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Skolka MP, Milone M, Litchy WJ, Laughlin RS, Rubin DI, Liewluck T. The utility of electrodiagnostic testing in unprovoked rhabdomyolysis in the era of next-generation sequencing. Muscle Nerve 2024. [PMID: 38533679 DOI: 10.1002/mus.28087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 03/03/2024] [Accepted: 03/10/2024] [Indexed: 03/28/2024]
Abstract
INTRODUCTION/AIMS Rhabdomyolysis is an etiologically heterogeneous, acute necrosis of myofibers characterized by transient marked creatine kinase (CK) elevation associated with myalgia, muscle edema, and/or weakness. The study aimed to determine the role of electrodiagnostic (EDX) testing relative to genetic testing and muscle biopsy in patients with unprovoked rhabdomyolysis in identifying an underlying myopathy. METHODS EDX database was reviewed to identify unprovoked rhabdomyolysis patients who underwent EDX testing between January 2012 and January 2022. Each patient's clinical profile, EDX findings, muscle pathology, laboratory, and genetic testing results were analyzed. RESULTS Of 66 patients identified, 32 had myopathic electromyography (EMG). Muscle biopsy and genetic testing were performed in 41 and 37 patients, respectively. A definitive diagnosis was achieved in 15 patients (11 myopathic EMG and 4 nonmyopathic EMG; p = .04) based on abnormal muscle biopsy (4/11 patients) or genetic testing (12/12 patients, encompassing 5 patients with normal muscle biopsy and 3 patients with nonmyopathic EMG). These included seven metabolic and eight nonmetabolic myopathies (five muscular dystrophies and three ryanodine receptor 1 [RYR1]-myopathies). Patients were more likely to have baseline weakness (p < .01), elevated baseline CK (p < .01), and nonmetabolic myopathies (p = .03) when myopathic EMG was identified. DISCUSSION Myopathic EMG occurred in approximately half of patients with unprovoked rhabdomyolysis, more likely in patients with weakness and elevated CK at baseline. Although patients with myopathic EMG were more likely to have nonmetabolic myopathies, nonmyopathic EMG did not exclude myopathy, and genetic testing was primarily helpful to identify an underlying myopathy. Genetic testing should likely be first-tier diagnostic testing following unprovoked rhabdomyolysis.
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Affiliation(s)
| | | | | | | | - Devon I Rubin
- Department of Neurology, Mayo Clinic, Jacksonville, Florida, USA
| | - Teerin Liewluck
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
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2
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Traverso M, Baratto S, Iacomino M, Di Duca M, Panicucci C, Casalini S, Grandis M, Falace A, Torella A, Picillo E, Onore ME, Politano L, Nigro V, Innes AM, Barresi R, Bruno C, Zara F, Fiorillo C, Scala M. DAG1 haploinsufficiency is associated with sporadic and familial isolated or pauci-symptomatic hyperCKemia. Eur J Hum Genet 2024; 32:342-349. [PMID: 38177406 PMCID: PMC10923780 DOI: 10.1038/s41431-023-01516-4] [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: 08/25/2023] [Revised: 10/31/2023] [Accepted: 11/27/2023] [Indexed: 01/06/2024] Open
Abstract
DAG1 encodes for dystroglycan, a key component of the dystrophin-glycoprotein complex (DGC) with a pivotal role in skeletal muscle function and maintenance. Biallelic loss-of-function DAG1 variants cause severe muscular dystrophy and muscle-eye-brain disease. A possible contribution of DAG1 deficiency to milder muscular phenotypes has been suggested. We investigated the genetic background of twelve subjects with persistent mild-to-severe hyperCKemia to dissect the role of DAG1 in this condition. Genetic testing was performed through exome sequencing (ES) or custom NGS panels including various genes involved in a spectrum of muscular disorders. Histopathological and Western blot analyses were performed on muscle biopsy samples obtained from three patients. We identified seven novel heterozygous truncating variants in DAG1 segregating with isolated or pauci-symptomatic hyperCKemia in all families. The variants were rare and predicted to lead to nonsense-mediated mRNA decay or the formation of a truncated transcript. In four cases, DAG1 variants were inherited from similarly affected parents. Histopathological analysis revealed a decreased expression of dystroglycan subunits and Western blot confirmed a significantly reduced expression of beta-dystroglycan in muscle samples. This study supports the pathogenic role of DAG1 haploinsufficiency in isolated or pauci-symptomatic hyperCKemia, with implications for clinical management and genetic counseling.
