{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T09:30:13Z","timestamp":1772789413835,"version":"3.50.1"},"reference-count":30,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T00:00:00Z","timestamp":1772755200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>The coexistence of myasthenia gravis (MG) with other IgG-mediated autoimmune diseases represents a clinically heterogeneous condition, driven by pathogenic autoantibodies. Efgartigimod, a neonatal Fc receptor antagonist, has the ability to clear all IgG subclasses. Here, we report four cases of MG concomitant with IgG-mediated autoimmune diseases, specifically idiopathic inflammatory myopathies (IIM), Isaacs syndrome, autoimmune encephalitis (AE), and IgG4-related disease (IgG4-RD). All of them demonstrated a favorable therapeutic response to efgartigimod, with marked improvement in QMG and MG-ADL scores, along with disease-specific clinical or laboratory manifestations of the overlapping autoimmune conditions. These cases provide preliminary evidence supporting efgartigimod as a promising treatment option for patients with MG complicated by IgG-mediated autoimmune diseases.<\/jats:p>","DOI":"10.3389\/fimmu.2026.1788550","type":"journal-article","created":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T06:43:00Z","timestamp":1772779380000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Case Report: Dual response to efgartigimod in myasthenia gravis and comorbid autoimmune disorders: a case series"],"prefix":"10.3389","volume":"17","author":[{"given":"Yunjia","family":"Li","sequence":"first","affiliation":[{"name":"Department of Neurology, The First Affiliated Hospital of China Medical University","place":["Shenyang, China"]},{"name":"Key Laboratory of Neurological Disease Big Data of Liaoning Province","place":["Shenyang, China"]},{"name":"Clinical Medical Research Center for Difficult and Serious Diseases of the Nervous Systems","place":["Shenyang, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yingying","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Neurology, The First Affiliated Hospital of China Medical University","place":["Shenyang, China"]},{"name":"Key Laboratory of Neurological Disease Big Data of Liaoning Province","place":["Shenyang, China"]},{"name":"Clinical Medical Research Center for Difficult and Serious Diseases of the Nervous Systems","place":["Shenyang, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Neurology, The First Affiliated Hospital of China Medical University","place":["Shenyang, China"]},{"name":"Key Laboratory of Neurological Disease Big Data of Liaoning Province","place":["Shenyang, China"]},{"name":"Clinical Medical Research Center for Difficult and Serious Diseases of the Nervous Systems","place":["Shenyang, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruixia","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Neurology, The First Affiliated Hospital of China Medical University","place":["Shenyang, China"]},{"name":"Key Laboratory of Neurological Disease Big Data of Liaoning Province","place":["Shenyang, China"]},{"name":"Clinical Medical Research Center for Difficult and Serious Diseases of the Nervous Systems","place":["Shenyang, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,3,6]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"30","DOI":"10.1038\/s41572-019-0079-y","article-title":"Myasthenia gravis","volume":"5","author":"Gilhus","year":"2019","journal-title":"Nat Rev Dis Primers"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2023.1223322","article-title":"Clinical features of myasthenia gravis with neurological and systemic autoimmune diseases","volume":"14","author":"Zhu","year":"2023","journal-title":"Front Immunol"},{"key":"B3","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.jaut.2014.05.001","article-title":"Myasthenia Gravis: Paradox versus paradigm in autoimmunity","volume":"52","author":"Berrih-Aknin","year":"2014","journal-title":"J Autoimmun"},{"key":"B4","doi-asserted-by":"publisher","first-page":"798","DOI":"10.1038\/s41577-021-00543-w","article-title":"Autoantibodies in neurological disease","volume":"21","author":"Pruss","year":"2021","journal-title":"Nat Rev Immunol"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1097\/JTO.0000000000000300","article-title":"Paraneoplastic disorders in thymoma patients","volume":"9","author":"Evoli","year":"2014","journal-title":"J Thorac Oncol"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1016\/j.autrev.2019.102368","article-title":"Thyroid disorders in patients with myasthenia gravis: A systematic review and meta-analysis","volume":"18","author":"Song","year":"2019","journal-title":"Autoimmun Rev"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1177\/1756286421997381","article-title":"The importance of FcRn in neuro-immunotherapies: From IgG catabolism, FCGRT gene polymorphisms, IVIg dosing and efficiency to specific FcRn inhibitors","volume":"14","author":"Dalakas","year":"2021","journal-title":"Ther Adv Neurological. 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