric patients. The overall consistency between EMG results and the final clinical diagnosis in all children examined was 98%. In myogenic diseases, the concordance between EMG and clinical findings was lower (80%), because some patients with congenital myopathies showed normal EMG findings in this group. Peripheral neurogenic diseases were in all but one of the cases diagnosed correctly (99.5%). No decrease in diagnostic reliability was found in the younger age group. EMG and NCS examinations have to be adapted to the needs of children by an experienced examiner, but continue to be valuable diagnostic methods in pediatric neurology.
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Ducreux S, Zorzato F, Müller C, Sewry C, Muntoni F, Quinlivan R, Restagno G, Girard T, Treves S. Effect of Ryanodine Receptor Mutations on Interleukin-6 Release and Intracellular Calcium Homeostasis in Human Myotubes from Malignant Hyperthermia-susceptible Individuals and Patients Affected by Central Core Disease. J Biol Chem 2004; 279:43838-46. [PMID: 15299003 DOI: 10.1074/jbc.m403612200] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In this study we report for the first time the functional properties of human myotubes isolated from patients harboring the native RYR1 I4898T and R4893W mutations linked to central core disease. We examined two aspects of myotube physiology, namely excitation-contraction and excitation-secretion coupling. Our results show that upon activation of the ryanodine receptor (RYR), myotubes release interleukin-6 (IL-6); this was dependent on de novo protein synthesis and could be blocked by dantrolene and cyclosporine. Myotubes from the two patients affected by central core disease showed a 4-fold increase in the release of the inflammatory cytokine IL-6, compared with cells derived from control or malignant hyperthermia susceptible individuals. All tested myotubes released calcium from intracellular stores upon stimulation via surface membrane depolarization or direct RYR activation by 4-chloro-m-cresol. The functional impact on calcium release of RYR1 mutations linked to central core disease or malignant hyperthermia is different: human myotubes carrying the malignant hyperthermia-linked RYR1 mutation V2168M had a shift in their sensitivity to the RYR agonist 4-chloro-m-cresol to lower concentrations, whereas human myotubes harboring C-terminal mutations linked to central core disease exhibited reduced [Ca2+]i increase in response to 4-chloro-m-cresol, caffeine, and KCl. Taken together, these results suggest that abnormal release of calcium via mutated RYR enhances the production of the inflammatory cytokine IL-6, which may in turn affect signaling pathways responsible for the trophic status of muscle fibers.
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Affiliation(s)
- Sylvie Ducreux
- Department of Anaesthesia, Kantonsspital Basel, 4031, Switzerland
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17
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Alsaadi TM, Bateman LM, Laxer KD, Barbaro NM, Austin EJ, Garcia PA. Potentially misleading extratemporal lobe lesions in patients with temporal lobe epilepsy. J Neurol Neurosurg Psychiatry 2003; 74:566-9. [PMID: 12700292 PMCID: PMC1738424 DOI: 10.1136/jnnp.74.5.566] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
From a series of 217 consecutive temporal resections for intractable epilepsy between 1993 and 2000, we identified all patients with large non-neoplastic extratemporal lesions. Only patients with known postsurgical outcomes with follow up for more than two years were included. Fifteen patients were identified. All patients had a history of medically refractory epilepsy with clinical and ictal evidence of mesial temporal seizure onset. Eleven patients had extratemporal lesions ipsilateral to the seizure focus, whereas four patients had the lesions contralateral to the seizure focus. Nine of the 15 patients had evidence of hippocampal atrophy on magnetic resonance imaging (MRI). Following temporal resection, nine of these patients (60%) became seizure free (Engel class 1A), two patients were free of disabling seizures only (Engel class 1B), and two patients had a few early seizures but then became seizure free for at least two years (Engel class 1C). Two patients had significant improvement (Engel class 2). Thus, the finding of large extratemporal lesions on MRI was potentially misleading. When clinical semiology and ictal EEG recordings provide evidence of temporal onset seizures, anterior temporal resection should be considered in patients with extratemporal lesions.
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Affiliation(s)
- T M Alsaadi
- Department of Neurology, University of California, Davis, Sacramento 95817, USA.
