1
|
Ramdas S, Painho T, Vanegas MI, Famili DT, Lim MJ, Jungbluth H. Targeted Treatments for Myasthenia Gravis in Children and Adolescents. Paediatr Drugs 2024:10.1007/s40272-024-00649-3. [PMID: 39198371 DOI: 10.1007/s40272-024-00649-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/04/2024] [Indexed: 09/01/2024]
Abstract
Myasthenia gravis (MG) is an antibody-mediated disorder of the neuromuscular junction affecting children and adults. MG is a treatable condition with most patients requiring immunosuppression for disease control and/or remission. Juvenile myasthenia gravis (JMG) is rare in comparison with adult-onset MG but given the same underlying pathophysiology, treatment strategies are similar to those in adults. Until recently, there were only a few randomised controlled trials (RCTs) for MG treatments in adults and none in children, and management strategies were primarily based on expert consensus. In addition, treatment options for refractory MG cases have been severely limited, resulting in poor long-term quality of life in such patients due to the significant disease burden. Recently, there have been several RCTs focussing on novel therapeutic strategies with potentially promising outcomes, suggesting a change in MG management over the coming years and access to more effective and faster-acting drugs for MG patients. This paper will review current and new MG treatments including efgartigimod, eculizumab, rozanolixizumab, ravulizumab, and zilucoplan, with a focus on juvenile myasthenia gravis.
Collapse
Affiliation(s)
- Sithara Ramdas
- Department of Paediatrics, MDUK Neuromuscular Centre, University of Oxford, Oxford, UK
- Department of Paediatric Neurology, John Radcliffe Hospital, Oxford, UK
| | - Teresa Painho
- Department of Paediatrics, MDUK Neuromuscular Centre, University of Oxford, Oxford, UK
- Neurology Unit, Hospital Dona Estefânia, Unidade Local de Saúde São José, Centro Clínico Académico de Lisboa, Lisbon, Portugal
| | - Maria I Vanegas
- Department of Paediatric Neurology, Evelina London Children's Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, Children's Neurosciences Centre, F02-Becket House, Lambeth Palace Road, London, SE1 7EU, UK
| | - Dennis T Famili
- Department of Paediatric Neurology, Evelina London Children's Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, Children's Neurosciences Centre, F02-Becket House, Lambeth Palace Road, London, SE1 7EU, UK
| | - Ming J Lim
- Department of Paediatric Neurology, Evelina London Children's Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, Children's Neurosciences Centre, F02-Becket House, Lambeth Palace Road, London, SE1 7EU, UK
- Women and Children's Health, Faculty of Life Sciences and Medicine (FoLSM), King's College London, London, UK
| | - Heinz Jungbluth
- Department of Paediatric Neurology, Evelina London Children's Hospital, Guy's & St. Thomas' Hospital NHS Foundation Trust, Children's Neurosciences Centre, F02-Becket House, Lambeth Palace Road, London, SE1 7EU, UK.
- Randall Centre for Cell and Molecular Biophysics, Muscle Signalling Section, Faculty of Life Sciences and Medicine (FoLSM), King's College London, London, UK.
| |
Collapse
|
2
|
Brandsema JF, Ginsberg M, Hoshino H, Mimaki M, Nagata S, Rao VK, Ruzhansky K, Suresh N, Tiongson E, Yamanouchi H, Frick G, Hicks E, Liao S, Howard JF. Eculizumab in Adolescent Patients With Refractory Generalized Myasthenia Gravis: A Phase 3, Open-Label, Multicenter Study. Pediatr Neurol 2024; 156:198-207. [PMID: 38810600 DOI: 10.1016/j.pediatrneurol.2024.04.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 03/10/2024] [Accepted: 04/21/2024] [Indexed: 05/31/2024]
Abstract
BACKGROUND This study evaluated the efficacy and safety of eculizumab, a terminal complement C5 inhibitor, in juvenile generalized myasthenia gravis (gMG). METHODS Adolescents aged 12 to 17 years with refractory anti-acetylcholine receptor (AChR) antibody-positive gMG received eculizumab (weekly induction [one to two doses of 600 mg or four doses of 900 mg] followed by maintenance doses [300 to 1200 mg] every two weeks for up to 26 weeks) in a phase 3, open-label multicenter study (NCT03759366). Change from baseline to week 26 in Quantitative Myasthenia Gravis (QMG) total score (primary end point) and secondary end points including Myasthenia Gravis-Activities of Daily Living (MG-ADL) total score, Myasthenia Gravis Composite score, Myasthenia Gravis Foundation of America postintervention status, EuroQol 5-Dimensions (Youth) and Neurological Quality-of-Life Pediatric Fatigue questionnaire scores, as well as pharmacokinetics, pharmacodynamics, and safety, were recorded. RESULTS Eleven adolescents (mean ± S.D. age 14.8 ± 1.8 years) were enrolled; 10 completed the primary evaluation period. Least-squares mean changes from baseline at week 26 were -5.8 (standard error [SE] 1.2; P = 0.0004) for QMG total score and -2.3 (SE 0.6; P = 0.0017) for MG-ADL total score. Overall, the primary and all secondary efficacy end point analyses met statistical significance from the first assessment and were sustained throughout. Complete terminal complement inhibition was sustained through 26 weeks in all patients. Treatment-emergent adverse events were all mild/moderate and predominantly unrelated to eculizumab. CONCLUSIONS Eculizumab was effective in reducing disease burden and was well tolerated in adolescents with refractory AChR antibody-positive gMG.
Collapse
Affiliation(s)
- John F Brandsema
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | | | - Hideki Hoshino
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
| | - Masakazu Mimaki
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
| | - Satoru Nagata
- Department of Pediatrics, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
| | - Vamshi K Rao
- Division of Neurology, Lurie Children's Hospital, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Katherine Ruzhansky
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina
| | - Niraja Suresh
- Department of Neurology, University of South Florida, Tampa, Florida
| | - Emmanuelle Tiongson
- Division of Neurology, Children's Hospital Los Angeles, Los Angeles, California
| | - Hideo Yamanouchi
- Department of Pediatrics, Comprehensive Epilepsy Center, Saitama Medical University, Saitama, Japan
| | - Glen Frick
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts.
| | - Eden Hicks
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts
| | - Serena Liao
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts
| | - James F Howard
- Department of Neurology, The University of North Carolina, Chapel Hill, North Carolina
| |
Collapse
|
3
|
Antonioni A, Raho EM, Carlucci D, Sette E, De Gennaro R, Capone JG, Govoni V, Casetta I, Pugliatti M, Granieri E. The Incidence of Myasthenia Gravis in the Province of Ferrara, Italy, in the Period of 2008-2022: An Update on a 40-Year Observation and the Influence of the COVID-19 Pandemic. J Clin Med 2023; 13:236. [PMID: 38202243 PMCID: PMC10780173 DOI: 10.3390/jcm13010236] [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: 12/06/2023] [Revised: 12/23/2023] [Accepted: 12/29/2023] [Indexed: 01/12/2024] Open
Abstract
Myasthenia gravis (MG) is the most common neuromuscular junction disorder. We evaluated the MG incidence rate in the province of Ferrara, Northern Italy, over two time frames (2008-2018 and 2019-2022, i.e., the COVID-19 pandemic) and considered early-onset (EOMG), late-onset (LOMG), and thymoma- and non-thymoma-associated MG. Moreover, in the second period, we assessed its possible relationship with SARS-CoV-2 infection or COVID-19 vaccination. We used a complete enumeration approach to estimate the MG incidence and its temporal trend. For the period of 2008-18, 106 new cases were identified (mean incidence rate 2.7/100,000 people). The highest rates were observed for the over-70 age group and in rural areas, with 17% of thymoma-associated MG. During the COVID-19 period, 29 new cases were identified (average incidence rate 2.1/100,000 people), showing a marked (though not statistically significant) decrease in the mean annual incidence compared to the previous period. Again, the highest rate was observed for the over-70 age group. The first period was in line with our previous observations for the period between 1985 and 2007, highlighting a rising incidence of LOMG and a marked decrease in EOMG. During the COVID-19 period, incidence rates were lower in the first years whereas, when the pandemic ended, the previous trend was confirmed.