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Affiliation(s)
- Monica Traverso
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Serena Baratto
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Michele Iacomino
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Marco Di Duca
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Chiara Panicucci
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Sara Casalini
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | | | - Antonio Falace
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Annalaura Torella
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Esther Picillo
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Maria Elena Onore
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Luisa Politano
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Vincenzo Nigro
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - A Micheil Innes
- Department of Medical Genetics and Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | | | - Claudio Bruno
- Centre of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Federico Zara
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
| | - Chiara Fiorillo
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
- Child Neuropsychiatry Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
| | - Marcello Scala
- Medical Genetics Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
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Fortunato F, Tonelli L, Farnè M, Selvatici R, Ferlini A. DMD deletions underlining mild dystrophinopathies: literature review highlights phenotype-related mutation clusters and provides insights about genetic mechanisms and prognosis. Front Neurol 2024; 14:1288721. [PMID: 38288333 PMCID: PMC10823016 DOI: 10.3389/fneur.2023.1288721] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 11/27/2023] [Indexed: 01/31/2024] Open
Abstract
DMD gene pathogenic variations cause a spectrum of phenotypes, ranging from severe Duchenne muscular dystrophy, the Becker milder cases, the intermediate or very mild muscle phenotypes invariably characterized by high CK, and the ultrarare fully-asymptomatic cases. Besides these phenotypes, X-linked dilated cardiomyopathy is also caused by DMD mutations. Males carrying DMD deletions with absent or very mild phenotypes have been sparsely described. We performed a horizon scan on public datasets to enroll males with the above phenotypes and carrying DMD deletions to delineate myopathic genotype-phenotype relationships. We inventoried 81 males, who were divided into the following clinical categorization: fully-asymptomatic males aged >43 years (A, N = 22); isolated hyperCKemia (CK, N = 35); and mild weakness (any age) with or without high CK (WCK, N = 24). In all cases, deleted intervals were exons 2 to 55, and no downstream exons were ever involved, apart from an exon 78 deletion in a WCK patient. All deletions were in-frame apart from the known exception to the rule of exon 2 and exon 78. We correlated the mild phenotypes (A and CK) to deleted exons, intronic breakpoints, exon-exon junctions, 3' isoforms rule, and protein epitopes, and we found that some genetic profiles are exclusively/mainly occurring in A/CK phenotypes, suggesting they are compatible with a quasi-normal muscular performance. We discussed diverse pathogenic mechanisms that may contribute to mild dystrophinopathic phenotypes, and we tried to address some "critical" genetic configurations or exon content needed to preserve a semi-functional DMD gene.
