What is Duchenne Muscular Dystrophy?
Duchenne muscular dystrophy (DMD) is an inherited disorder which affects males only. It is the most common lethal disorder affecting children. DMD affects approximately 1 in 3,500 live male births. Due to the x-linked factors, children inherit the gene for DMD from their maternal lineage. Mothers, for the most part, do not exhibit any symptoms and, usually, do not know they are carriers of this deficient gene. (approximately 30% of cases are due to spontaneous genetic mutation and not attributed to an inheritance.) Becker muscular dystrophy (BMD) is similar to DMD although is less common and has a slower progression of muscle weakness.
Signs and Symptoms of Duchenne
The first signs of muscle weakness are usually noticed between the ages of 2 to 5. The weakness is commonly dismissed in the beginning as laziness or clumsiness. The weakness progresses as the boys get older and the symptoms become much more apparent. The boys exhibit what appear to be abnormally large calf muscles. These are called “pseudohypertrophic” because it is not all muscle but is also fibrous tissue which has infiltrated the muscle cells.
Soon they exhibit some trouble getting up from the floor, they have trouble keeping up with their peers, they begin walking on their toes for some or all of the time and fatigue easily. Another symptom may be complaints of muscle pain when playing at young ages.
Duchenne Diagnosis
The diagnosis is often missed when the boys are very young. When the presentation of weakness becomes apparent, lab tests are usually run. An extremely high serum creatinine kinase (CK) level is usually found in a simple blood test and a referral to a neurologist will likely be made. A muscle biopsy will reveal the absence of dystrophin, the abnormal fibrous tissue deposits, and the final diagnosis of DMD. Genetic testing is more specific and allows for identification of the type of mutation present.
NOW WHAT?
The information above probably sounds familiar and is not new to most of you. You have heard the dreaded diagnosis, regained composure long enough to do some internet research, maybe more, and now you’re saying, “Now what?” and “Where do we go from here?”
There is a lot of information to take in and many decisions to make. This can be extremely overwhelming. My hope is that this website can help point you in the right direction and enlighten you for the journey ahead.