Collapse
Affiliation(s)
- Annibale Antonioni
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
- Doctoral Program in Translational Neurosciences and Neurotechnologies, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy
| | - Emanuela Maria Raho
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| | - Domenico Carlucci
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| | - Elisabetta Sette
- Unit of Neurology, Interdistrict Health Care Department of Neurosciences, S. Anna Ferrara University Hospital, 44124 Ferrara, Italy
| | - Riccardo De Gennaro
- Unit of Neurology, Interdistrict Health Care Department of Neurosciences, S. Anna Ferrara University Hospital, 44124 Ferrara, Italy
| | - Jay Guido Capone
- Unit of Neurology, Interdistrict Health Care Department of Neurosciences, S. Anna Ferrara University Hospital, 44124 Ferrara, Italy
| | - Vittorio Govoni
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| | - Ilaria Casetta
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| | - Maura Pugliatti
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| | - Enrico Granieri
- Unit of Neurology, Department of Neurosciences and Rehabilitation, University of Ferrara, 44121 Ferrara, Italy; (A.A.); (E.M.R.); (I.C.); (M.P.)
| |
Collapse
|
4
|
Özsoy Ö, Cinleti T, Günay Ç, Sarıkaya Uzan G, Giray Bozkaya Ö, Çağlayan AO, Hız Kurul S, Yiş U. Genetic, serological and clinical evaluation of childhood myasthenia syndromes- single center subgroup analysis experience in Turkey. Acta Neurol Belg 2023; 123:2325-2335. [PMID: 37656362 DOI: 10.1007/s13760-023-02370-3] [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: 04/04/2023] [Accepted: 08/21/2023] [Indexed: 09/02/2023]
Abstract
BACKGROUND Congenital myasthenic syndrome is a disease that occurs due to several types such as mutations in different pre-synaptic, synaptic, post-synaptic proteins and, glycosylation defects associated with congenital myopathy. Juvenile myasthenia gravis is an autoimmune condition usually caused by antibodies targeting the acetylcholine receptor. AIMS Our objective is to conduct an analysis on the subgroup traits exhibited by patients who have been diagnosed with congenital myasthenic syndrome and juvenile myasthenia gravis, with a focus on their long-term monitoring and management. METHODS This study was conducted on children diagnosed with myasthenia gravis, who were under the care of Dokuz Eylul University's Department of Pediatric Neurology for a period of ten years. RESULTS A total of 22 (12 congenital myasthenic syndrome, 10 juvenile myasthenia gravis) patients were identified. Defects in the acetylcholine receptor (6/12) were the most common type in the congenital myasthenic syndrome group. Basal-lamina-related defects (5/12) were the second most prevalent. One patient had a GFPT1 gene mutation (1/12). Patients with ocular myasthenia gravis (n = 6) exhibited milder symptoms. In the generalized myasthenia gravis group (n = 4), specifically in postpubertal girls, a more severe clinical progression was observed, leading to the implementation of more aggressive treatment strategies. CONCLUSION This study highlights that clinical recognition of congenital myasthenic syndrome and knowledge of related genes will aid the rapid diagnosis and treatment of these rare neuromuscular disorders. Findings in the juvenile myasthenia gravis group demonstrate the impact of pubertal development and the need for timely and appropriate active therapy, including thymectomy, to improve prognosis.
Collapse
Affiliation(s)
- Özlem Özsoy
- Department of Pediatric Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey.
| | - Tayfun Cinleti
- Department of Pediatric Genetics, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Çağatay Günay
- Department of Pediatric Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Gamze Sarıkaya Uzan
- Department of Pediatric Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Özlem Giray Bozkaya
- Department of Pediatric Genetics, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| | - Ahmet Okay Çağlayan
- Department of Medical Genetics, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
- Department of Molecular Medicine, Institute of Health Sciences, Dokuz Eylül University, İzmir, Turkey
| | - Semra Hız Kurul
- Department of Pediatric Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
- İzmir Biomedicine and Genome Center, Dokuz Eylül University Health Campus, İzmir, Turkey
- İzmir International Biomedicine and Genome Institute, Dokuz Eylül University, İzmir, Turkey
| | - Uluç Yiş
- Department of Pediatric Neurology, Faculty of Medicine, Dokuz Eylül University, İzmir, Turkey
| |
Collapse
|
5
|
Huang EJC, Wu MH, Wang TJ, Huang TJ, Li YR, Lee CY. Myasthenia Gravis: Novel Findings and Perspectives on Traditional to Regenerative Therapeutic Interventions. Aging Dis 2023; 14:1070-1092. [PMID: 37163445 PMCID: PMC10389825 DOI: 10.14336/ad.2022.1215] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 12/15/2022] [Indexed: 05/12/2023] Open
Abstract
The prevalence of myasthenia gravis (MG), an autoimmune disorder, is increasing among all subsets of the population leading to an elevated economic and social burden. The pathogenesis of MG is characterized by the synthesis of autoantibodies against the acetylcholine receptor (AChR), low-density lipoprotein receptor-related protein 4 (LRP4), or muscle-specific kinase at the neuromuscular junction, thereby leading to muscular weakness and fatigue. Based on clinical and laboratory examinations, the research is focused on distinguishing MG from other autoimmune, genetic diseases of neuromuscular transmission. Technological advancements in machine learning, a subset of artificial intelligence (AI) have been assistive in accurate diagnosis and management. Besides, addressing the clinical needs of MG patients is critical to improving quality of life (QoL) and satisfaction. Lifestyle changes including physical exercise and traditional Chinese medicine/herbs have also been shown to exert an ameliorative impact on MG progression. To achieve enhanced therapeutic efficacy, cholinesterase inhibitors, immunosuppressive drugs, and steroids in addition to plasma exchange therapy are widely recommended. Under surgical intervention, thymectomy is the only feasible alternative to removing thymoma to overcome thymoma-associated MG. Although these conventional and current therapeutic approaches are effective, the associated adverse events and surgical complexity limit their wide application. Moreover, Restivo et al. also, to increase survival and QoL, further recent developments revealed that antibody, gene, and regenerative therapies (such as stem cells and exosomes) are currently being investigated as a safer and more efficacious alternative. Considering these above-mentioned points, we have comprehensively reviewed the recent advances in pathological etiologies of MG including COVID-19, and its therapeutic management.
Collapse
Affiliation(s)
- Evelyn Jou-Chen Huang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Meng-Huang Wu
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Wang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Huang
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Yan-Rong Li
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Linkou Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
| | - Ching-Yu Lee
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
- International PhD Program for Cell Therapy and Regeneration Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.
| |
Collapse
|
6
|
Morar R, Seedat F, Richards GA. Clinical features and outcomes of patients with myasthenia gravis admitted to an intensive care unit: A 20-year retrospective study. SOUTHERN AFRICAN JOURNAL OF CRITICAL CARE 2023; 39:10.7196/SAJCC.2023.v39i2.561. [PMID: 37547769 PMCID: PMC10399547 DOI: 10.7196/sajcc.2023.v39i2.561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 05/28/2023] [Indexed: 08/08/2023] Open
Abstract
Background There are limited data on the clinical characteristics and outcomes of patients with myasthenia gravis (MG) admitted to the intensive care unit (ICU) at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH). Objectives The aim was to study the clinical characteristics and outcomes of patients with MG admitted to the CMJAH over two decades. Methods A retrospective study was undertaken of patients with MG admitted to the multidisciplinary ICU of CMJAH over a 20-year period, from 1998 to 2017. Demographic data, clinical features, management and outcomes of patients were assessed and reviewed from the case records. Results Thirty-four patients with MG were admitted to the ICU during this period: 24 female and 10 male. The mean age ± SD was 37.4 ± 13.0 years, with a range of 16 - 66 years. Four patients were human immunodeficiency virus (HIV)-positive. The mean length of stay (LOS) in ICU was 10.6 ± 20.1 days, ranging from 1 to 115 days. Two patients were diagnosed with MG in the ICU after failure to wean from the ventilator. Overall, 22 patients were intubated and ventilated on admission. Morbidities included self-extubation, aspiration pneumonia and iatrogenic pneumothorax. History of thymectomy was present in 12 patients. The treatments received for MG included pyridostigmine (73.5%), corticosteroids (55.9%), azathioprine (35.3%), plasmapheresis (26.5%) and intravenous immunoglobulin (8.8%). The overall mortality in the ICU was 5.9%. Conclusion MG is a serious disorder with considerable morbidity and mortality. It is, however, a potentially manageable disease, provided that appropriate ICU resources are available. Contributions of the study This study provides further insight into the characteristics and outcomes of myasthenia gravis patients in ICU, within a South African context.