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Affiliation(s)
| | | | | | | | - Alessandra Ferlini
- Unit of Medical Genetics, Department of Medical Sciences, University of Ferrara, Ferrara, Italy
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4
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Massucco S, Gemelli C, Bellone E, Geroldi A, Patrone S, Mandich P, Scarsi E, Faedo E, Marinelli L, Mongini T, Traverso M, Baratto S, Schenone A, Fiorillo C, Grandis M. Skeletal muscle involvement in biallelic SORD mutations: case report and review of the literature. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2023; 42:113-117. [PMID: 38406380 PMCID: PMC10883325 DOI: 10.36185/2532-1900-323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/26/2023] [Indexed: 02/27/2024]
Abstract
Biallelic mutations in the sorbitol dehydrogenase (SORD) gene have been identified as a genetic cause of autosomal recessive axonal Charcot-Marie-Tooth disease 2 (CMT2) and distal hereditary motor neuropathy (dHMN). We herein review the main phenotypes associated with SORD mutations and report the case of a 16-year-old man who was referred to our outpatient clinic for a slowly worsening gait disorder with wasting and weakness of distal lower limbs musculature. Since creatine phosphokinase (CPK) values were persistently raised (1.5fold increased) and a Next-Generation Sequencing CMT-associated panel failed in identifying pathogenic variants, a muscle biopsy was performed with evidence of alterations suggestive of a protein surplus distal myopathy. Finally, Whole-Exome Sequencing (WES) identified two pathogenic SORD variants in the heterozygous state: c.458C > A (p.Ala153Asp) and c.757delG (p.Ala253Glnfs*27). This is an isolated report of compound heterozygosity for two SORD mutations associated with clinical and histological signs of skeletal muscle involvement, expanding the phenotypic expression of SORD mutations.
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Affiliation(s)
- Sara Massucco
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
| | | | - Emilia Bellone
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Alessandro Geroldi
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
| | - Serena Patrone
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
| | - Paola Mandich
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Elena Scarsi
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
| | - Elena Faedo
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
| | - Lucio Marinelli
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Tiziana Mongini
- Neuromuscular Unit, Department of Neurosciences, University of Turin, Turin, Italy
| | - Monica Traverso
- Laboratory of Neurogenetics, Department of Neuroscience, IRCCS Institute G. Gaslini, Genoa, Italy
| | - Serena Baratto
- Unit of Myology, IRCCS Institute G. Gaslini, Genoa, Italy
| | - Angelo Schenone
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Chiara Fiorillo
- Child Neuropsychiatry Unit, University of Genoa and IRCCS Institute G. Gaslini, Genoa, Italy
| | - Marina Grandis
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetic and Maternal and Infantile Sciences (DINOGMI), University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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5
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Gaudio A, Gotta F, Ponti C, Sanguineri F, Trevisan L, Geroldi A, Patrone S, Gemelli C, Cabona C, Astrea G, Fiorillo C, Gustincich S, Grandis M, Mandich P. Case report: Episodic ataxia without ataxia? Front Neurol 2023; 14:1224241. [PMID: 37965175 PMCID: PMC10640972 DOI: 10.3389/fneur.2023.1224241] [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: 05/17/2023] [Accepted: 10/03/2023] [Indexed: 11/16/2023] Open
Abstract
Hereditary myopathies represent a clinically and genetically heterogeneous group of neuromuscular disorders, characterized by highly variable clinical presentations and frequently overlapping phenotypes with other neuromuscular disorders, likely influenced by genetic and environmental modifiers. Genetic testing is often challenging due to ambiguous clinical diagnosis. Here, we present the case of a family with clinical and Electromyography (EMG) features resembling a myotonia-like disorder in which Whole Exome Sequencing (WES) analysis revealed the co-segregation of two rare missense variants in UBR4 and HSPG2, genes previously associated with episodic ataxia 8 (EA8). A review of the literature highlighted a striking overlap between the clinical and the molecular features of our family and the previously described episodic ataxias (EAs), which raises concerns about the genotype-phenotype correlation, clinical variability, and the confounding overlap in these groups of disorders. This emphasizes the importance of thoroughly framing the patient's phenotype. The more clear-cut the diagnosis, the easier the identification of a genetic determinant, and the better the prognosis and the treatment of patients.
