Congenital myotonic dystrophy

S Gulati1, M Kabra, S Gera

  • 1Department of Pediatrics, All India Institute of Medical Sciences, Sir Ganga Ram Hospital, New Delhi, India.

Insights

Myotonic dystrophy, a frequent genetic disorder, presents with varied symptoms from birth. Genetic testing confirms the CTG repeat expansion, enabling precise diagnosis and prenatal screening for this multisystem disease.

Area of Science:

  • Genetics
  • Neurology
  • Pediatrics

Background:

  • Myotonic dystrophy is the most common autosomal muscular dystrophy.
  • It is characterized by variable expressivity affecting multiple organ systems.
  • Congenital myotonic dystrophy presents with severe neonatal symptoms.

Observation:

  • A case of congenital myotonic dystrophy is presented.
  • The patient exhibited facial dysmorphism, hypotonia, talipes, and feeding/respiratory issues.
  • Developmental delay and percussion myotonia were noted later, along with maternal myotonia.

Findings:

  • Both patient and mother showed CTG trinucleotide repeat expansion in the myotonic protein kinase gene.
  • This molecular defect is specific for myotonic dystrophy.
  • Genetic confirmation allows differentiation from other neuromuscular disorders.

Implications:

  • Specific molecular diagnosis of myotonic dystrophy is now possible.
  • Accurate prenatal diagnosis can be offered to families.
  • Understanding the genetic basis aids in managing this complex disorder.

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