Amyotrophic Lateral Sclerosis (ALS), which is sometimes called Lou Gehrig’s disease, involves the death of the nerve cells that control respiratory muscles including ones for walking, arm movement and breathing. This is a progressive and fatal disease, with initial complaints about muscle spasticity followed by progressively worsening muscle weakness.
Ninety to ninety-five percent of the cases are due to spontaneous occurrence, where as in 5-10% there is a familial trend in one of the parents. Over a dozen gene mutations have been linked to ALS. There is no single test for ALS, but the presence of upper and lower motor neuron dysfunction is highly suggestive, and electromyography and nerve conduction studies can aid in the diagnosis. The exact cause of ALS remains unknown.
Current treatment may involve riluzol, a drug that reduces the release of glutamate. In clinical trials, riluzol extended life by several months, especially in patients who had difficulty swallowing. It also extended the time before an individual needs respiratory support. Other assistance is mainly aimed at supporting the patient in the face of weakened muscular capacity with a variety of supportive aids and respiratory assistance devices.
Part of the challenge in caring for patients with ALS is the medications that may be helpful are unable to cross the blood-brain barrier (BBB), so they cannot get to the part of the brain to have their effect. One upcoming proposal is a phase 1 safety and feasibility study that intends to transiently open the BBB in the region of the motor cortex in patients with moderate ALS. If this can be accomplished, the hope is that it can be coupled with therapeutic agents that can penetrate the BBB for a beneficial effect. This project has yet to begin, but many hope that it can open the door to more effective treatment for ALS.
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