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18
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Shirabe T. Muscle biopsy of a 15-year-old boy with muscle atrophy and weakness of the extremities from infancy. Neuropathology 2001; 21:95-6, 98. [PMID: 11304048 DOI: 10.1046/j.1440-1789.2001.00371.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- T Shirabe
- Division of Neuropathology, Kawasaki Medical School, Kurashiki, Japan
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19
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Miller S, Shevell M, Silver K, Kramer M. The diagnostic yield of the nerve-muscle skin biopsy in paediatric neurology practice. The Montreal Children's Hospital Neuromuscular Group. PEDIATRIC REHABILITATION 1998; 2:95-100. [PMID: 9744028 DOI: 10.3109/17518429809068161] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE To determine the diagnostic yield of the nerve-muscle-skin (NMS) biopsy in paediatric neurology practice. STUDY DESIGN A consecutive series of 98 paediatric NMS biopsies done 1989-1994 retrospectively reviewed in the context of pre-biopsy clinical and laboratory parameters. Bivariate associations based on chi-square test. Unconfounded associations between pre-biopsy variables and positive diagnostic yield (PDY) assessed by multiple logistic regression. RESULTS Fifty seven out of 98 patients central (global delay, seizures, abnormal CNS imaging) process; 41/98 patients peripheral (motor delay, weakness) process, electromyography-nerve conduction studies (EMG-NCS) 87/98 cases; abnormal 43/87. Positive diagnostic yield (PDY) in 42/98 (43%) biopsies. Statistically significant bivariate associations between PDY and pre-biopsy; age, presenting symptom, developmental delay, weakness, reflexes, CPK, lactate, EMG-NCS and process. Unconfounded associations demonstrated with PDY and age, reflexes and process. The presence of a peripheral process or an abnormal EMG-NCS strongly predictive of PDY: 34/41 (83%) peripheral process cases had PDY, 32/40 (80%) abnormal EMG-NCS cases had PDY, and 29/31 (93.5%) peripheral process and abnormal EMG-NCS cases had PDY. Abnormal EMG-NCS with central process improved PDY to 3/9 (33%) from 4/37 (11%) for normal EMG-NCS. CONCLUSION NMS biopsy is a valuable diagnostic tool, particularly in the context of a suspected peripheral process or a central processes with an abnormal EMG-NCS.
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Affiliation(s)
- S Miller
- Department of Neurology, McGill University, Montreal, Quebec, Canada
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20
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Abstract
Several dozen congenital myopathies are defined by clinical and morphological criteria. The application of the current generation of scientific techniques including immunohistochemistry and molecular genetics has resulted in the expansion of our knowledge and understanding of the well-established conditions including central core myopathy and centronuclear/myotubular myopathy and allowed greater understanding of the interrelationships of some of the less common or less well-established conditions. In the near future molecular genetics may allow the identification of the specific gene defect in many of these diseases. This article reviews the major congenital myopathies and presents some of the information gained by application of new technology to these conditions.
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Affiliation(s)
- J B Bodensteiner
- Department of Neurology, West Virginia University Health Science Center, Morgantown 26506-9180
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21
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Russell JW, Afifi AK, Ross MA. Predictive value of electromyography in diagnosis and prognosis of the hypotonic infant. J Child Neurol 1992; 7:387-91. [PMID: 1469246 DOI: 10.1177/088307389200700410] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To investigate the diagnostic validity of electromyography in the hypotonic infant, 79 children aged 0 to 12 months, seen over a 20-year period, were studied retrospectively. The diagnoses using clinical, muscle biopsy, and laboratory characteristics were: 25 central hypotonia, 20 spinal muscular atrophy, 20 myopathy, four myotonic dystrophy, four benign congenital hypotonia, two congenital muscular dystrophy, two myasthenia gravis, one infantile inflammatory myopathy, and one arthrogryposis multiplex congenita. Using strict criteria, electromyography accurately predicted the final diagnosis in 65% of infants with spinal muscular atrophy and was consistent with the diagnosis in another 25%. In contrast, electromyography accurately predicted the final diagnosis in only 10% of infants with myopathy and was normal in 88% of infants with central hypotonia. In infants with spinal muscular atrophy, there was no difference in the predictive value of electromyography when performed in the newborn compared to older infants. Normal distal nerve conduction velocities in infants with spinal muscular atrophy may predict prognosis, since these infants had a longer survival. Electromyography thus has a high predictive value for infantile spinal muscular atrophy but not for myopathy.
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Affiliation(s)
- J W Russell
- Department of Neurology, Faculty of Medicine, University of Iowa, Iowa City
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22
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Kausch K, Lehmann-Horn F, Janka M, Wieringa B, Grimm T, Müller CR. Evidence for linkage of the central core disease locus to the proximal long arm of human chromosome 19. Genomics 1991; 10:765-9. [PMID: 1889818 DOI: 10.1016/0888-7543(91)90461-m] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Central core disease of muscle (CCD; MIM 117000) is a rare inheritable myopathy that is frequently found in association with susceptibility to malignant hyperthermia (MHS). This observation has prompted us to perform a linkage study in CCD families using various chromosome 19q probes that are linked to the MHS locus and map close to the ryanodine receptor gene (RYR1), a strong MHS candidate gene. Our genetic linkage data support a location of the CCD gene on proximal 19q13.1 and thus suggest that CCD and MHS may be allelic.
