{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T04:48:08Z","timestamp":1782535688084,"version":"3.54.5"},"reference-count":24,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,6,22]],"date-time":"2026-06-22T00:00:00Z","timestamp":1782086400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100030680","name":"Fu-Jen Catholic University Hospital","doi-asserted-by":"crossref","award":["PL-202208045-V (No. FJUH-111-046)"],"award-info":[{"award-number":["PL-202208045-V (No. FJUH-111-046)"]}],"id":[{"id":"10.13039\/100030680","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100030680","name":"Fu-Jen Catholic University Hospital","doi-asserted-by":"crossref","award":["PL-202308049-V (No. FJUH-112-049)"],"award-info":[{"award-number":["PL-202308049-V (No. FJUH-112-049)"]}],"id":[{"id":"10.13039\/100030680","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Fatigue and muscle wasting are common clinical manifestations of inherited and acquired neuromuscular disorders, including peripheral neuropathies, neuromuscular junction disorders, and myopathies. These conditions encompass a wide disease spectrum with variable prognoses, making accurate diagnosis essential for appropriate management. Congenital myasthenic syndromes (CMSs) are rare, inherited disorders characterized by impaired neuromuscular transmission. Although symptoms often begin in infancy or early childhood, later onset during adolescence or adulthood is increasingly recognized. Clinical phenotypes vary according to the underlying molecular defect, but fatigable weakness predominantly affecting axial and proximal limb muscles is a hallmark feature. We report an adolescent male who developed progressive proximal muscle weakness and wasting over several years, resulting in significant functional impairment. Initial evaluation suggested limb\u2013girdle muscular dystrophy. However, comprehensive investigations, including whole-exome sequencing, identified a heterozygous CHRNB1 mutation consistent with postsynaptic CMS. Targeted pharmacological therapy led to clinical improvement. This case highlights the importance of considering CMS in patients presenting with limb\u2013girdle weakness and underscores the value of genetic testing in establishing an accurate diagnosis and guiding treatment.<\/jats:p>","DOI":"10.3390\/children13060841","type":"journal-article","created":{"date-parts":[[2026,6,26]],"date-time":"2026-06-26T08:43:57Z","timestamp":1782463437000},"page":"841","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Postsynaptic Congenital Myasthenic Syndrome Mimicking Limb\u2013Girdle Muscular Dystrophy Associated with an Alternatively Spliced Exon in CHRNB1: A Case Report and Literature Review"],"prefix":"10.3390","volume":"13","author":[{"given":"Wen-Kan","family":"Feng","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Sijhih Cathay General Hospital, New Taipei City 22174, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1292-3086","authenticated-orcid":false,"given":"Kun-Long","family":"Hung","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Fu Jen Catholic University Hospital, New Taipei City 24352, Taiwan"},{"name":"School of Medicine, Fu Jen Catholic University, New Taipei City 24205, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4607-696X","authenticated-orcid":false,"given":"Ting-Hao","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, Sijhih Cathay General Hospital, New Taipei City 22174, Taiwan"},{"name":"Department of Pediatrics, Fu Jen Catholic University Hospital, New Taipei City 24352, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1016\/j.jneuroim.2008.06.026","article-title":"Congenital myasthenic syndromes in childhood: Diagnostic and management challenges","volume":"201","author":"Kinali","year":"2008","journal-title":"J. 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