Collapse
Affiliation(s)
- R Morar
- School of Clinical Medicine, Faculty of Health Sciences; Division of Pulmonology and Critical Care, Department of Internal Medicine, Charlotte
Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - GEMP 2 Group 6 of 2018 (M Amod, F Chappel, L Ebbeling, L Fikizolo, A Glover, K Gutu,
C Lawson, R Maswinyaneng, M Mohunlal, K Morar, D Rooken-Smith, K Seale, D Shai)
- GEMP 2 Group 6 of 2018, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - F Seedat
- School of Clinical Medicine, Faculty of Health Sciences; Division of Pulmonology and Critical Care, Department of Internal Medicine, Charlotte
Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - G A Richards
- School of Clinical Medicine, Faculty of Health Sciences; Division of Pulmonology and Critical Care, Department of Internal Medicine, Charlotte
Maxeke Johannesburg Academic Hospital, University of the Witwatersrand, Johannesburg, South Africa
| |
Collapse
|
7
|
Tang YL, Ruan Z, Su Y, Guo RJ, Gao T, Liu Y, Li HH, Sun C, Li ZY, Chang T. Clinical Characteristics and Prognosis of Very late-onset Myasthenia Gravis in China. Neuromuscul Disord 2023; 33:358-366. [PMID: 36990040 DOI: 10.1016/j.nmd.2023.02.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/26/2023] [Accepted: 02/28/2023] [Indexed: 03/07/2023]
Abstract
Alteration in onset-age distribution in myasthenia gravis (MG) and its increasing prevalence among the elderly underscores the need for a better understanding of the clinical course of MG and the establishment of personalized treatment. In this study we reviewed the demographics, clinical profile, and treatment of MG. Based on onset age, eligible patients were classified as early-onset MG (onset age ≥18 and <50 years), late-onset MG (onset age ≥50 and <65 years), and very late-onset MG (onset age ≥65 years). Overall, 1160 eligible patients were enrolled. Patients with late- and very late-onset MG showed a male predominance (P=0.02), ocular MG subtype (P=0.001), and seropositivity for acetylcholine receptors and titin antibodies (P<0.001). In very late-onset MG, a lower proportion of patients retained minimal manifestations status or better, a higher proportion of patients had MG-related deaths (P<0.001), and a shorter maintenance time of minimal manifestation status or better was seen at the last follow-up (P=0.007) than that in patients with early- and late-onset MG. Non-immunotherapy may associated with a poor prognosis in patients in the very late-onset group. Further studies on very late-onset MG patients should be performed to evaluate the relationship between immunotherapy and prognosis.
Collapse
Affiliation(s)
- Yong-Lan Tang
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Zhe Ruan
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China.
| | - Yue Su
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Rong-Jing Guo
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Ting Gao
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Yu Liu
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Huan-Huan Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Chao Sun
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China
| | - Zhu-Yi Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China.
| | - Ting Chang
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an 710038, China.
| |
Collapse
|
8
|
Ndondo AP, Eley B, Wilmshurst JM, Kakooza-Mwesige A, Giannoccaro MP, Willison HJ, Cruz PMR, Heckmann JM, Bateman K, Vincent A. Post-Infectious Autoimmunity in the Central (CNS) and Peripheral (PNS) Nervous Systems: An African Perspective. Front Immunol 2022; 13:833548. [PMID: 35356001 PMCID: PMC8959857 DOI: 10.3389/fimmu.2022.833548] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Accepted: 02/10/2022] [Indexed: 11/13/2022] Open
Abstract
The direct impact and sequelae of infections in children and adults result in significant morbidity and mortality especially when they involve the central (CNS) or peripheral nervous system (PNS). The historical understanding of the pathophysiology has been mostly focused on the direct impact of the various pathogens through neural tissue invasion. However, with the better understanding of neuroimmunology, there is a rapidly growing realization of the contribution of the innate and adaptive host immune responses in the pathogenesis of many CNS and PNS diseases. The balance between the protective and pathologic sequelae of immunity is fragile and can easily be tipped towards harm for the host. The matter of immune privilege and surveillance of the CNS/PNS compartments and the role of the blood-brain barrier (BBB) and blood nerve barrier (BNB) makes this even more complex. Our understanding of the pathogenesis of many post-infectious manifestations of various microbial agents remains elusive, especially in the diverse African setting. Our exploration and better understanding of the neuroimmunology of some of the infectious diseases that we encounter in the continent will go a long way into helping us to improve their management and therefore lessen the burden. Africa is diverse and uniquely poised because of the mix of the classic, well described, autoimmune disease entities and the specifically "tropical" conditions. This review explores the current understanding of some of the para- and post-infectious autoimmune manifestations of CNS and PNS diseases in the African context. We highlight the clinical presentations, diagnosis and treatment of these neurological disorders and underscore the knowledge gaps and perspectives for future research using disease models of conditions that we see in the continent, some of which are not uniquely African and, where relevant, include discussion of the proposed mechanisms underlying pathogen-induced autoimmunity. This review covers the following conditions as models and highlight those in which a relationship with COVID-19 infection has been reported: a) Acute Necrotizing Encephalopathy; b) Measles-associated encephalopathies; c) Human Immunodeficiency Virus (HIV) neuroimmune disorders, and particularly the difficulties associated with classical post-infectious autoimmune disorders such as the Guillain-Barré syndrome in the context of HIV and other infections. Finally, we describe NMDA-R encephalitis, which can be post-HSV encephalitis, summarise other antibody-mediated CNS diseases and describe myasthenia gravis as the classic antibody-mediated disease but with special features in Africa.
Collapse
Affiliation(s)
- Alvin Pumelele Ndondo
- Department of Paediatric Neurology, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Brian Eley
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa.,Paediatric Infectious Diseases Unit, Red Cross War Memorial Children's Hospital, Cape Town, South Africa
| | - Jo Madeleine Wilmshurst
- Department of Paediatrics and Child Health, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa.,Department of Paediatric Neurology, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Angelina Kakooza-Mwesige
- Department of Pediatrics and Child Health, School of Medicine, Makerere University College of Health Sciences, Kampala, Uganda
| | - Maria Pia Giannoccaro
- Laboratory of Neuromuscular Pathology and Neuroimmunology, Istituto di Ricovero e Cura a CarattereScientifico (IRCCS) Instiuto delle Scienze Neurologiche di Bologna, UOC Clinica Neurologica Bologna, Bologna, Italy.,Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Hugh J Willison
- Institute of Infection, Immunity and Inflammation (3I), University of Glasgow, Glasgow, United Kingdom
| | - Pedro M Rodríguez Cruz
- Centro Nacional de Analisis Genomico - Centre for Genomic Regulation (CNAG-CRG ), Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Department of Neuromuscular Disease, University College London (UCL) Queen Square Institute of Neurology, London, United Kingdom.,Faculté de Médecine, de Pharmacie et d'Odontologie, Université Cheikh Anta Diop, Dakar, Senegal
| | - Jeannine M Heckmann
- Neurology Division, Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa.,The University of Cape Town (UCT) Neurosciences Institute, University of Cape Town, Cape Town, South Africa
| | - Kathleen Bateman
- Neurology Division, Department of Medicine, Groote Schuur Hospital, Cape Town, South Africa
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
9
|
Europa TA, Nel M, Lebeko MR, Heckmann JM. Mitochondrial bioenergetics in ocular fibroblasts of two myasthenia gravis cases. IBRO Neurosci Rep 2022; 12:297-302. [PMID: 35746973 PMCID: PMC9210483 DOI: 10.1016/j.ibneur.2022.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 04/19/2022] [Indexed: 11/28/2022] Open
Abstract
Myasthenia gravis (MG) is a rare, treatable, antibody-mediated disease characterized by fatigable muscle weakness of extraocular muscles (EOMs) and non-ocular skeletal muscles. The antibodies are directed against muscle-endplate proteins, most frequently the acetylcholine receptor (AChR) alpha-subunit. Although most MG patients respond to immunosuppressive treatment, some individuals, frequently with African-genetic ancestry, develop treatment-resistant ophthalmoplegia (OP-MG). Although the underlying pathogenetic mechanisms of OP-MG remain unknown, experimental rodent models of MG showed upregulation of genes involved in oxidative metabolism in muscles. EOMs are highly dependent on oxidative metabolism. We opportunistically sampled EOM-tendons of two rare OP-MG patients (and non-MG controls) undergoing re-alignment surgery, and established ocular fibroblast cultures. Metabolic assays were performed on these live cells to assess real-time differences in energy metabolism. To study the cellular bioenergetic profiles in the context of MG, we exposed the cultures to homologous 5% MG sera for 24 h, vs. growth media, from two independent MG patients (with circulating AChR-antibodies) and five controls without MG, and estimated the fold change in oxygen consumption rates in response to three compounds which inhibit different mitochondrial chain complexes. Quantitative PCR (qPCR) was performed in cells before and after MG sera exposure, to assess transcript levels of mitochondrial genes, PDK4, ANGPTL4 and UCP3, which were altered in experimental MG. In response to the mitochondrial stressors, basal oxidative metabolism parameters were similar between OP-MG and control fibroblasts (p = 0.81). However, after exposure to MG sera, bioenergetic parameters (oxygen consumption rate as an indicator of oxidative phosphorylation; extracellular acidification rate as an indicator of glycolysis), were induced to higher levels in OP-MG fibroblasts compared to controls (2.6-fold vs 1.5-fold; p = 0.031) without evidence of mitochondrial insufficiency in the OP-MG ocular fibroblasts. In support of the bioenergetic responses to the same MG sera, gene transcripts of PDK4 and ANGPLT4 in ocular fibroblasts also showed significant upregulation (p ≤ 0.041), but similarly in OP-MG and control cases. Taken together we showed similar basal and metabolic adaptive responses after exposure to mitochondrial inhibitors in ocular fibroblasts derived from OP-MG cases and controls, although the OP-MG cells showed greater activation in response to MG conditions. These pilot results in orbital-derived tissues provide support for myasthenic-induced changes in cellular metabolism and evidence that orbital fibroblasts may be useful for dynamic bioenergetic assessments. Orbital fibroblasts may be useful for dynamic bioenergetic assays. Orbital-fibroblast cultures showed shifts in oxidative metabolism induced by homologous myasthenic sera. Altered bioenergetic adaptation was induced by MG sera in orbital fibroblasts from ophthalmoplegic MG patients compared to controls.