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Affiliation(s)
- K Kausch
- Department of Human Genetics, University of Würzburg, Federal Republic of Germany
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23
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Oliveira AS, Schmidt B, Ferreira Neto A, Kiyomoto BH, Gabbai AA, Lima JG. [Congenital muscular dystrophy: histochemical study of the skeletal muscle in 17 patients]. ARQUIVOS DE NEURO-PSIQUIATRIA 1991; 49:185-91. [PMID: 1810237 DOI: 10.1590/s0004-282x1991000200012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
A thorough histological description of 17 patients with congenital muscular dystrophy (CMD) is presented. The biopsies were performed in the left superficial deltoid muscle and processed with histochemical techniques. All samples showed connective tissue proliferation, changes in the internal architecture, necrosis, increase of adipose tissue, macrophagia, fiber regeneration and segmentation, central nuclei, and type I fiber predominance. The histological hallmarks of this entity are the marked endomysial connective tissue proliferation that frames one fiber from the other, and the important changes in the fiber's internal architecture. Those two abnormalities are extremely helpful to differentiate, on histological grounds, CMD from limb girdle muscular dystrophy and Duchenne/Becker muscular dystrophy. CMD presents a particular natural course and should be individualized apart from other muscular dystrophies.
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Affiliation(s)
- A S Oliveira
- Disciplina de Neurologia, Escola Paulista de Medicina, São Paulo, Brasil
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24
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Mahdi AH. Genetically determined neurodegenerative disorders: experiences in Saudi Arabia. ANNALS OF TROPICAL PAEDIATRICS 1991; 11:17-23. [PMID: 1714690 DOI: 10.1080/02724936.1991.11747473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
There is, to date, hardly any literature on genetic neurodegenerative disorders from developing countries. This paper reports a study of 98 Saudi children with genetic neurodegenerative disorders. The four most encountered diagnoses were: spinal muscular atrophy, storage (lysosomal) disorders, neurocutaneous syndromes and aminoacidopathies. Consanguinity has been noted in about 50% of the families. In view of the major advances made in recent years in the recognition and treatment of these disorders, the role of the physician is discussed.
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Affiliation(s)
- A H Mahdi
- Department of Paediatrics, College of Medicine, King Saud University, Riyadh, Saudi Arabia
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25
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26
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Abstract
Congenital muscular dystrophy (CMD) is a disorder which usually presents at birth with skeletal muscle dysfunction. Cases have been described with associated severe central nervous system (CNS) abnormalities, but usually the condition proceeds without CNS impairment, particularly in less severe cases. A 25-year-old patient is described with clinical and pathological features of CMD accompanied by cerebellar dysfunction, most likely the result of cerebellar atrophy. This patient is thought to have a benign variety of CMD with CNS involvement, and this report stresses the fact that CMD can be associated with minimal CNS abnormalities and have a benign course.
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Affiliation(s)
- W A Knubley
- Department of Neurology, University of Tennessee, Memphis
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27
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Akazawa S, Shimizu R, Kasuda H, Nakao S, Nakamigawa T. Malignant hyperthermia associated with atypical central core disease. J Anesth 1987; 1:105-8. [PMID: 15237315 DOI: 10.1007/s0054070010105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/1986] [Accepted: 11/28/1986] [Indexed: 10/26/2022]
Affiliation(s)
- S Akazawa
- Department of Anesthesioloy, Jichi Medical School, Tochigi-ken, Japan
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28
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Abstract
Congenital muscular dystrophy (muscular dystrophy presenting from birth) with a wide spectrum of clinical severity is reported in 24 patients. Progression of symptoms was evident, leading to significant motor handicap in all patients and death in eight cases. Muscle enzyme studies did not always correlate with the severity of the disease. In six cases, initial muscle biopsy showed only minimal, nonspecific abnormalities; however, characteristic dystrophic changes were evident on repeat biopsies. Histochemical and electron microscopic studies did not show consistent changes, except type I predominance in a few cases. Evidently the condition is rarely, if ever, benign and the clinical course cannot be predicted from the initial presentation or early pathologic findings. Clinical, laboratory and pathologic characteristics are outlined for the diagnosis of this disorder.