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Affiliation(s)
- Andrea Gaudio
- IRCCS Ospedale Policlinico San Martino—UOC Genetica Medica, Genova, Italy
| | - Fabio Gotta
- IRCCS Ospedale Policlinico San Martino—UOC Genetica Medica, Genova, Italy
| | - Clarissa Ponti
- IRCCS Ospedale Policlinico San Martino—UOC Genetica Medica, Genova, Italy
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
| | - Francesca Sanguineri
- IRCCS Ospedale Policlinico San Martino—UOC Genetica Medica, Genova, Italy
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
| | - Lucia Trevisan
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
- IRCCS Ospedale Policlinico San Martino—SS Centro Tumori Ereditari, Genova, Italy
| | - Alessandro Geroldi
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
| | - Serena Patrone
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
| | - Chiara Gemelli
- IRCCS-Ospedale Policlinico San Martino—UOC Clinica Neurologica, Genova, Italy
| | - Corrado Cabona
- IRCCS-Ospedale Policlinico San Martino—UOC Neurofisiopatologia, Genova, Italy
| | | | - Chiara Fiorillo
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
- IRCCS Istituto Giannina Gaslini—UOC Neuropsichiatria Infantile, Genova, Italy
| | - Stefano Gustincich
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, Genova, Italy
| | - Marina Grandis
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
- IRCCS-Ospedale Policlinico San Martino—UOC Clinica Neurologica, Genova, Italy
| | - Paola Mandich
- IRCCS Ospedale Policlinico San Martino—UOC Genetica Medica, Genova, Italy
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genova, Genova, Italy
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6
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Fu X, Yang X, Wang X, Jia B, Ma W, Xiong H, Fang F, Ren X, Lv J. HyperCKemia: An early sign of childhood-onset neutral lipid storage disease with myopathy. Neuromuscul Disord 2023; 33:81-89. [PMID: 37620213 DOI: 10.1016/j.nmd.2023.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 07/12/2023] [Accepted: 07/24/2023] [Indexed: 08/26/2023]
Abstract
Neutral lipid-storage disease with myopathy (NLSDM) is an autosomal recessive neuromuscular disorder caused by mutations in PNPLA2, and the average age at onset is 30 years. To date, only eight patients with childhood-onset NLSDM have been reported in detail. We investigated 3 unreported patients with NLSDM detected in childhood and reviewed 8 childhood-onset and 82 adult-onset patients with NLSDM documented in the literature. In the childhood-onset cohort, NLSDM presented initially as asymptomatic or paucisymptomatic hyperCKemia in 6/11 patients, and follow-up data showed onset of muscle weakness in 6/11 childhood-onset patients. In the adult-onset cohort, 95.1% (78/82) of patients showed muscle weakness. Cardiac involvement developed in 6/11 childhood-onset patients. Hepatomegaly was observed in 3/11 childhood-onset patients. Serum creatine kinase levels were elevated greater than five-fold of the upper limit of normal (ULN) in most childhood-onset patients and were elevated to less than ten-fold of the ULN in most adult-onset patients. Peripheral blood smears and muscle biopsies showed cytoplasmic lipid droplets in leukocytes and myocytes. NLSDM can present in children with asymptomatic or paucisymptomatic hyperCKemia before the onset of muscle weakness. The presence of lipid droplets in leucocytes (Jordans' anomaly) aids in diagnosing and confirming the pathogenicity of PNPLA2 variants of uncertain significance. There were no clear genotype-phenotype correlations in patients with NLSDM.
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Affiliation(s)
- Xiaona Fu
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Xinying Yang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Xiaofei Wang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Bingbing Jia
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Wenna Ma
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Fang Fang
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China
| | - Xiaotun Ren
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China.
| | - Junlan Lv
- Department of Neurology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing 100045, China.
