Differential diagnoses | Muscular dystrophy

Differential diagnoses

Muscle weakness and atrophy can be symptoms of a number of other conditions that may need to be ruled out. These include above all:

• Diseases of the nerves and spinal cord, e.g. poliomyelitis (“polio”), amyotrophic lateral sclerosis or multiple sclerosis. The exclusion is based on clinical picture, measurement of nerve conduction velocity and electrical muscle activity, which are different from the findings in muscular dystrophy.

  A muscle biopsy can also provide information about the underlying cause of nerve damage.

• Diseases of the “neuromuscular endplate”, the switch point between nerve and muscle, which are caused by autoimmune processes. These include myasthenia gravis or the Lambert-Eaton syndrome, which can also occur in the wake of tumor diseases. Here, too, characteristic differences in the electromyogram, nerve conduction velocity and muscle biopsy are noticeable. Autoantibodies, which would be detectable in the blood and the microscopic preparation in the case of the above-mentioned diseases, are absent in muscular dystrophies.

Therapy

To date, there is no causal therapy for muscular dystrophies. Previous attempts of drug therapy with a wide variety of substances have all been disappointing in the end. For the future, hopes are pinned on a genetic therapy that will remedy the underlying defects in the genetic material or their effects on muscle metabolism, but such attempts are currently in the early stages at best.

For this reason, the therapy of muscular dystrophies is currently based on supportive measures to cushion the consequences of increasing muscle weakness and help patients cope with everyday life. This includes above all physiotherapy to maintain the greatest possible mobility and to prevent incorrect posture. Physical training should only be carried out very carefully to avoid consequential damage to the musculature due to overloading.

The use of anabolic steroids is not advisable due to serious side effects and unproven benefits, and is only justifiable in exceptional cases under the close supervision of a specialist doctor. Psychotherapeutic care can help those affected to cope with life with the diagnosis of a chronically progressive disease; contact with one of the numerous self-help groups can facilitate access to help. As with all hereditary diseases, human genetic counselling is advisable for further family planning; the sense and benefit of prenatal diagnostics must be decided in each individual case.