{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,17]],"date-time":"2026-06-17T16:06:22Z","timestamp":1781712382533,"version":"3.54.5"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T00:00:00Z","timestamp":1770595200000},"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. Neurol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>\n                      Since its initial description in 2016,\n                      <jats:italic>DYT-KMT2B<\/jats:italic>\n                      has emerged as one of the most common genetic causes of early-onset dystonia. Subsequent reports have expanded its phenotypic spectrum, frequently including neurodevelopmental features. Deep brain stimulation of the globus pallidus internus (GPi DBS) has become a therapeutic mainstay; however, most published data are based on single cases or short-term observations, and long-term outcomes remain poorly characterized.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We report the clinical course and response to GPi DBS in nine patients with\n                      <jats:italic>KMT2B<\/jats:italic>\n                      variants prospectively followed at two Austrian national reference centers for rare movement disorders. Long-term follow-up data (range: 5\u201320 years) were available for six patients. Clinical features and treatment outcomes were compared with previously published cohorts.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Non-motor features such as developmental delay, intellectual disability, and epilepsy were more frequent in our cohort than in earlier reports. All patients developed generalized dystonia and bulbar involvement over time, emphasizing the progressive nature of the disease. Despite secondary symptom worsening during long-term follow-up, GPi DBS preserved ambulation in three patients and enabled sustained recovery of walking ability in two, maintaining functional independence. Surgical correction of foot deformities further supported mobility. Notably,\n                      <jats:italic>KMT2B<\/jats:italic>\n                      variants were identified upon genetic re-evaluation in two patients previously diagnosed with dyskinetic cerebral palsy.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>\n                      Our long-term data underscore the progressive but heterogeneous course of\n                      <jats:italic>DYT-KMT2B<\/jats:italic>\n                      . GPi DBS offers durable clinical benefits, particularly when initiated before loss of ambulation. Early surgical intervention and multidisciplinary management are essential to optimize long-term outcomes.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fneur.2026.1727854","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T05:22:05Z","timestamp":1770614525000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["KMT2B-related disorders in Austria: clinical features and long-term outcome after deep brain stimulation"],"prefix":"10.3389","volume":"17","author":[{"given":"Elisabetta","family":"Indelicato","sequence":"first","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sandy","family":"Siegert","sequence":"additional","affiliation":[{"name":"Center for Rare Neurological Disorders with a Focus on Rare Pediatric Movement Disorders, Division of Pediatric Pulmonology, Allergology and Endocrinology, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna","place":["Vienna, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Agnes","family":"Langer","sequence":"additional","affiliation":[{"name":"Department of Neurology, Medical University of Vienna","place":["Vienna, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Hussl","sequence":"additional","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philipp","family":"Mahlknecht","sequence":"additional","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katherina","family":"Mair","sequence":"additional","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna","family":"Eberl","sequence":"additional","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Zech","sequence":"additional","affiliation":[{"name":"Institute of Neurogenomics, Helmholtz Munich","place":["Neuherberg, Germany"]},{"name":"Institute of Human Genetics, Technical University of Munich, School of Medicine","place":["Munich, Germany"]},{"name":"Institute for Advanced Study, Technical University of Munich","place":["Garching, Germany"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wolfgang M.","family":"Schmidt","sequence":"additional","affiliation":[{"name":"Neuromuscular Research Department, Center for Anatomy and Cell Biology, Medical University of Vienna","place":["Vienna, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sylvia","family":"Boesch","sequence":"additional","affiliation":[{"name":"Center for Rare Movement Disorders Innsbruck, Department of Neurology, Medical University Innsbruck","place":["Innsbruck, Austria"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,2,9]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"19","DOI":"10.1007\/s11910-019-1007-y","article-title":"Update on KMT2B-related dystonia","author":"Zech","year":"2019","journal-title":"Curr Neurol Neurosci 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