Duchenne muscular dystrophy (DMD) is a genetic disorder characterized by progressive muscle degeneration and weakness due to the alterations of a protein called dystrophin that helps keep muscle cells intact. А particular gene on the X chromosome that, when flawed (mutated), leads to DMD. 

SYMPTOMS

The first signs of the disease include:

• Clumsy (heavy) gait, walking on tiptoes due to increased tone in the calf muscles

• Constant fatigue

• Frequent falls

• Difficulty performing motor skills such as running or jumping

• Gowers' sign (the child helps himself to stand up using his hands)

• Increased lumbar lordosis

• Contractures (a shortening of muscles, tendons, skin, and nearby soft tissues that causes the joints to shorten and become very stiff, preventing normal movement)

• Progressive proximal muscle weakness in the legs and pelvis. Over time this weakness spreads to the arms, neck and other parts of the body. Pseudohypertrophy (enlargement of the calf and deltoid muscles; patients experience difficulty climbing stairs)

• Loss of the ability to walk by the age of 12

• Skeletal deformities (scoliosis)

PREVALENCE

Duchenne muscular dystrophy affects approximately 1 in 4,000 individuals, making it the most common type of muscular dystrophy. Typically, DMD affects only males, while females can sometimes be carriers of the disease. Mutations in the dystrophin gene can be inherited or arise spontaneously.

CAUSES AND INHERITANCE PATTERN

DIAGNOSIS