Delete
Are you sure you want to delete this?
Card
-
Title
-
Myotonic Dystrophy Type 1
-
ImagePath
-
-
System
-
trinucleotide repeat expansion
-
Overview
-
AD CTG repeat expansion in DMPK gene causing myotonia & multisystem involvement.
-
Pathophysiology
-
CTG expansion → abnormal RNA binding proteins → splicing defects (eg, CLCN1) → myotonia, endocrine issues.
-
Presentation
-
Difficulty releasing handshake (grip myotonia), cataracts, balding, testicular atrophy, arrhythmias.
-
Diagnosis
-
PCR repeat sizing; electromyography: myotonic discharges.
-
Management
-
Mexiletine for myotonia, slit‑lamp for cataracts, pacemaker for heart block.
-
Epidemiology
-
1 : 8000; anticipation via maternal transmission.
-
Tags
-