Muscular Dystrophy / Duchenne Muscular Dystrophy - Diagnosis

Diagnosis

1. Clinical examination

Clinical examination of a male child by the pediatrician raise suspicion of DMD

2. Creatinine Phosphokinase

Assay

As the muscle cells die, the affected cells release the enzyme creatinine phosphokinase (CPK) into the blood. Patients with DMD therefore have high levels of the enzyme in their blood (20 times the upper limit of normal). This test was the only available method to detect the presence of the disease, prior to 1982.

3. Electromyography

An examination that tests the electrical activity of the muscle. In muscular dystrophy, the affected muscles display reduced electrical activity.

4. Muscle Biopsy

A test in which a small section of the affected muscle is examined for presence of minute changes under the microscope.

5. Dystrophin Assay

As patients with DMD have defective dystrophin gene, there is impairment in the production of the dystrophin protein. There is usually a complete deficiency of dystrophin in 99% of the patients with DMD. This assay is also used to distinguish DMD from other forms of muscular dystrophy. This form of diagnostic tool yields accurate results and can therefore be used to establish the diagnosis.