Clinical and Genetic Spectrum of Myotonia Congenita in Turkish Children


Creative Commons License

Öz Tunçer G., Sanri A., Aydin S., Hergüner Ö. M., Özgün N., Kömür M., ...Daha Fazla

Journal of neuromuscular diseases, cilt.10, sa.5, ss.915-924, 2023 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 10 Sayı: 5
  • Basım Tarihi: 2023
  • Doi Numarası: 10.3233/jnd-230046
  • Dergi Adı: Journal of neuromuscular diseases
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, MEDLINE
  • Sayfa Sayıları: ss.915-924
  • Anahtar Kelimeler: child, CLCN1, genetic heterogeneity, Myotonia congenita
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

BACKGROUND: Myotonia congenita is the most common form of nondystrophic myotonia and is caused by Mendelian inherited mutations in the CLCN1 gene encoding the voltage-gated chloride channel of skeletal muscle. OBJECTIVE: The study aimed to describe the clinical and genetic spectrum of Myotonia congenita in a large pediatric cohort. METHODS: Demographic, genetic, and clinical data of the patients aged under 18 years at time of first clinical attendance from 11 centers in different geographical regions of Türkiye were retrospectively investigated. RESULTS: Fifty-four patients (mean age:15.2 years (±5.5), 76% males, with 85% Becker, 15% Thomsen form) from 40 families were included. Consanguineous marriage rate was 67%. 70.5% of patients had a family member with Myotonia congenita. The mean age of disease onset was 5.7 (±4.9) years. Overall 23 different mutations (2/23 were novel) were detected in 52 patients, and large exon deletions were identified in two siblings. Thomsen and Becker forms were observed concomitantly in one family. Carbamazepine (46.3%), mexiletine (27.8%), phenytoin (9.3%) were preferred for treatment. CONCLUSIONS: The clinical and genetic heterogeneity, as well as the limited response to current treatment options, constitutes an ongoing challenge. In our cohort, recessive Myotonia congenita was more frequent and novel mutations will contribute to the literature.