| Diagnosis Methods for DMD |
 |
Methods of diagnosis on DMD |
|
| |
Although Duchenne muscular dystrophy is an
inherited disease, and present from the initial stages of fetal
development, there is no physical indication at birth that the baby
is anything less than perfectly formed.
It is rare for any delay in development to be noticed in the first
year of life. Problems are usually not evident until eighteen months
to four years of age. On average a diagnosis is not made until the
child is five, although with increasing awareness of the problem,
some boys are diagnosed earlier. At least half of affected boys
do not walk until eighteen months of age or later. In retrospect,
almost all parents have noted that their child never walked or ran
normally. Over the first few years of life these children have difficulty
climbing and getting up from the floor. Parents often comment that
their child falls frequently. Walking up on the toes (toe-walking)
is common. These are the means of diagnosis to confirm about Duchenne
MD in a child |
| |
|
Creatine kinase (CPK/CK) test
: |
|
| |
The body creates an enzyme called 'creatine kinase' (also known
as CPK/CK) that normally lives inside muscles. That enzyme (protein)
is important for energy production within muscle fibers. When muscles
are functioning normally, CPK levels in the bloodstream are relatively
low. But when muscles are damaged, the muscle cells split open, causing
their contents to spill out into the bloodstream. This creates a rise
in the levels of CPK in the blood. In Duchenne muscular dystrophy(DMD)
there may be 10 to 100 times the normal amount. Measuring CPK levels
may verify that there has been muscle damage and may indicate more
muscle damage to come. |
| |
|
|
Electromyography (EMG) |
|
| |
When muscles contract (shorten) there is electricity flowing through
the muscle tissue. An abnormal muscle has an abnormal pattern of electricity
that can be recognized and recorded using special equipment. An EMG
test involves putting a small needle through the skin into a muscle
and recording the pattern of electricity in the muscle when it is
contracting. |
| |
|
|
Muscle biopsy |
|
| |
Once a CPK test comes back showing high levels of the enzyme in
the blood, conclusions can be made that muscles are likely, damaged.
But a CPK test alone cannot diagnose Duchenne MD. In order to determine
the cause of the muscle damage, doctors will usually perform a muscle
biopsy. This requires a doctor to surgically remove a small sample
of muscle and examine it closely to determine what is happening inside
the cells. This test is the most reliable way to diagnose Duchenne
MD, distinguish it from the other inflammatory disorders, and distinguish
it from other Muscular Dystrophies.. |
| |
|
|
DNA test |
|
| |
DNA testing (using blood cells or muscle cells) remains the best
way to obtain exact genetic information leading to a conclusive Duchenne
MD diagnosis. In the future, as this type of testing becomes more
commonplace, it will lead to faster diagnosis of all Muscular Dystrophies.
|
| |
|
| |
|
| |