Collapse
Affiliation(s)
- Tarin A. Europa
- Neurology Research Group, UCT Neurosciences Institute, University of Cape Town, Cape Town, South Africa
| | - Melissa Nel
- Neurology Research Group, UCT Neurosciences Institute, University of Cape Town, Cape Town, South Africa
- Neurology Division, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Maribanyana R. Lebeko
- Hair and Skin Research Laboratory, Division of Dermatology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Jeannine M. Heckmann
- Neurology Research Group, UCT Neurosciences Institute, University of Cape Town, Cape Town, South Africa
- Neurology Division, Department of Medicine, University of Cape Town, Cape Town, South Africa
- Correspondence to: Neurology E-8-74, Groote Schuur Hospital, Observatory, 7925 Cape Town, South Africa.
| |
Collapse
|
10
|
Heckmann JM, Europa TA, Soni AJ, Nel M. The Epidemiology and Phenotypes of Ocular Manifestations in Childhood and Juvenile Myasthenia Gravis: A Review. Front Neurol 2022; 13:834212. [PMID: 35280301 PMCID: PMC8904732 DOI: 10.3389/fneur.2022.834212] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 01/24/2022] [Indexed: 11/28/2022] Open
Abstract
Myasthenia gravis (MG) appears to have a similar incidence among adult populations worldwide. However, epidemiological and phenotypic differences have been noted among children and juveniles with MG. We reviewed the literature on childhood- and juvenile-onset MG among different populations, with the focus on ocular involvement, antibody profiles, the genetic susceptibility to juvenile MG phenotypes, the use of immune treatments, and the reported responses of extraocular muscles to therapies. Although epidemiological studies used different methodologies, reports from Asia, compared to Europe, showed more than two-fold higher proportions of prepubertal onset (before 12 years) vs. postpubertal-onset juveniles with MG. Compared to European children, ocular MG was 4-fold more frequent among Asian children, and 2–3-fold more frequent among children with African ancestry both in prepubertal and postpubertal ages at onset. These results suggest genetic influences. In Asia, HLA-B*46 and DRB1*09 appeared overrepresented in children with ocular MG. In Europe, children with MG had a significantly higher rate of transforming from ocular to generalized disease and with an overrepresentation of HLADRB1*04. Although treatment regimens vary widely and the responses to immune therapies of the ocular muscles involved in MG were generally poorly described, there were indications that earlier use of steroid therapy may have better outcomes. Reports of treatment-resistant ophthalmoplegia may be more frequent in African and Asian juvenile MG cohorts compared to Europeans. Genetic and muscle gene expression studies point to dysregulated muscle atrophy signaling and mitochondrial metabolism pathways as pathogenetic mechanisms underpinning treatment-resistant ophthalmoplegia in susceptible individuals. In conclusion, phenotypic differences in juveniles with ocular manifestations of MG were evident in different populations suggesting pathogenetic influences. Treatment responses in MG-associated ocular disease should attract more careful descriptive reports. In MG, extraocular muscles may be vulnerable to critical periods of poor force generation and certain individuals may be particularly susceptible to developing treatment-resistant ophthalmoplegia. The development of prognostic biomarkers to identify these susceptible individuals is an unmet need.
Collapse
Affiliation(s)
- Jeannine M Heckmann
- Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa.,Neurology Research Group, University of Cape Town (UCT) Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Tarin A Europa
- Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa.,Neurology Research Group, University of Cape Town (UCT) Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Aayesha J Soni
- Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Melissa Nel
- Neurology Research Group, University of Cape Town (UCT) Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
11
|
Punga AR, Maddison P, Heckmann JM, Guptill JT, Evoli A. Epidemiology, diagnostics, and biomarkers of autoimmune neuromuscular junction disorders. Lancet Neurol 2022; 21:176-188. [DOI: 10.1016/s1474-4422(21)00297-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/18/2021] [Accepted: 08/25/2021] [Indexed: 12/14/2022]
|
12
|
Albassam MS, Thabet SA, Hmoud M, Makkawi S. Anti-Muscle Specific Kinase (Anti-MuSK) Positive Myasthenia Gravis Overlapping With Parkinson's Disease: A Challenging Diagnosis. Cureus 2021; 13:e14839. [PMID: 34104586 PMCID: PMC8174120 DOI: 10.7759/cureus.14839] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The concomitance between Parkinson's disease (PD) and myasthenia gravis (MG) is rare, with only a few case reports in the literature and only one of them with positive anti-muscle specific kinase (anti-MuSK) MG. The overlap between PD and MG symptoms can cause a diagnostic dilemma for the treating physician. In this report, we present a 73-year-old lady with a history of recurrent falls, dysphagia, and diplopia. She was found to have ptosis, vertical gaze restriction, neck extension, and flexion weakness, as well as features of parkinsonism, including masked face appearance, asymmetrical limbs rigidity, and bradykinesia. She was found to have a high titer antibody for MuSK MG. Her MG symptoms were treated successfully with rituximab.
Collapse
Affiliation(s)
- Mohammed S Albassam
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, SAU
| | - Salman A Thabet
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, SAU
| | - Mohammed Hmoud
- Department of Medicine, Ministry of the National Guard-Health Affairs, Jeddah, SAU.,College of Medicine, University of Bisha, Bisha, SAU
| | - Seraj Makkawi
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Jeddah, SAU.,Research and Development, King Abdullah International Medical Research Center, Jeddah, SAU.,Department of Medicine, Ministry of the National Guard-Health Affairs, Jeddah, SAU
| |
Collapse
|
13
|
Bubuioc AM, Kudebayeva A, Turuspekova S, Lisnic V, Leone MA. The epidemiology of myasthenia gravis. J Med Life 2021; 14:7-16. [PMID: 33767779 PMCID: PMC7982252 DOI: 10.25122/jml-2020-0145] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/14/2020] [Indexed: 11/17/2022] Open
Abstract
Neuromuscular junction (NMJ) disorders include several dysfunctions that ultimately lead to muscle weakness. Myasthenia gravis (MG) is the most prevalent NMJ disorder with a highly polymorphic clinical presentation and many different faces. Being an autoimmune disease, MG correlates with the presence of detectable antibodies directed against the acetylcholine receptor, muscle-specific kinase, lipoprotein-related protein 4, agrin, titin, and ryanodine in the postsynaptic membrane at the NMJ. MG has become a prototype serving to understand both autoimmunity and the function of the NMJ better. The aim of this review is to synthesize some of the epidemiological data available. Epidemiological data regarding MG are important for postulating hypotheses regarding its etiology and facilitating the description of MG subtypes. Thus, adequate documentation through broad databases is essential. The incidence and prevalence of MG reported around the globe have been rising steadily and consistently over the past decades. Ethnic aspects, gender-related differences, and environmental risk factors have been described, implying that these might contribute to a specific phenotype, further suggesting that MG may be considered an umbrella term that covers several clinical entities.
