Differential Diagnostic Decision-Making Scheme for Limb Weakness and Bilateral Temporal Pole Abnormal Signals

Background : Myotonic dystrophy type 1 (DM1) is an autosomal dominant disorder caused by an abnormal expansion of the CTG trinucleotide repeat in the 3′UTR region of the DMPK gene on chromosome 19q13.3. There is currently no cure for DM1, and early diagnosis along with multidisciplinary evaluation and intervention may be important in delaying its progression. However, its clinical manifestations are diverse, making diagnosis quite challenging. Case Report : A 29-year-old female patient with a 6-year history of progressive limb weakness accompanied by muscle twitching. The patient also exhibited clinical myotonia and abnormal findings in both temporal lobes on cranial MRI. She was finally diagnosed with DM1 through electromyography and genetic testing.