Gokcen Oz Tuncer, Aslıhan Sanrı, Gülbahar Kurt Bayır, Ilknur Erol, Merve Oztürk, Hasan Tekgül, Özlem Hergüner, Gültekin Kutluk, Dilek Cavusoglu, Hande Gazeteci Tekin, Mustafa Kömür, Ayse Aksoy

Objectives: Myotonic dystrophy type 1 (DM1) is a multisystem disorder with a broad spectrum of severity caused by autosomal dominant inherited unstable expanded CTG repeat in the DMPK gene. DM1 is the most common type of adult-onset muscular dystrophy. In this study, it was aimed to investigate the genetic and clinical features of pediatric-onset cases, which are less common. Methods: Demographic, genetic and clinical data of the patients younger than 18 years with a genetically confirmed diagnosis, from nine centers in different geographical regions of Turkey were retrospectively investigated. Results: Twenty-six patients (mean age 11.9 years, 50% females, with 30.8% congenital, 53.8% pediatric, 15.4% juvenile form) were included. Antenatal history of polyhydramnios (7.7%), reduced fetal movements (26.9 %), low birth weight (15.3%), and prematurity (23.1%) were evident. Six patients needed mechanical ventilator care in the neonatal period. 22 patients had a family history of DM1 (13 maternal/ 9 paternal). The initial clinical manifestations were muscle weakness (53.9%), hypotonia (38.4%), myotonia (26.9%), developmental delay (23%), and abnormal gait (7.6%). Various findings showing multisystem involvement (3/26 cardiac dysrhythmia, 2/26 type 1 diabetes mellitus, 1/26 polycystic ovary syndrome, 12/26 psychiatric comorbidities (6/12 attention deficiency and hyperactivity), 6/25 gastrointestinal system findings, 3/25 abnormality in cranial magnetic resonance imaging) were detected. 15 patients were receiving carbamazepine and two mexiletine. 13 of them had partial treatment response. Conclusion: The genetic and clinical findings of pediatric DM1 patients are diverse, which requires a multi-faceted approach and management.
Keywords: Myotonic Dystrophy Type 1, Child

Gokcen Oz Tuncer
Ondokuz Mayıs University, Faculty of Medicine
Turkey

Aslıhan Sanrı
University of Health Sciences, Samsun Training and Research Hospital
Turkey

Gülbahar Kurt Bayır
Ondokuz Mayıs University, Faculty of Medicine
Turkey

Ilknur Erol
Baskent University, Faculty of Medicine
Turkey

Merve Oztürk
Kocaeli University, Faculty of Medicine
Turkey

Hasan Tekgül
Ege University, Faculty of Medicine
Turkey

Özlem Hergüner
Cukurova University, Faculty of Medicine
Turkey