Myotonic dystrophy type 1 presenting with dyspnea: A case report

Area of Science:

• Genetics
• Neuromuscular Disorders
• Pulmonology

Background:

• Myotonic dystrophy type 1 (DM1) is a multisystem genetic neuromuscular disorder.
• The variable clinical presentation of DM1 hinders early diagnosis and treatment.
• Cardiopulmonary involvement is a significant feature of DM1.

Observation:

• A 35-year-old female presented with dyspnea and sleep apnea as primary symptoms.
• Clinical examination revealed low limb muscle tension.
• Electromyography confirmed myotonia, and genetic testing identified CTG repeat expansion in the DMPK gene, confirming DM1.

Findings:

• DM1 diagnosis confirmed by genetic testing showing >50 CTG repeats in the DMPK gene.
• The patient's initial presentation was primarily respiratory, highlighting symptom variability.
• Electromyography demonstrated characteristic myotonia potentials.

Implications:

• Pulmonologists should consider DM1 in patients presenting with dyspnea.
• Improved clinician understanding of DM1 is essential for early diagnosis.
• Timely diagnosis of DM1 can significantly enhance patient quality of life.