Types
Defining Characteristics
Maternal anticipation, asymmetric distal weaknes w/ myotonia, pt can make a fist but can’t open it back up easily; frontal balding, cataracts, cardiac conduction probs, endocrine dysfunction (hypogonadism, insulinR), GI hypomotility
Disease Development
Autosomal dominant inheritance associated with trinucleotide CTG repeats in myotonin-protein kinase gene on C19
Potential Causes
Maternal anticipation (increases number of CTG rpts)
Epidemiology
5-20/100,000 live births
Lab/Imaging
Clinical exam
Complications
Multisystem disorder; possible complete heart block