Duchenne muscular dystrophy
Type of disease: Rare conditions
Duchenne muscular dystrophy (DMD) is a genetic condition that causes progressive muscle weakness and a decrease in the amount of muscle tissue (atrophy). DMD is the most common type of muscular dystrophy and typically affects males. DMD occurs when a person inherits a change (mutation) in the gene that makes dystrophin, a protein that protects muscle tissue. Signs and symptoms typically begin to show during childhood and may include frequent falls, difficulty getting up from a lying or sitting position, trouble running or jumping, walking on toes, large calf muscles, muscle pain and stiffness, and learning disabilities. As the disease progresses, children may have trouble breathing and swallowing, may lose the ability to walk or sit up, and are typically wheelchair dependent in their teens. Another symptom of DMD is weakness of the heart muscle (cardiomyopathy), which may cause shortness of breath, abnormal heartbeat (arrhythmia), and extreme tiredness (fatigue).
DMD is inherited in an X-linked recessive pattern. Males have one copy of the DMD gene while females have two copies. Males who have a mutation in their only copy of the gene have the condition, while females with a mutation in one of their two copies typically do not. In order to diagnose this condition, your doctor will take a detailed medical history, perform a physical exam, and likely perform one of many possible tests, which can include collecting and examining a small piece of muscle tissue (muscle biopsy), measuring electrical activity in your muscles (electromyography), measuring the amount of CK enzyme in your blood, as well as monitoring the heart and lungs. DMD gene testing is typically needed to confirm the diagnosis. Unfortunately, there is no cure for DMD. This is a very serious condition and if your child has this diagnosis, it is helpful to speak with a doctor, genetic counselor, or therapist to gain additional information and support.