Myotonic Dystrophy Type 2. Congenital myotonic dystrophy has only been seen in Type 1 myotonic dystrophy and not in Type 2. Myotonic Dystrophy type 2 DM2 DM2 was previously named proximal Myotonic Myopathy or PROMM and shares many of the clinical and genetic features of DM1.
They result in multisystem disorders characterized by skeletal muscle weakness and myotonia difficulty relaxing muscles after use cardiac abnormalities cataracts and other abnormalities. Symptoms usually show up around your 20s. Like classic myotonic dystrophy 1 this disorder also results from an abnormal number of repeats in this case of CCTG.
Myotonic dystrophy type 2 one of the two types of myotonic dystrophy is an inherited muscular dystrophy that affects the muscles and other body systems eg heart eyes and pancreas.
Myotonic dystrophy type 2 DM2 is characterized by myotonia and muscle dysfunction proximal and axial weakness myalgia and stiffness and less commonly by posterior subcapsular cataracts cardiac conduction defects insulin-insensitive type 2 diabetes mellitus and other endocrine abnormalities. Phenotypes of DM1 and DM2 are similar but there are some important differences including the presence or absence of congenital form muscles primarily affected distal vs proximal involved muscle fiber types type 1 vs type 2 fibers and some associated. Muscle biopsy showing mild myopathic changes and grouping of atrophic fast fibres type 2 highlighted. It affects about 1 in 8000 people worldwide.
