Emergency: requires immediate attention
Myotonic dystrophy
Alerts and Notices
Synopsis
Myotonic dystrophy type 1 has distal weakness, with myotonia prominent in the hands; type 2 has proximal muscle weakness (also called PROMM or proximal myotonic myopathy). The signs and symptoms of myotonic dystrophy typically manifest in the third or fourth decade, although they can occur at any age.
Congenital myotonic dystrophy can occur in neonates born to affected mothers. These children have a severe phenotype with prominent weakness, hypotonia, skeletal abnormalities, feeding difficulties, and respiratory distress at birth.
Codes
ICD10CM:G71.11 – Myotonic muscular dystrophy
SNOMEDCT:
77956009 – Steinert myotonic dystrophy syndrome
Look For
Subscription Required
Diagnostic Pearls
Subscription Required
Differential Diagnosis & Pitfalls
- Myotonia congenita
- Paramyotonia congenita
- Duchenne muscular dystrophy
- Becker muscular dystrophy
- Emery-Dreifuss muscular dystrophy
- Limb-girdle muscular dystrophy
- Fascioscapulohumeral muscular dystrophy
- Oculopharyngeal muscular dystrophy
- Spinal muscular atrophy
- Pompe disease
- McArdle disease
- Carnitine deficiency
- Carnitine palmitoyltransferase deficiency
- Myasthenia gravis
- Polymyositis
- Stiff-person syndrome
- Tetanus
Best Tests
Subscription Required
Management Pearls
Subscription Required
Therapy
Subscription Required
References
Subscription Required
Last Reviewed:10/18/2018
Last Updated:01/20/2022
Last Updated:01/20/2022
Emergency: requires immediate attention
Myotonic dystrophy