Home Muscular dystrophy: Duchenne MD

Muscular dystrophy: Duchenne MD

Types

Defining Characteristics

Pseudohypertrophy (large calves), scoliosis, lumbar lordosis, protuberant abdomen, toe walking, Gower’s sign,  mental deficits

Disease Development

Caused by X-linked recessive mutation of dystrophin, resulting in absent (or <5%) dystrophin. W/o dystrophin, the sarcolemic membranes are leaky, there's secondary inflammation from necrosis, and cycles of degeneration & regeneration.

Potential Causes

Absent dystrophin

Epidemiology

Most common MD, especially in children
1/3000 live births

Lab/Imaging

Histology? Increased CT, fibrofatty and macrophage infiltration, variable muscle fiber size and abnl cells, bluish fibers are regenerating (inc DNA)
CK levels 10-100x>nl

Conventional Treatment

Steroids at early age prolongs ability to walk

Complications

Associated w/ dilated cardiomyopathy
No cure! Limited life expectancy