{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T16:29:33Z","timestamp":1774801773985,"version":"3.50.1"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,8,24]],"date-time":"2021-08-24T00:00:00Z","timestamp":1629763200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>(1) Background: Immune\u2013mediated necrotizing myopathy (IMNM) is a rare form of inflammatory muscle disease which is even more rare in pediatric patients. To increase the knowledge of juvenile IMNM, we here present the clinical findings on long-term follow-up, myopathological changes, and therapeutic strategies in two juvenile patients. (2) Methods: Investigations included phenotyping, determination of antibody status, microscopy on muscle biopsies, MRI, and response to therapeutic interventions. (3) Results: Anti-signal recognition particle (anti-SRP54) and anti- 3-hydroxy-3-methylglutarly coenzyme A reductase (anti-HMGCR) antibodies (Ab) were detected in the patients. Limb girdle presentation, very high CK-levels, and a lack of skin rash at disease-manifestation and an absence of prominent inflammatory signs accompanied by an abnormal distribution of \u03b1-dystroglycan in muscle biopsies initially hinted toward a genetically caused muscle dystrophy. Further immunostaining studies revealed an increase of proteins involved in chaperone-assisted autophagy (CASA), a finding already described in adult IMNM-patients. Asymmetrical muscular weakness was present in the anti-SRP54 positive Ab patient. After initial stabilization under therapy with intravenous immunoglobulins and methotrexate, both patients experienced a worsening of their symptoms and despite further therapy escalation, developed a permanent reduction of their muscle strength and muscular atrophy. (4) Conclusions: Diagnosis of juvenile IMNM might be complicated by asymmetric muscle weakness, lack of cutaneous features, absence of prominent inflammatory changes in the biopsy, and altered \u03b1-dystroglycan.<\/jats:p>","DOI":"10.3390\/children8090721","type":"journal-article","created":{"date-parts":[[2021,8,24]],"date-time":"2021-08-24T22:12:22Z","timestamp":1629843142000},"page":"721","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Clinical Course, Myopathology and Challenge of Therapeutic Intervention in Pediatric Patients with Autoimmune-Mediated Necrotizing Myopathy"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0737-6142","authenticated-orcid":false,"given":"Adela","family":"Della Marina","sequence":"first","affiliation":[{"name":"Centre for Neuromuscular Disorders and Centre for Translational Neuro- and Behavioral Sciences, Department of Pediatric Neurology University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marc","family":"Pawlitzki","sequence":"additional","affiliation":[{"name":"Department of Child and Adolescent Psychiatry and Psychotherapy, University Hospital M\u00fcnster,  48149 M\u00fcnster, Germany"},{"name":"Department of Neurology with Institute of Translational Neurology, University Hospital M\u00fcnster,  48149 M\u00fcnster, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tobias","family":"Ruck","sequence":"additional","affiliation":[{"name":"Department of Neurology with Institute of Translational Neurology, University Hospital M\u00fcnster,  48149 M\u00fcnster, Germany"},{"name":"Department of Neurology, University Hospital D\u00fcsseldorf, Heinrich-Heine-University D\u00fcsseldorf,  40225 D\u00fcsseldorf, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7988-5224","authenticated-orcid":false,"given":"Andreas","family":"van Baalen","sequence":"additional","affiliation":[{"name":"Clinic for Child and Adolescent Medicine II, University Hospital Schleswig-Holstein, 24105 Kiel, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nadine","family":"Vogt","sequence":"additional","affiliation":[{"name":"Clinic for Child and Adolescent Medicine II, University Hospital Schleswig-Holstein, 24105 Kiel, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bernd","family":"Schweiger","sequence":"additional","affiliation":[{"name":"Institute of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Swantje","family":"Hertel","sequence":"additional","affiliation":[{"name":"Centre for Neuromuscular Disorders and Centre for Translational Neuro- and Behavioral Sciences, Department of Pediatric Neurology University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9629-7053","authenticated-orcid":false,"given":"Heike","family":"K\u00f6lbel","sequence":"additional","affiliation":[{"name":"Centre for Neuromuscular Disorders and Centre for Translational Neuro- and Behavioral Sciences, Department of Pediatric Neurology University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heinz","family":"Wiendl","sequence":"additional","affiliation":[{"name":"Department of Neurology with Institute of Translational Neurology, University Hospital M\u00fcnster,  48149 M\u00fcnster, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Corinna","family":"Preu\u00dfe","sequence":"additional","affiliation":[{"name":"Department of Neuropathology, Humboldt-Universit\u00e4t zu Berlin and Berlin Institute of Health, Charit\u00e9-Universit\u00e4tsmedizin Berlin, 10117 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreas","family":"Roos","sequence":"additional","affiliation":[{"name":"Centre for Neuromuscular Disorders and Centre for Translational Neuro- and Behavioral Sciences, Department of Pediatric Neurology University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"},{"name":"Children\u2019s Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulrike","family":"Schara-Schmidt","sequence":"additional","affiliation":[{"name":"Centre for Neuromuscular Disorders and Centre for Translational Neuro- and Behavioral Sciences, Department of Pediatric Neurology University Hospital Essen, University Duisburg-Essen, 45147 Essen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1111\/nan.12528","article-title":"Histological heterogeneity in a large clinical cohort of juvenile idiopathic inflammatory myopathy: Analysis by myositis autoantibody and pathological features","volume":"45","author":"Yasin","year":"2019","journal-title":"Neuropathol. 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