- CK Tests
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Measures the muscle enzyme phosphokinase (CK)
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If a muscle is damaged CK will leaks out of it into the blood
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If a blood test reveals a CK level of 50-100 times greater than normal, muscles are damaged
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A high CK level suggests that the muscles are the likely cause of the weakness, but does not show exactly what the muscle disorder might be as this enzyme is often slightly raised in other types of dystrophy
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But, an increase in CK is far greater in DMD than other dystrophies as approximately 70% of DMD carriers show a slightly raised CK level
- DNA Studies:
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DNA studies are undertaken in an attempt to establish a definite diagnosis
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Abnormalities responsible for DMD may be one of three different types: deletions (missing parts), duplications (additional parts), point mutations (changed parts)
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Deletions and duplications which are the most common types of mutations
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Point mutations require further testing using different techniques to analyse the DNA and it could take a lot longer for a diagnosis if there isn’t a family history of DMD
- Muscle Biopsy:
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On rare occasions when DNA testing does not give a definite diagnosis a muscle biopsy is required
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A small piece of muscle tissue is taken with a needle (usually from the thigh) which is then tested in the laboratory
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The muscle tissue is examined microscopically for dystrophin protein.
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The amount of or lack of the protein dystrophin will determine the diagnosis
While there is no cure it should be diagnosed early because:
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They should contact a neuromuscular specialist so if and when treatment becomes available they have access to it
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So medical, physiological and social needs can be anticipated, planned for and addressed when they arise
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So the parents and female relatives can receive genetic counselling concerning the risk in future pregnancies