Article
Clinical Neurology
Young Nam Kwon, Mark Woodhall, Jung-Joon Sung, Kwang-Kuk Kim, Young-Min Lim, Hyunjin Kim, Jee-Eun Kim, Seol-Hee Baek, Byung-Jo Kim, Jin-Sung Park, Hung Youl Seok, Dae-Seong Kim, Ohyun Kwon, Kee Hong Park, Eunhee Sohn, Jong Seok Bae, Byung-Nam Yoon, Nam-Hee Kim, Suk-Won Ahn, Kyomin Choi, Jeeyoung Oh, Hyung Jun Park, Kyong Jin Shin, Sanggon Lee, Jinseok Park, Seung Hyun Kim, Jung Im Seok, Dae Woong Bae, Jae Young An, In Soo Joo, Seok-Jin Choi, Tai-Seung Nam, Sunyoung Kim, Ki-Jong Park, Ki-Han Kwon, Patrick Waters, Yoon-Ho Hong
Summary: This study aimed to evaluate the diagnostic accuracy of ELISA for anti-MuSK antibody in AChR antibody-negative generalized MG patients and investigate the clinical contexts for the diagnosis of MuSK MG. The results showed that the positive results of ELISA were mostly consistent with CBA and RIPA. The most common differential diagnosis was motor neuron disease. These findings are of great importance for the diagnosis of MuSK MG in clinical practice.
JOURNAL OF NEUROLOGY
(2023)
Article
Clinical Neurology
Yufan Zhou, Jialin Chen, Zunbo Li, Song Tan, Chong Yan, Sushan Luo, Lei Zhou, Jie Song, Xiao Huan, Ying Wang, Chongbo Zhao, Wenshuang Zeng, Jianying Xi
Summary: Antibodies to MuSK can identify a rare subtype of myasthenia gravis called MuSK-MG. The age of onset of MuSK-MG in the Chinese population is unknown. In this retrospective multicenter study, it was found that MuSK-MG patients typically have an acute onset with predominant involvement of bulbar and respiratory muscles. Very-late-onset patients tend to have early involvement of limb, bulbar, and respiratory muscles, suggesting an earlier use of rituximab. Regardless of age at onset, the majority of MuSK-MG patients can benefit from rituximab treatment.
FRONTIERS IN NEUROLOGY
(2022)
Article
Clinical Neurology
Yohei Harada, Margaret Bettin, Vern C. Juel, Lisa D. Hobson-Webb, Shruti M. Raja, Donald B. Sanders, Janice M. Massey
Summary: The aim of this study was to describe the course of MMG during pregnancy and within 6 months postpartum and document any effect on fetal health. A retrospective review of medical records was performed and included 14 pregnancies in 10 MMG patients. Results showed that MMG patients may experience worsening symptoms or develop initial symptoms during pregnancy or postpartum. Pregnant patients with MMG may require more aggressive medical therapy.
Article
Clinical Neurology
Gregorio Spagni, Matteo Gastaldi, Pietro Businaro, Zeineb Chemkhi, Cinzia Carrozza, Giovanni Mascagna, Silvia Falso, Silvia Scaranzin, Diego Franciotta, Amelia Evoli, Valentina Damato
Summary: This study compared the performance of fixed and live cell-based assays in patients with radioimmunoassay-double seronegative myasthenia gravis (dSN-MG). The results showed that the live cell-based assay had a higher ability to detect antibodies in dSN samples. In addition, the live assay was able to detect antibodies that were negative in the fixed assay, further increasing the antibody detection rate.
NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION
(2023)
Article
Medicine, General & Internal
Rika Yamashita, Mikito Shimizu, Kousuke Baba, Goichi Beck, Makoto Kinoshita, Tatsusada Okuno, Osamu Higuchi, Hideki Mochizuki
Summary: This case report presents a 62-year-old patient with MG who tested positive for anti-MuSK antibodies, as well as anti-Lrp4 and anti-titin antibodies. The patient had a history of intermittent double vision and ptosis for 10 years, which eventually led to MG crisis, showcasing the unique characteristics of anti-MuSK-antibody positive MG accompanied by anti-Lrp4 and anti-titin antibodies.
Article
Clinical Neurology
Qi Huang, Feng Li, Song Zhao
Summary: This study investigated the clinical characteristics, treatments, and outcomes of patients with MuSK-MG. The results showed that female patients were more prevalent and the disease progressed rapidly to a generalized state. Although approximately 50% of patients achieved a favorable outcome with immunosuppressants, complete stable remission was rare.
Review
Immunology
Aigli G. Vakrakou, Eleni Karachaliou, Elisabeth Chroni, Vasiliki Zouvelou, Dimitrios Tzanetakos, Stavroula Salakou, Marianna Papadopoulou, Socrates Tzartos, Konstantinos Voumvourakis, Constantinos Kilidireas, Sotirios Giannopoulos, Georgios Tsivgoulis, John Tzartos
Summary: Muscle-specific kinase (MuSK) Myasthenia Gravis (MG) is an antibody-mediated disease characterized by focal muscle weakness and fatigability. The pathogenic antibodies, mostly IgG4, interfere with the interaction between MuSK and its binding partners. Unlike Acetylcholine receptor (AChR) MG, MuSK-MG has less thymus involvement and distinct HLA alleles. Classical treatments are usually less effective in MuSK-MG, but plasmapheresis and rituximab have shown exceptional clinical response.