Collapse
Affiliation(s)
- Ana-Maria Bubuioc
- Department of Neurology, Nicolae Testemitanu State University of Medicine and Pharmacy Chisinau, the Republic of Moldova
| | - Aigerim Kudebayeva
- Department of Neurology, Kazakh Medical University of Continuing Education, Almaty, Kazakhstan
| | - Saule Turuspekova
- Department of Nervous Diseases with course of Neurosurgery, Asfendiyarov Kazakh National Medical University, Almaty, Kazakhstan
| | - Vitalie Lisnic
- Department of Neurology, Nicolae Testemitanu State University of Medicine and Pharmacy Chisinau, the Republic of Moldova
| | - Maurizio Angelo Leone
- Neurology Unit, Fondazione IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo, Italy
| |
Collapse
|
14
|
Alzuabi MA, Manolopoulos A, Elmashala A, Odabashian R, Naddaf E, Murad MH. Immunoglobulin for myasthenia gravis. Hippokratia 2020. [DOI: 10.1002/14651858.cd013801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Muayad A Alzuabi
- Department of Neuroscience, Division of Clinical Neurology; Medical University of South Carolina; Charleston SC USA
| | - Apostolos Manolopoulos
- Clinical Research and Evidence-Based Medicine Unit, Second Medical Department; Aristotle University of Thessaloniki; Thessaloniki Greece
| | - Amjad Elmashala
- Department of Neurology; Iowa University Hospitals; Iowa City IA USA
| | - Roupen Odabashian
- Department of Internal Medicine; University of Toronto; Toronto Canada
| | - Elie Naddaf
- Department of Neurology; Mayo Clinic; Rochester MN USA
| | - M Hassan Murad
- Mayo Evidence-based Practice Center (EPC); Mayo Clinic; Rochester MN USA
| |
Collapse
|
15
|
Incidence, mortality, and economic burden of myasthenia gravis in China: A nationwide population-based study. LANCET REGIONAL HEALTH-WESTERN PACIFIC 2020; 5:100063. [PMID: 34327399 PMCID: PMC8315547 DOI: 10.1016/j.lanwpc.2020.100063] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 11/11/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023]
Abstract
Background Myasthenia gravis (MG) is the most common primary disorder of neuromuscular transmission, but the incidence of MG in China is unknown. We conducted the first nationwide study to determine the incidence and mortality rates of MG in all age groups at the national level in China. Methods This national population-based registry study is based on the database of the Hospital Quality Monitoring System of National Health Commission, which covers 1665 hospitals providing myasthenia gravis care in 31 provinces and municipalities across China. 94,638 hospital admissions for 59,243 myasthenia gravis patients were identified from January 1st, 2016 to December 31st, 2018. Myasthenia gravis was identified by ICD-10 codes (G70). Incidence of myasthenia gravis was stratified by age, sex, and province. Findings Of 59,243 patients, 30,503 individuals with myasthenia gravis were newly diagnosed. Age and sex adjusted incidence of myasthenia gravis was 0.68 per 100,000 person-years, with highest in the age group of 70–74 years. The incidence in females was 0.76 per 100,000 and 0.60 per 100,000 in males. The admission mortality rate was 14.69‰. Respiratory failure was the leading cause of death in patients with myasthenic crisis. There were 14,840 patients with thymomas, encompassing 14,636 (26.5%) adults and 204 (7.1%) juveniles. 9453 (63.7%) patients with thymomas underwent thymomectomy. The median length of hospital stay was 8 days (interquartile range (IQR) 4 to 15 days) with median hospitalization cost $1037 (IQR $493 to $2925). The Basic Medical Insurance was the most common payment method, covering 67.4% of patients. Interpretation The age and sex adjusted incidence of MG was 0.68 per 100,000 person-years in China. The admission mortality rate was 14.69‰. Most cases of new onset MG occurred in the seventh decade of life. Funding National Science Foundation of China (91642205, and 81830038); Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing
Collapse
|
16
|
Heckmann JM, Marais S. Management Issues in Myasthenia Gravis Patients Living With HIV: A Case Series and Literature Review. Front Neurol 2020; 11:775. [PMID: 32973647 PMCID: PMC7472955 DOI: 10.3389/fneur.2020.00775] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 06/24/2020] [Indexed: 12/19/2022] Open
Abstract
South Africa is home to more than seven million people living with human immunodeficiency virus (HIV) and a high prevalence of tuberculosis. Human immunodeficiency virus–infected individuals may develop myasthenia gravis (MG), which raises questions regarding their management. An MG database, with 24 years of observational data, was audited for HIV-infected persons. Case reports of MG in HIV-infected persons were reviewed. We identified 17 persons with MG and HIV infection. All had generalized MG with a mean age at onset of 37.8 years. Eleven had acetylcholine receptor antibody–positive MG; one had antibodies against muscle-specific kinase. Six developed MG prior to HIV infection (mean CD4+ 361 cells/mm3); four worsened <6 months of starting antiretrovirals. Eleven developed MG while HIV-infected (mean CD4+ 423 cells/mm3); five presented with mild MG; three in MG crisis requiring rescue therapies (intravenous immune globulin or plasma exchange and/or intravenous cyclophosphamide). Two were diagnosed with HIV infection and MG at the same time. Fifteen required maintenance steroid-sparing immune therapies, predominantly azathioprine, or methotrexate. Plasma HIV viral loads remained below detectable levels on antiretrovirals during immunosuppressant treatment. Over the average follow-up of 6 years, 10 achieved minimal manifestation status, and the remainder improved to mild symptoms. Three cases had tuberculosis before MG, but none developed tuberculosis reactivation on immunosuppressive therapy; one used isoniazid prophylaxis. Herpes zoster reactivation during treatment occurred in one. Conclusions include the following: MG in HIV-infected patients should be managed similarly to individuals without HIV infection; half develop moderate–severe MG; MG symptoms may worsen within 6 months of antiretroviral initiation; safety monitoring must include plasma HIV viral load estimation. Isoniazid prophylaxis may not be indicated in all cases.
Collapse
Affiliation(s)
- Jeannine M Heckmann
- Neurology, Department of Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa.,Neurology Research Group, UCT Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Suzaan Marais
- Neurology, Department of Medicine, Groote Schuur Hospital and University of Cape Town, Cape Town, South Africa.,Neurology Research Group, UCT Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
17
|
O'Connell K, Ramdas S, Palace J. Management of Juvenile Myasthenia Gravis. Front Neurol 2020; 11:743. [PMID: 32793107 PMCID: PMC7393473 DOI: 10.3389/fneur.2020.00743] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/16/2020] [Indexed: 02/06/2023] Open
Abstract
Juvenile Myasthenia Gravis (JMG) is a rare disorder, defined as myasthenia gravis in children younger than 18 years of age. While clinical phenotypes are similar to adults, there are a number of caveats that influence management: broader differential diagnoses; higher rates of spontaneous remission; and the need to initiate appropriate treatment early, to avoid the long-term physical and psychosocial morbidity. Current practice is taken from treatment guidelines for adult MG or individual experience, with considerable variability seen across centers. We discuss our approach to treating JMG, in a large specialist JMG service, and review currently available evidence and highlight potential areas for future research. First-line treatment of generalized JMG is symptomatic management with pyridostigmine, but early use of immunosuppression, where good control is not achieved is important. Oral prednisolone is used as first-line immunosuppression with appropriate prevention and monitoring of side effects. Second-line therapies including azathioprine and mycophenolate may be considered where there is: no response to steroids, inability to wean to a reasonable minimum effective dose or if side-effects are intolerable. Management of ocular JMG is similar, but requires close involvement of ophthalmology in young children to prevent amblyopia. Muscle-specific tyrosine kinase (MuSK)-JMG show a poorer response to pyridostigmine and anecdotal evidence suggests that rituximab should be considered as second-line immunosuppression. Thymectomy is indicated in any patient with a thymoma, and consideration should be given in acetylcholine receptor (AChR) positive JMG allowing time for spontaneous remission. The benefit is less clear in ocular JMG and is not advised in MuSK-JMG. Children experiencing a myasthenic crisis require urgent hospital admission with access to the intensive care unit. PLEX is preferred over IVIG due to rapid onset of action, but this needs to be balanced with feasibility in very young children. Key questions remain in the management of JMG: when to initiate both first- and second-line treatments, choosing between steroid-sparing agents, and determining the optimal dose and treatment duration. We feel that given the rarity of this disease, the establishment of national registries and collaboration across groups will be needed to address these issues and facilitate future drug trials in JMG.
Collapse
Affiliation(s)
- Karen O'Connell
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Sithara Ramdas
- Department of Paediatric Neurology, John Radcliffe Hospital, Oxford, United Kingdom
| | - Jacqueline Palace
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
18
|
Odajiu I, Davidescu EI, Mitu C, Popescu BO. Patients with Parkinson's Disease and Myasthenia Gravis-A Report of Three New Cases and Review of the Literature. ACTA ACUST UNITED AC 2019; 56:medicina56010005. [PMID: 31878081 PMCID: PMC7022960 DOI: 10.3390/medicina56010005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 12/13/2019] [Accepted: 12/20/2019] [Indexed: 12/15/2022]
Abstract
Neurodegenerative diseases such as Parkinson's disease (PD)have increasing incidence, due to lifespan expansion. The association between PD and Myasthenia Gravis (MG) is uncommon, and so far, since 1987, 26 cases have been reported. We report here a series of three new cases, two men and one woman with this peculiar combination of conditions, identified in the Neurology Department of Colentina Clinical Hospital. In this article, the pathogenesis of MG in patients with PD is discussed, along with a literature review regarding the co-occurrence of these two neurological diseases.
Collapse
Affiliation(s)
- Irina Odajiu
- Neurology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania; (I.O.); (C.M.); (B.O.P.)
| | - Eugenia Irene Davidescu
- Neurology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania; (I.O.); (C.M.); (B.O.P.)
- Department of Clinical Neurosciences, ‘Carol Davila’ University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Correspondence: ; Tel.: +40-722-258-350
| | - Cristina Mitu
- Neurology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania; (I.O.); (C.M.); (B.O.P.)
| | - Bogdan Ovidiu Popescu
- Neurology Department, Colentina Clinical Hospital, 020125 Bucharest, Romania; (I.O.); (C.M.); (B.O.P.)
