Congenital and infantile myotonic dystrophy

Area of Science:

• Genetics and Neurology
• Pediatric Medicine
• Rare Diseases

Background:

• Myotonic dystrophy (DM) is a multisystemic disorder caused by gene defects.
• Myotonic dystrophy type 1 (DM1) is the sole cause of childhood DM, stemming from CTG repeat expansions.
• DM1 presents a broad clinical spectrum, from antenatal to adult forms, with significant variability.

Purpose of the Study:

• To detail the clinical continuum and multisystemic involvement of DM1, focusing on childhood-onset.
• To describe the hallmark brain involvement and presenting symptoms in pediatric DM1.
• To outline the progression of muscular and orthopedic manifestations and other organ systems affected.

Main Methods:

• Review of clinical presentations and genetic defects associated with DM1.
• Analysis of phenotypic spectrum, from congenital to adult forms.
• Description of multisystemic involvement, including neurological, muscular, and orthopedic aspects.

Main Results:

• Childhood-onset DM1 is characterized by brain involvement, learning difficulties, and psychopathological manifestations.
• Congenital DM1 represents the most severe form, with neonatal hypotonia and respiratory failure.
• Muscle weakness is typically moderate in childhood, worsening later, with orthopedic issues and occasional cardiac arrhythmias.

Conclusions:

• DM1 presents a complex, multisystemic disease with significant neurological impact in childhood.
• Current management is symptomatic, but advances in pathophysiology pave the way for future molecular therapies.
• Understanding the diverse clinical spectrum is crucial for diagnosis and management of DM1 patients.