FRONTIERS IN IMMUNOLOGY
(2023)
Article
Medicine, General & Internal
Do-Hyung Kim, Hyeon Cheol Roh, Shin Yeop Oh
Summary: This study investigated the clinical features of ocular myasthenia gravis (OMG) in ophthalmology. A total of 28 patients with ptosis or diplopia were included and analyzed. The patients were divided into two groups based on test results and compared according to clinical symptoms. It was found that ptosis and diplopia were significantly higher in the positive results group, and both horizontal and vertical diplopia were significantly higher in patients with higher AchR Ab titer. The study suggests considering OMG when patients present with ptosis and diplopia, especially vertical diplopia, after excluding cranial nerve palsy.
Article
Clinical Neurology
Sijia Zhao, Kai Zhang, Kaixi Ren, Jiarui Lu, Chao Ma, Cong Zhao, Zhuyi Li, Jun Guo
Summary: Patients with MuSK-MG showed a female predominance, with an average age of onset at 40.28 years and a median disease course of 30.50 months. Ocular manifestation was the most common onset symptom, and there was an obvious positive correlation between QMG score and MuSK-ab titer in all patients.
Article
Multidisciplinary Sciences
Dana L. E. Vergoossen, Jaap J. Plomp, Christoph Gstottner, Yvonne E. Fillie-Grijpma, Roy Augustinus, Robyn Verpalen, Manfred Wuhrer, Paul W. H. Parren, Elena Dominguez-Vega, Silvere M. van der Maarel, Jan J. Verschuuren, Maartje G. Huijbers
Summary: This study demonstrates that the process of Fab-arm exchange in IgG4 amplifies autoantibody pathogenicity in autoimmune diseases, such as muscle-specific kinase (MuSK) myasthenia gravis. Monovalent anti-MuSK IgG4 antibodies were found to cause rapid and severe muscle weakness, indicating functional monovalency as a pathogenic mechanism in IgG4-mediated autoimmune diseases.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Immunology
Ying Zhu, Benqiao Wang, Yuehan Hao, Ruixia Zhu
Summary: Multiple reports have shown the co-existence of autoimmune diseases and myasthenia gravis (MG). This review explores the clinical presentations of autoimmune diseases in MG and investigates whether the presence of autoimmune diseases affects the severity and treatment strategies of MG. The review reveals a higher frequency of autoimmune diseases in MG patients, particularly in women. Most autoimmune comorbidities are linked to AChR-MG, with thyroid disorders, systemic lupus erythematosus, and vitiligo being the most common. MG can also coexist with neurological autoimmune diseases, with neuromyelitis optica (NMO) being the most common. The review suggests that autoimmune diseases occur more often in early-onset MG and do not influence the clinical course of MG.
FRONTIERS IN IMMUNOLOGY
(2023)
Article
Biochemistry & Molecular Biology
Umberto Basile, Cecilia Napodano, Francesca Gulli, Krizia Pocino, Riccardo Di Santo, Laura Todi, Valerio Basile, Carlo Provenzano, Gabriele Ciasca, Mariapaola Marino
Summary: The study found that in both MuSK-MG and AChR antibody-positive MG patients, the hybrid/total ratio is similar to the distribution in normal individuals, but it is only positively correlated with anti-MuSK titer in terms of specific immune reactivity. As disease severity increases, the hybrid/total ratio also gradually increases, indicating the involvement of hybrid IgG4 molecules in the pathogenic immune reactivity against MuSK. Further research is needed to strengthen the significance of this lesser-known biomarker, but it is believed to have diagnostic and prognostic potential for the management of MuSK-MG.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2021)
Article
Clinical Neurology
Jakob Rath, Manuela Taborsky, Bernhard Moser, Gudrun Zulehner, Rosa Weng, Martin Krenn, Hakan Cetin, Jose Ramon Matilla, Leonhard Muellauer, Fritz Zimprich
Summary: This study investigated the short- and long-term outcomes of thymectomy in patients with acetylcholine receptor antibody-positive myasthenia gravis (MG). The results showed that the sustained long-term clinical response after thymectomy is lower than the initial response rates would suggest. None of the evaluated clinical factors predicted a worse outcome, supporting the current clinical practice of patient selection for thymectomy. The relative decline of AChR-Abs after surgery appears to be a promising prognostic marker.
EUROPEAN JOURNAL OF NEUROLOGY
(2022)
Article
Biotechnology & Applied Microbiology
Sangwook Oh, Xuming Mao, Silvio Manfredo-Vieira, Jinmin Lee, Darshil Patel, Eun Jung Choi, Andrea Alvarado, Ebony Cottman-Thomas, Damian Maseda, Patricia Y. Y. Tsao, Christoph T. T. Ellebrecht, Sami L. L. Khella, David P. P. Richman, Kevin C. C. O'Connor, Uri Herzberg, Gwendolyn K. K. Binder, Michael C. C. Milone, Samik Basu, Aimee S. S. Payne
Summary: Engineered T cells expressing MuSK-CAART effectively target B cells expressing anti-MuSK autoantibodies, reducing muscle weakness caused by autoimmune disease.
NATURE BIOTECHNOLOGY
(2023)
Article
Medicine, General & Internal
Hyuna Kim, Shin Yeop Oh
Summary: This study investigated the clinical features and diagnosis process of ocular myasthenia gravis (OMG) in an ophthalmology department. Patients were divided into two groups based on serologic test results for comparison. The study found that patients with two clinical symptoms had significantly higher AchR Ab titers than those with only one clinical symptom.