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7
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Invernizzi F, Izzo R, Colangelo I, Legati A, Zanetti N, Garavaglia B, Lamantea E, Peverelli L, Ardissone A, Moroni I, Maggi L, Bonanno S, Fiori L, Velardo D, Magri F, Comi GP, Ronchi D, Ghezzi D, Lamperti C. NGS-Based Genetic Analysis in a Cohort of Italian Patients with Suspected Inherited Myopathies and/or HyperCKemia. Genes (Basel) 2023; 14:1393. [PMID: 37510298 PMCID: PMC10379733 DOI: 10.3390/genes14071393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 06/26/2023] [Accepted: 06/28/2023] [Indexed: 07/30/2023] Open
Abstract
Introduction/Aims HyperCKemia is considered a hallmark of neuromuscular diseases. It can be either isolated or associated with cramps, myalgia, weakness, myoglobinuria, or rhabdomyolysis, suggesting a metabolic myopathy. The aim of this work was to investigate possible genetic causes in order to help diagnose patients with recurrent hyperCKemia or clinical suspicion of inherited metabolic myopathy. Methods A cohort of 139 patients (90 adults and 49 children) was analyzed using a custom panel containing 54 genes associated with hyperCKemia. Results A definite genetic diagnosis was obtained in 15.1% of cases, while candidate variants or variants of uncertain significance were found in a further 39.5%. Similar percentages were obtained in patients with infantile or adult onset, with some different causative genes. RYR1 was the gene most frequently identified, either with single or compound heterozygous variants, while ETFDH variants were the most common cause for recessive cases. In one patient, mRNA analysis allowed identifying a large LPIN1 deletion missed by DNA sequencing, leading to a certain diagnosis. Conclusion These data confirm the high genetic heterogeneity of hyperCKemia and metabolic myopathies. The reduced diagnostic yield suggests the existence of additional genes associated with this condition but also allows speculation that a significant number of cases presenting with hyperCKemia or muscle symptoms are due to extrinsic, not genetic, factors.
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Affiliation(s)
- Federica Invernizzi
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Rossella Izzo
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Isabel Colangelo
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Andrea Legati
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Nadia Zanetti
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Barbara Garavaglia
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Eleonora Lamantea
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Lorenzo Peverelli
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
| | - Anna Ardissone
- Child Neurology Unit-Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Isabella Moroni
- Child Neurology Unit-Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Lorenzo Maggi
- Department of Neuroimmunology and Neuromuscular Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Silvia Bonanno
- Department of Neuroimmunology and Neuromuscular Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Laura Fiori
- UOS di Malattie Metaboliche e Nutrizione, Ospedale dei Bambini Vittore Buzzi, 20154 Milan, Italy
| | - Daniele Velardo
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Francesca Magri
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Giacomo P Comi
- Neuromuscular and Rare Disease Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Pathophysiology and Transplantation, Dino Ferrari Center, University of Milan, 20122 Milan, Italy
| | - Dario Ronchi
- Neurology Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
- Department of Pathophysiology and Transplantation, Dino Ferrari Center, University of Milan, 20122 Milan, Italy
| | - Daniele Ghezzi
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
- Lab of Neurogenetics and Mitochondrial Disorders, Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy
| | - Costanza Lamperti
- Medical Genetics and Neurogenetics Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20126 Milan, Italy
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8
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Urtizberea JA, Severa G, Malfatti E. Metabolic Myopathies in the Era of Next-Generation Sequencing. Genes (Basel) 2023; 14:genes14050954. [PMID: 37239314 DOI: 10.3390/genes14050954] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/07/2023] [Accepted: 04/18/2023] [Indexed: 05/28/2023] Open
Abstract
Metabolic myopathies are rare inherited disorders that deserve more attention from neurologists and pediatricians. Pompe disease and McArdle disease represent some of the most common diseases in clinical practice; however, other less common diseases are now better-known. In general the pathophysiology of metabolic myopathies needs to be better understood. Thanks to the advent of next-generation sequencing (NGS), genetic testing has replaced more invasive investigations and sophisticated enzymatic assays to reach a final diagnosis in many cases. The current diagnostic algorithms for metabolic myopathies have integrated this paradigm shift and restrict invasive investigations for complicated cases. Moreover, NGS contributes to the discovery of novel genes and proteins, providing new insights into muscle metabolism and pathophysiology. More importantly, a growing number of these conditions are amenable to therapeutic approaches such as diets of different kinds, exercise training protocols, and enzyme replacement therapy or gene therapy. Prevention and management-notably of rhabdomyolysis-are key to avoiding serious and potentially life-threatening complications and improving patients' quality of life. Although not devoid of limitations, the newborn screening programs that are currently mushrooming across the globe show that early intervention in metabolic myopathies is a key factor for better therapeutic efficacy and long-term prognosis. As a whole NGS has largely increased the diagnostic yield of metabolic myopathies, but more invasive but classical investigations are still critical when the genetic diagnosis is unclear or when it comes to optimizing the follow-up and care of these muscular disorders.
