Duchenne muscular dystrophy (DMD) is a rare genetic disease that is characterised by severe and progressive skeletal and cardiac muscle weakness and atrophy. DMD occurs primarily in males, though in rare cases may affect females with less severe muscle weakness. The disease often debuts between the ages of three and six years. The symptoms of DMD include progressive weakness and loss (atrophy) of skeletal and heart muscles. Early signs of DMD may include delayed ability to sit, stand, or walk and difficulties learning to speak. Muscle weakness is usually noticeable in early childhood. Because of the rapid progressive nature of the disease, most patients require assistance in the form of a wheelchair by their teenage years, as the disease gradually extends to more muscle groups. Heart and breathing problems such as cardiompyopathy may also begin in the teen years and lead to serious, life threatening complications. In addition to the decay and necrosis of muscle fibers, children suffering from DMD are affected by reduced bone density making them prone to fractures, especially in the hips and spine.
DMD is caused by genetic changes in the DMD gene. DMD is inherited in an X-linked recessive pattern and may occur in people who do not have a family history of DMD. While there is no known cure for DMD, there are treatments that can help control symptoms. DMD is diagnosed in young boys based on clinical examination, signs and symptoms, family history, and genetic testing. Blood tests looking for increased levels of muscle enzymes are used to check for muscle damage.
