Which condition is commonly associated with early onset in boys and rapid progression?

• A. Duchenne Muscular Dystrophy
• B. Becker Muscular Dystrophy
• C. Limb-Girdle Muscular Dystrophy
• D. Myotonic Dystrophy

Answer: (A)

Early onset in boys with rapid progression is classic for Duchenne muscular dystrophy. It’s caused by mutations in the dystrophin gene on the X chromosome, so it’s inherited as X-linked recessive and primarily affects males. Symptoms typically begin between ages 2 and 5 with rapid proximal weakness, frequent falls, and a Gowers’ sign when getting up from the floor. Calf muscles often become visibly enlarged (pseudohypertrophy), and the progression is fast, with most boys losing ambulation in their early teens and facing cardiopulmonary complications later. Becker muscular dystrophy involves the same gene but starts later and progresses more slowly, whereas limb-girdle and myotonic dystrophies have different inheritance patterns and clinical courses, not the same early, aggressive course in boys.