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Affiliation(s)
| | - Gianmarco Severa
- Department of Medical, Surgical and Neurological Sciences, Neurology-Neurophysiology Unit, University of Siena, Policlinico Le Scotte, Viale Bracci 1, 5310 Siena, Italy
- Université Paris Est, U955, IMRB, INSERM, APHP, Centre de Référence de Pathologie Neuromusculaire Nord-Est-Ile-de-France, Henri Mondor Hospital, 94000 Créteil, France
| | - Edoardo Malfatti
- Université Paris Est, U955, IMRB, INSERM, APHP, Centre de Référence de Pathologie Neuromusculaire Nord-Est-Ile-de-France, Henri Mondor Hospital, 94000 Créteil, France
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Pasca D, Ginsberg M. Causes of HyperCKemia in Children: A Retrospective Cohort Study. J Child Neurol 2022; 38:25-30. [PMID: 36567615 DOI: 10.1177/08830738221147808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Background and Objectives: Creatine kinase (CK) is a commonly used screening test for neuromuscular disorders (NMDs). However, hyperCKemia can result from several pathologic and physiologic causes. We analyzed neuromuscular disorders in noninfant children with hyperCKemia including those with no weakness and mild CK elevations (<5 times the upper limit of normal). We hypothesized that children with mild CK elevation and no weakness would be unlikely to have neuromuscular disorders and require additional evaluation. Methods: We retrospectively evaluated patients between 1 and 18 years of age seen at a single children's hospital over a 3-calendar-year period with initial total CK values greater than the upper limit of normal with at least 2 years of follow-up data. Final diagnoses were analyzed and associations with possible risk factors assessed. Receiver operating characteristic curves were generated to assess altering CK cutoff values. Results: Of 260 subjects with hyperCKemia, 18 had a neuromuscular disorder (6.9%, 95% confidence interval [CI] 4.2%-10.9%). Of 166 subjects with CK <5 times the upper limit of normal and no weakness, 8 had a neuromuscular disorder (4.8%, 95% CI 2.3%-9.6%). Weakness (odds ratio [OR] 32.5, 95% CI 4-385, P = .0002), and family history of neuromuscular disorders (OR not calculable, P = .0003) were associated with neuromuscular disorders. An optimal CK threshold of 777 was identified on receiver operating characteristic curve analysis (sensitivity of 72% and specificity of 64%). The most commonly identified neuromuscular disorders were muscular dystrophies, inflammatory myopathies, and metabolic myopathies. Conclusion: Most children with hyperCKemia will not be diagnosed with a neuromuscular disorder, but a significant minority even with mild hyperCKemia and without weakness may warrant additional evaluation.
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Affiliation(s)
- Damaris Pasca
- Division of Neurology, 1079Akron Children's Hospital, Akron, OH, USA
| | - Matthew Ginsberg
- Division of Neurology, 1079Akron Children's Hospital, Akron, OH, USA
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A genetic basis is identified in 74% cases of paediatric hyperCKaemia without weakness presenting to a tertiary paediatric neuromuscular centre. Neuromuscul Disord 2022; 32:707-717. [DOI: 10.1016/j.nmd.2022.07.401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 06/23/2022] [Accepted: 07/25/2022] [Indexed: 11/20/2022]
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