Myotonic Dystrophy commonly involves which body systems beyond skeletal muscles?

• A. Only skeletal muscle
• B. Cardiac, respiratory, GI, ocular systems
• C. Nervous system only
• D. Muscles of the limbs

Answer: (B)

Myotonic dystrophy is a multisystem disorder. Beyond skeletal muscles, it commonly affects the heart, lungs, digestive tract, and eyes. Cardiac conduction defects and arrhythmias can occur, reflecting heart involvement. Weakness of respiratory muscles can lead to breathing problems. The gastrointestinal tract may show dysphagia and motility issues, while the eyes can develop early cataracts and ptosis due to smooth muscle involvement. This broad pattern across several organ systems is why the option listing cardiac, respiratory, GI, and ocular involvement best captures the typical disease spectrum. The other choices are too narrow, either focusing only on muscles or implying involvement of just one system.