- Department of Clinical Neurosciences, ‘Carol Davila’ University of Medicine and Pharmacy, 020021 Bucharest, Romania
- Laboratory of Molecular Biology, ‘Victor Babeș’ National Institute of Pathology, 050096 Bucharest, Romania
| |
Collapse
|
19
|
Abstract
BACKGROUND Neurological disorders in HIV infection are a common cause of morbidity and mortality. The aim of this paper is to provide a narrative overview of up to date information concerning neurological disorders affecting HIV infected persons in Africa. METHODS Seminal research concerning neurological disorders among HIV-infected adults in sub-Saharan Africa from prior to 2000 was combined with an in-depth search of PubMed to identify literature published from 2000 to 2017. The following Mesh terms were used. "Nervous System Diseases" "HIV Infections" and "Africa South of the Sahara" and "Seizures" or "Spinal Cord Diseases" or "Peripheral Nervous System Diseases" or "AIDS Dementia Complex" or "Opportunistic Infections" or "Immune Reconstitution Inflammatory Syndrome" or "Stroke". Only those articles written in English were used. A total of 352 articles were identified, selected and reviewed and 180 were included in the study. These included case series, observational studies, interventional studies, guidelines and reviews with metanalyses. The author also included 15 publications on the subject covering the earlier phase of the HIV epidemic in Africa from 1987 to 1999 making a total of 195 references in the study. This was combined with extensive personal experience diagnosing and treating these neurological disorders. RESULTS Neurological disorders were common, typically occurring in WHO stages III/IV. These were in three main categories: those arising from opportunistic processes mostly infections, direct HIV infection and autoimmunity. The most common were those arising from direct HIV infection occurring in >50%. These included HIV-associated neurocognitive dysfunction (HAND), neuropathy and myelopathy. Opportunistic infections occurred in >20% and frequently had a 6-9-month mortality rate of 60-70%. The main causes were cryptococcus, tuberculosis, toxoplasmosis and acute bacterial meningitis. Concurrent systemic tuberculosis occurred in almost 50%. CONCLUSION Neurological disorders are common in HIV in Africa and the main CNS opportunistic infections result in high mortality rates. Strategies aimed at reducing their high burden, morbidity and mortality include early HIV diagnosis and anti-retroviral therapy (ART), screening and chemoprophylaxis of main opportunistic infections, improved clinical diagnosis and management and programme strengthening.
Collapse
Affiliation(s)
- William P Howlett
- Department of Internal Medicine, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Center for International Health, University of Bergen, Norway
| |
Collapse
|
20
|
Nel M, Mulder N, Europa TA, Heckmann JM. Using Whole Genome Sequencing in an African Subphenotype of Myasthenia Gravis to Generate a Pathogenetic Hypothesis. Front Genet 2019; 10:136. [PMID: 30881381 PMCID: PMC6406016 DOI: 10.3389/fgene.2019.00136] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/11/2019] [Indexed: 12/25/2022] Open
Abstract
Myasthenia gravis (MG) is a rare, treatable antibody-mediated disease which is characterized by muscle weakness. The pathogenic antibodies are most frequently directed at the acetylcholine receptors (AChRs) at the skeletal muscle endplate. An ophthalmoplegic subphenotype of MG (OP-MG), which is characterized by treatment resistant weakness of the extraocular muscles (EOMs), occurs in a proportion of myasthenics with juvenile symptom onset and African genetic ancestry. Since the pathogenetic mechanism(s) underlying OP-MG is unknown, the aim of this study was to use a hypothesis-generating genome-wide analysis to identify candidate OP-MG susceptibility genes and pathways. Whole genome sequencing (WGS) was performed on 25 AChR-antibody positive myasthenic individuals of African genetic ancestry sampled from the phenotypic extremes: 15 with OP-MG and 10 individuals with control MG (EOM treatment-responsive). Variants were called according to the Genome Analysis Toolkit (GATK) best practice guidelines using the hg38 reference genome. In addition to single variant association analysis, variants were mapped to genes (±200 kb) using VEGAS2 to calculate gene-based test statistics and HLA allele group assignment was inferred through "best-match" alignment of reads against the IMGT/HLA database. While there were no single variant associations that reached genome-wide significance in this exploratory sample, several genes with significant gene-based test statistics and known to be expressed in skeletal muscle had biological functions which converge on muscle atrophy signaling and myosin II function. The closely linked HLA-DPA1 and HLA-DPB1 genes were associated with OP-MG subjects (gene-based p < 0.05) and the frequency of a functional A > G SNP (rs9277534) in the HLA-DPB1 3'UTR, which increases HLA-DPB1 expression, differed between the two groups (G-allele 0.30 in OP-MG vs. 0.60 in control MG; p = 0.04). Furthermore, we show that rs9277534 is an HLA-DBP1 expression quantitative trait locus in patient-derived myocytes (p < 1 × 10-3). The application of a SNP to gene to pathway approach to this exploratory WGS dataset of African myasthenic individuals, and comparing dichotomous subphenotypes, resulted in the identification of candidate genes and pathways that may contribute to OP-MG susceptibility. Overall, the hypotheses generated by this work remain to be verified by interrogating candidate gene and pathway expression in patient-derived extraocular muscle.
Collapse
Affiliation(s)
- Melissa Nel
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Nicola Mulder
- Computational Biology Division, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Tarin A Europa
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Jeannine M Heckmann
- Neurology Research Group, Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| |
Collapse
|
21
|
Nel M, Prince S, Heckmann JM. Profiling of patient-specific myocytes identifies altered gene expression in the ophthalmoplegic subphenotype of myasthenia gravis. Orphanet J Rare Dis 2019; 14:24. [PMID: 30696470 PMCID: PMC6352355 DOI: 10.1186/s13023-019-1003-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 01/21/2019] [Indexed: 01/31/2023] Open
Abstract
Background While extraocular muscles are affected early in myasthenia gravis (MG), but respond to treatment, we observe a high incidence of treatment-resistant ophthalmoplegia (OP-MG) among MG subjects with African genetic ancestry. Previously, using whole exome sequencing, we reported potentially functional variants which associated with OP-MG. The aim of this study was to profile the expression of genes harbouring the OP-MG associated variants using patient-derived subphenotype-specific ‘myocyte’ cultures. Methods From well-characterised MG patients we developed the ‘myocyte’ culture models by transdifferentiating dermal fibroblasts using an adenovirus expressing MyoD. These myocyte cultures were treated with homologous acetylcholine receptor antibody-positive myasthenic sera to induce muscle transcripts in response to an MG stimulus. Gene expression in myocytes derived from OP-MG (n = 10) and control MG subjects (MG without ophthalmoplegia; n = 6) was quantified using a custom qPCR array profiling 93 potentially relevant genes which included the putative OP-MG susceptibility genes and other previously reported genes of interest in MG and experimental autoimmune myasthenia gravis (EAMG). Results OP-MG myocytes compared to control MG myocytes showed altered expression of four OP-MG susceptibility genes (PPP6R2, CANX, FAM136A and FAM69A) as well as several MG and EAMG genes (p < 0.05). A correlation matrix of gene pair expression levels revealed that 15% of gene pairs were strongly correlated in OP-MG samples (r > 0.78, p < 0.01), but not in control MG samples. OP-MG susceptibility genes and MG-associated genes accounted for the top three significantly correlated gene pairs (r ≥ 0.98, p < 1 × 10− 6) reflecting crosstalk between OP-MG and myasthenia pathways, which was not evident in control MG cells. The genes with altered expression dynamics between the two subphenotypes included those with a known role in gangliosphingolipid biosynthesis, mitochondrial metabolism and the IGF1-signalling pathway. Conclusion Using a surrogate cell culture model our findings suggest that muscle gene expression and co-expression differ between OP-MG and control MG individuals. These findings implicate pathways not previously considered in extraocular muscle involvement in myasthenia gravis and will inform future studies. Electronic supplementary material The online version of this article (10.1186/s13023-019-1003-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Melissa Nel
- Neurology Research Group, Division of Neurology, E8-30, New Groote Schuur Hospital, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Sharon Prince
- Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa
| | - Jeannine M Heckmann
- Neurology Research Group, Division of Neurology, E8-30, New Groote Schuur Hospital, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa. .,Division of Neurology, E8-74, New Groote Schuur Hospital, Department of Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, 7925, South Africa.