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29
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Frank JP, Harati Y, Butler IJ, Nelson TE, Scott CI. Central core disease and malignant hyperthermia syndrome. Ann Neurol 1980; 7:11-7. [PMID: 7362206 DOI: 10.1002/ana.410070105] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In a detailed investigation of a family with musculoskeletal abnormalities observed in four generations, the proband and his mother were found to have central cores and multicores on histochemical and electron microscopic studies of biopsied muscle. A male sibling experienced a malignant hyperthermic reaction during hand surgery, and although similar reactions had not been observed in other family members, unexplained ventricular dysrhythmias did occur in the proband during surgery. The proband and his mother were subsequently shown to be susceptible to malignant hyperthermia by abnormal in vitro muscle contractures in the presence of halothane or caffeine. Physicians and dentists caring for patients with central core disease should be aware of its possible association with malignant hyperthermia. Complete evaluation of patients with central core disease should include in vitro muscle contracture studies for malignant hyperthermia since many of patients require surgery for musculoskeletal defects.
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30
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Pongratz D, Heuser M, Koppenwallner C, Hübner G. [Central core disease with "structured cores" in type II-fibers (author's transl)]. KLINISCHE WOCHENSCHRIFT 1976; 54:117-22. [PMID: 1255999 DOI: 10.1007/bf01468788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Report on a sporadic case with congenital slowly progressive neuromuscular disease. Light microscopic, ultrastructural and histochemical changes of muscle biopsy reveal the characteristics of central core disease with "structured cores" in type II-fibers.
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31
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Schmitt HP, Volk B. The relationship between target, targetoid, and targetoid/core fibers in severe neurogenic muscular atrophy. J Neurol 1975; 210:167-81. [PMID: 51074 DOI: 10.1007/bf00316244] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the m. tibialis anterior of a 68-year-old man with rapidly developing denervation atrophy in the legs since 1/2 year prior to death from heart stroke, abundant unifocal concentric fiber changes, such as target, targetoid/core, and targetoid fibers could be observed. Besides, large vacuolized fibers with multiple changes resembling cytoplasmic bodies in the peripheral zone were present as well; they are interpreted as fibers with multicentric target or targetoid formations. The target fibers displayed a broad variation of their outer appearance suggesting a continuous transition to targetoid/core fibers (with a dense center) and targetoid fibers (with a central change to aquous sarcoplasm showing a paucity of fibrillar structures). Very few fibers with a central densification of fibrillar material with or without a thin intermediate zone were fairly akin to core fibers of central core disease; others were more alike the type of targetoid fibers, previously described in the literature, showing a dense target-like center; both were summarized under the term, inaugurated by Engel et al. (1966), "targetoid/core fibers". Simultaneous occurrence of the different kinds of concentric fiber changes suggested a strong relation between all of them in the sense of representing different developmental stages of the same pathogenetic process. Thus, the central core disease, for instance, might be a disorder with a generalization of concentric fiber changes having come to arrest in the earliest stage of development.
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32
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33
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Afifi A, Zellweger H, McCormick WF. Congenital muscular dystrophy: light and electron microscopic observations. J Neurol Neurosurg Psychiatry 1969; 32:273-80. [PMID: 5807869 PMCID: PMC496513 DOI: 10.1136/jnnp.32.4.273] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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34
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Dunn HG. The Prader-Labhart-Willi syndrome: review of the literature and report of nine cases. ACTA PAEDIATRICA SCANDINAVICA 1968:Suppl 186:1+. [PMID: 5728638 DOI: 10.1111/j.1651-2227.1968.tb06038.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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35
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Zellweger H, Afifi A, McCormick WF, Mergner W. Benign congenital muscular dystrophy: a special form of congenital hypotonia. Clin Pediatr (Phila) 1967; 6:655-63. [PMID: 6058423 DOI: 10.1177/000992286700601113] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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36
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37
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38
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39
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40
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Gubbay SS, Walton JN, Pearce GW. Clinical and pathological study of a case of congenital muscular dystrophy. Journal of Neurology, Neurosurgery and Psychiatry 1966. [DOI: 10.1136/jnnp.29.6.500] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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41
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42
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43
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Die Bedeutung der Muskelbiopsie für die Diagnose und Therapie chronischer neuromuskulärer Prozesse. J Neurol 1965. [DOI: 10.1007/bf00242696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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44
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45
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GORDON N. STATIONARY MYOPATHIES. Dev Med Child Neurol 1964; 6:304-5. [PMID: 14155195 DOI: 10.1111/j.1469-8749.1964.tb10796.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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46
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47
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48
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49
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SLY M, HORNER FA, BOYARSKY LL, PACKER JT. A hypotonic infant. Clin Pediatr (Phila) 1963; 2:127-31. [PMID: 13989294 DOI: 10.1177/000992286300200306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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50
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