How is Duchenne muscular dystrophy
The diagnosis may be suspected because of the child's
When looking for signs of DMD, it is important to watch
the child running and getting up from the floor - the
muscle weakness is more noticeable during these activities.
Tests are needed before DMD can be diagnosed. The
first step in making the diagnosis is a blood test. This
tests for creatine kinase. Children with DMD always
have a very high level of creatine kinase (about 10-100
times normal). Therefore if a child's creatine kinase level
is normal, then DMD is ruled out. If the creatine kinase
level is high, further tests are needed to see whether this
is due to DMD or to some other condition.
The next step in diagnosing DMD involves either a muscle biopsy and/or genetic tests:
A muscle biopsy involves taking a small sample of a muscle, under local anaesthetic. The sample is examined under a microscope using special techniques to look at the muscle fibres and the dystrophin protein.Genetic tests are done using a blood sample. The DNA in the blood is tested to look at the dystrophin gene. This test can diagnose most cases of DMD.