| |
Collapse
|
22
|
Europa TA, Nel M, Heckmann JM. Myasthenic ophthalmoparesis: Time To resolution after initiating immune therapies. Muscle Nerve 2018; 58:542-549. [DOI: 10.1002/mus.26172] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 05/06/2018] [Accepted: 05/08/2018] [Indexed: 12/20/2022]
Affiliation(s)
- Tarin A. Europa
- Neurology Research Group, Division of Neurology, Department of Medicine; University of Cape Town; Cape Town South Africa
| | - Melissa Nel
- Neurology Research Group, Division of Neurology, Department of Medicine; University of Cape Town; Cape Town South Africa
| | - Jeannine M. Heckmann
- Neurology Research Group, Division of Neurology, Department of Medicine; University of Cape Town; Cape Town South Africa
| |
Collapse
|
23
|
Abstract
Objectives To describe the clinical profile, clinical outcomes and factors that may affect the outcome of juvenile myasthenia gravis (JMG) patients in southern China. Methods We reviewed information relating to JMG patients treated and evaluated at the First Affiliated Hospital, Sun Yat-sen University, between 1998 and 2015. The study involved 327 JMG patients who had been followed up for ≥1 year. Results Overall, 77.4% patients showed initial symptoms in the prepubertal period (<12 years). 306 patients showed only ocular symptoms at onset. By the final follow-up, 61 ocular myasthenia gravis (OMG) patients (61/306, 19.9%) had developed generalized myasthenia gravis (GMG). Anti-acetylcholine receptor antibodies (AChR-Ab) titer was an independent risk factor for generalization. Eleven patients (3.4%) experienced spontaneous remission, but four relapsed. Low-dose oral prednisone (0.25 mg/kg) was administered when symptoms did not significantly improve after pyridostigmine treatment. Immunosuppressants were administered when prednisone was unsatisfactory. Optimal outcome was achieved in 59.6% of patients. Specifically, 60 patients (18.3%) attained complete stable remission (CSR), 12 (3.7%) attained pharmaceutical remission (PR), and 123 (37.6%) attained minimal manifestation (MM). In total, 53 OMG patients (21.5%) attained CSR, a significantly higher proportion than among the GMG patients (8.6%, P = 0.009). Moreover, 67.2% of patients with duration <2 years showed significant clinical improvement compared with 46.3% of those with duration >2 years (P < 0.001). Thymectomy did not exhibit definite efficacy for JMG patients. Conclusion There was a low frequency of cases positive for AChR-Ab in the Chinese population. AChR-Ab titer was revealed as an independent risk factor for generalization. Low doses of prednisone could treat JMG effectively with few side effects.
Collapse
Affiliation(s)
- Xin Huang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory for Diagnosis and Treatment of Major Neurological Diseases, Guangzhou, China
| | - Yingkai Li
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Huiyu Feng
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Pei Chen
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Weibin Liu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory for Diagnosis and Treatment of Major Neurological Diseases, Guangzhou, China
| |
Collapse
|
24
|
Saidi T, Sivarasu S, Douglas TS. Open source modular ptosis crutch for the treatment of myasthenia gravis. Expert Rev Med Devices 2018; 15:137-143. [PMID: 29271663 DOI: 10.1080/17434440.2018.1421455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
INTRODUCTION Pharmacologic treatment of Myasthenia Gravis presents challenges due to poor tolerability in some patients. Conventional ptosis crutches have limitations such as interference with blinking which causes ocular surface drying, and frequent irritation of the eyes. To address this problem, a modular and adjustable ptosis crutch for elevating the upper eyelid in Myasthenia Gravis patients has been proposed as a non-surgical and low-cost solution. AREAS COVERED This paper reviews the literature on the challenges in the treatment of Myasthenia Gravis globally and focuses on a modular and adjustable ptosis crutch that has been developed by the Medical Device Laboratory at the University of Cape Town. EXPERT COMMENTARY The new medical device has potential as a simple, effective and unobtrusive solution to elevate the drooping upper eyelid(s) above the visual axis without the need for medication and surgery. Access to the technology is provided through an open source platform which makes it available globally. Open access provides opportunities for further open innovation to address the current limitations of the device, ultimately for the benefit not only of people suffering from Myasthenia Gravis but also of those with ptosis from other aetiologies.
Collapse
Affiliation(s)
- Trust Saidi
- a Department of Human Biology , Division of Biomedical Engineering, University of Cape Town , Cape Town , South Africa
| | - Sudesh Sivarasu
- a Department of Human Biology , Division of Biomedical Engineering, University of Cape Town , Cape Town , South Africa
| | - Tania S Douglas
- a Department of Human Biology , Division of Biomedical Engineering, University of Cape Town , Cape Town , South Africa
| |
Collapse
|
25
|
Heckmann JM, Nel M. A unique subphenotype of myasthenia gravis. Ann N Y Acad Sci 2017; 1412:14-20. [DOI: 10.1111/nyas.13471] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 08/14/2017] [Accepted: 08/18/2017] [Indexed: 12/26/2022]
Affiliation(s)
- Jeannine M. Heckmann
- Neurology Division, Department of Medicine; University of Cape Town, Groote Schuur Hospital; Cape Town South Africa
- Neurology Research Group, Department of Medicine; University of Cape Town; Cape Town South Africa
| | - Melissa Nel
- Neurology Research Group, Department of Medicine; University of Cape Town; Cape Town South Africa
| |
Collapse
|
26
|
The association between scabies and myasthenia gravis: A nationwide population-based cohort study. J Clin Neurosci 2017; 45:115-120. [PMID: 28890037 DOI: 10.1016/j.jocn.2017.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 08/10/2017] [Indexed: 12/24/2022]
Abstract
Scabies is an infectious inflammatory pruritic skin disease. Cytokine-mediated inflammatory processes contribute to the pathologic mechanism in scabies. Myasthenia gravis (MG) is also an autoimmune disease that is mediated by cytokines. The study aimed to investigate the association between scabies and myasthenia gravis. We conducted a nationwide population-based cohort study utilized data from the National Health Insurance Research Database (NHIRD) of Taiwan. Patients with scabies (n=5429) and control subjects without scabies (n=20,176) were enrolled. We tracked the subjects in both groups for a 7-year period to identify new onset MG. Cox regression analysis was performed to calculate the hazard ratio (HR) for MG. A total of 25,605 patients were enrolled in the study, including 5429 patients in the scabies group and 20,176 in the control group. There were 40 (0.7%) patients from the scabies group and 84 (0.4%) subjects from the control group who were newly diagnosed with MG during the 7-year follow-up period. The scabies patients had a significantly increased risk of MG, with an adjusted HR of 1.27 (95% confidence interval [CI] 1.01-1.89). As such, prompt diagnosis and treatment of scabies may decrease the risk of subsequent MG.
Collapse
|
27
|
Affiliation(s)
- Jeannine M Heckmann
- Division of Neurology, Department of Medicine, University of Cape Town, Cape Town, South Africa.
| |
Collapse
|
28
|
Bettini M, Chaves M, Cristiano E, Pagotto V, Perez L, Giunta D, Rugiero M. Incidence of Autoimmune Myasthenia Gravis in a Health Maintenance Organization in Buenos Aires, Argentina. Neuroepidemiology 2017. [PMID: 28641305 DOI: 10.1159/000477733] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Different epidemiological studies, especially in Europe, have estimated the incidence density of myasthenia gravis (MG) to range between 1.7 and 21.3/1,000,000/person-year; however, data from regions such as Latin America are scarce. This study is aimed at estimating the incidence and prevalence of acquired MG in Buenos Aires, Argentina. METHODS The study population comprised of affiliates of the Italian Hospital Medical Care Program, a prepaid health maintenance organization located in Buenos Aires. The evaluation method for case detection included a retrospective search from January 1, 2006, through December 31, 2012. RESULTS Of the 60 cases identified, 36 (60%) were females. The median age at diagnosis was 69 years (IQR 51.5-79). The mean age at diagnosis was 63.3 years (SD ±20). A total of 28 patients (46.7%) had generalized MG and 32 had ocular MG (53.3%). Thirty five patients (58.3%) had acetylcholine receptor antibodies and 2 (3.3%) had muscle-specific receptor tyrosine kinase antibodies. The crude incidence density (ID) of MG was 61.33 per 1,000,000 person-years (95% CI 47.62-79.99). The adjusted ID for the Argentinean population was 38.8 per 1,000,000 person-years (95% CI 27.09-50.51) and for the Buenos Aires population was 47.49 (95% CI 34.73-60.25). CONCLUSIONS The results obtained are similar to those published for other geographical areas.
Collapse
|
29
|
Nel M, Jalali Sefid Dashti M, Gamieldien J, Heckmann JM. Exome sequencing identifies targets in the treatment-resistant ophthalmoplegic subphenotype of myasthenia gravis. Neuromuscul Disord 2017; 27:816-825. [PMID: 28673556 DOI: 10.1016/j.nmd.2017.06.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 06/13/2017] [Accepted: 06/14/2017] [Indexed: 12/25/2022]
Abstract
Treatment-resistant ophthalmoplegia (OP-MG) is not uncommon in individuals with African genetic ancestry and myasthenia gravis (MG). To identify OP-MG susceptibility genes, extended whole exome sequencing was performed using extreme phenotype sampling (11 OP-MG vs 4 control-MG) all with acetylcholine receptor-antibody positive MG. This approach identified 356 variants that were twice as frequent in OP-MG compared to control-MG individuals. After performing probability test estimates and filtering variants according to those 'suggestive' of association with OP-MG (p < 0.05), only three variants remained which were expressed in extraocular muscles. Validation in 25 OP-MG and 50 control-MG cases supported the association of DDX17delG (p = 0.014) and SPTLC3insACAC (p = 0.055) with OP-MG, but ST8SIA1delCCC could not be verified by Sanger sequencing. A parallel approach, using a semantic model informed by current knowledge of MG-pathways, identified an African-specific interleukin-6 receptor (IL6R) variant, IL6R c.*3043 T>C, that was more frequent in OP-MG compared to control-MG cases (p = 0.069) and population controls (p = 0.043). A weighted genetic risk score, derived from the odds ratios of association of these variants with OP-MG, correlated with the OP-MG phenotype as opposed to control MG. This unbiased approach implicates several potentially functional gene variants in the gangliosphingolipid and myogenesis pathways in the development of the OP-MG subphenotype.
Collapse
Affiliation(s)
- Melissa Nel
- Neurology Division, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | | | - Junaid Gamieldien
- South African National Bioinformatics Institute, University of the Western Cape, Bellville, South Africa
| | - Jeannine M Heckmann
- Neurology Division, Department of Medicine, University of Cape Town, Cape Town, South Africa.
| |
Collapse
|
30
|
Popperud TH, Boldingh MI, Brunborg C, Faiz KW, Heldal AT, Maniaol AH, Müller KI, Rasmussen M, Øymar K, Kerty E. Juvenile myasthenia gravis in Norway: A nationwide epidemiological study. Eur J Paediatr Neurol 2017; 21:312-317. [PMID: 27666466 DOI: 10.1016/j.ejpn.2016.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 08/17/2016] [Accepted: 09/03/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND The aim of this study was to assess the incidence rate and prevalence of autoimmune myasthenia gravis (MG) among children in Norway. METHODS This retrospective population-based study was performed in Norway from January 2012 to December 2013. Cases of juvenile MG (JMG) with onset < 18 years were identified through searches in coding systems of electronic patient records at the 15 main hospitals in Norway from 1989 to 2013. In addition, the acetylcholine receptor antibody database at Haukeland University Hospital and the clinical nationwide MG database at Oslo University Hospital were searched for cases of JMG. Diagnosis and age at onset were verified through medical records. Incidence and prevalence rates were calculated using the Norwegian population as reference. RESULTS In total 63 unique JMG cases were identified. This corresponds to an average annual incidence rate of 1.6 per million. Incidence rate was stable over the study period. Prevalence of JMG was 3.6-13.8 per million. Females constituted the majority of JMG cases (55 vs 8 males). The risk of JMG was higher among females both in the postpubertal and prepubertal group (p < 0.001 and p = 0.02, respectively). CONCLUSION This study confirms the rarity of JMG in Norway, especially among males, and shows a stable incidence rate over the last 25 years.
Collapse
Affiliation(s)
- T H Popperud
- Department of Neurology, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
| | - M I Boldingh
- Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - C Brunborg
- Oslo Centre for Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, Oslo, Norway
| | - K W Faiz
- Department of Neurology, Akershus University Hospital, Lørenskog, Norway
| | - A T Heldal
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - A H Maniaol
- Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - K I Müller
- Department of Neurology and National Neuromuscular Centre, University Hospital of North Norway, Tromsø, Norway; Department of Clinical Medicine, UiT - The Artic University of Norway, Tromsø, Norway
| | - M Rasmussen
- Department of Clinical Neuroscience for Children, Section for Child Neurology, Oslo University Hospital, Oslo, Norway; Unit for Hereditary and Inborn Neuromuscular Disorders, Department of Neurology, Oslo University Hospital, Oslo, Norway
| | - K Øymar
- Department of Clinical Medicine, University of Bergen, Bergen, Norway; Department of Pediatrics, Stavanger University Hospital, Stavanger, Norway
| | - E Kerty
- Department of Neurology, Oslo University Hospital, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| |
Collapse
|
31
|
Huda S, Woodhall MR, Vincent A, Heckmann JM. Characteristics Of acetylcholine-receptor-antibody-negative myasthenia gravis in a South African cohort. Muscle Nerve 2016; 54:1023-1029. [PMID: 27105303 DOI: 10.1002/mus.25154] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 04/16/2016] [Accepted: 04/20/2016] [Indexed: 11/10/2022]
Abstract
INTRODUCTION In this study we determined the frequencies of antibodies (Abs) directed against muscle-specific kinase (MuSK) and lipoprotein receptor-related protein 4 (LRP4) in the sera of a South African cohort with acetylcholine receptor (AChR)-antibody-negative generalized MG and determined outcomes to therapies. METHODS Sera negative by commercial AChR radioimmunoassay (RIA) were tested by MuSK RIA (n = 30; 2006-2012) and AChR, MuSK, and LRP4 RIA with or without cell-based assays (CBA) (n = 53; 2012-2015). RESULTS AChR-Abs were detected in 4 of 53 and MuSK-Abs in 20 of 83 (24%) cases. Thirty-six of 53 (68%) were triple seronegative (triple-SNMG) for MuSK, AChR, and LRP4-Abs. When compared with triple-SNMG, individuals with MuSK-MG had a younger onset age (P = 0.008), a greater likelihood of African genetic ancestry (P = 0.008), and 4-fold higher odds of reaching MGFA grade IVB/V (P = 0.018), but were also 9-fold more likely to reach at least minimal manifestations status after ≥12 months of therapy (P = 0.003). CONCLUSIONS Individuals with African genetic ancestry and severe bulbar/respiratory AChR-Ab-negative MG are likely to have MuSK-MG, but most respond favorably to maintenance immunotherapies. Muscle Nerve 54: 1023-1029, 2016.
Collapse
Affiliation(s)
- Saif Huda
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Mark R Woodhall
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK
| | - Jeannine M Heckmann
- Division of Neurology, E8-74, Department of Medicine, University of Cape Town, South Africa
| |
Collapse
|
32
|
Findlay M, Heckmann JM, Sivarasu S. Three-Dimensional Printed Patient Specific Ptosis Crutches as a Nonsurgical Solution for Elevating Upper Eyelids in Myasthenia Gravis Patients1. J Med Device 2016. [DOI: 10.1115/1.4033225] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Megan Findlay
- Medical Devices Laboratory, Division of Biomedical Engineering, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa
| | - Jeannine M. Heckmann
- Division of Neurology, Department of Medicine, University of Cape Town, Cape Town 7925, South Africa
| | - Sudesh Sivarasu
- Medical Devices Laboratory, Division of Biomedical Engineering, Department of Human Biology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa e-mail:
| |
Collapse
|
33
|
The African-387 C>T TGFB1 variant is functional and associates with the ophthalmoplegic complication in juvenile myasthenia gravis. J Hum Genet 2015; 61:307-16. [PMID: 26632886 DOI: 10.1038/jhg.2015.146] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 11/07/2015] [Accepted: 11/10/2015] [Indexed: 02/03/2023]
Abstract
Although extraocular muscles are commonly affected by myasthenia gravis (MG) at presentation, a treatment-resistant ophthalmoplegic complication of MG (OP-MG) occurs in younger patients with African-genetic ancestry. In MG, pathogenic antibodies activate complement-mediated muscle damage and this may be potentiated in some OP-MG cases because of relative deficiency of decay-accelerating factor/CD55. Extending this argument, we hypothesized that OP-MG individuals may harbor African-specific polymorphisms in key genes influencing extraocular muscle remodeling. We screened the regulatory region of the transforming growth factor beta-1 (TGFB1) gene encoding the cytokine pivotal in muscle healing responses. We show the frequency of an African-specific polymorphism TGFB1 c.-387 T (rs11466316) among South Africans with African-genetic ancestry is higher than 1000 Genomes African controls (17.2% vs 4.8%; P<1 × 10(-7)), and associates with juvenile OP-MG (28%; P=0.043). Further, TGFB1 -387 C>T is functional because it represses the TGFB1 promoter construct basal activity by fivefold, and OP-MG fibroblasts (-387 C/T or T/T) have lower basal TGFB1 mRNA transcripts compared with controls (-387 C/C)(P=0.001). Co-transfections with Sp1 show less responsiveness of the -387 T promoter compared with wild-type -387 C (P=0.015). Our findings suggest that population-specific alleles may lower TGFB1 expression, thereby influencing OP-MG susceptibility by inhibiting extraocular muscle CD55 upregulation and/or altered endplate remodeling.
Collapse
|