Amyotrophic Lateral Sclerosis (ALS) - Lou Gehrig's disease - Symptoms - Diagnosis - Treatment

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal disease that is  caused by the degeneration of motor neurons that control  voluntary muscular movements of the body. It is also called Lou Gehrig's disease after the famed American baseballer by the same name, who died of ALS  in 1941, aged 37. Stephen Hawking, the world renowned physicist, is among those afflicted, currently alive.



ALS is classified under  'motor neuron disorders' and is characterized by the gradual degeneration of motor neurons which are nerve cells localized  in the brain, brainstem, and spinal cord which control communication  between the nervous system and the voluntary muscles all over  the body.

Upper motor neurons (brain)
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Lower motor neurons (spinal cord)
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Voluntary muscles

The disorder begins when the upper and lower motor neurons  degenerate  and stop sending signals to the muscles bringing about weakening, twitching (fasciculation) and their eventual atrophy. Initially the disease may manifest as difficulty in walking or running, writing or speech. The patient may ultimately loose control over all voluntary movements  and there comes a stage when the brain  no longer controls voluntary movements of the body and the patient becomes weak and is unable to walk or move  his arms or legs.

Breathing too becomes difficult as the muscles of the chest and the diaphragm are damaged. Although  a ventilator may help for a while, the afflicted persons very often die from respiratory failure within 3-5  years of disease onset.

Generally, the intelligence of the patient is not impaired. However certain changes in cognitive function is brought about such as memory loss, problems with making decisions and depression. However, the person's ability to see, smell, hear, taste or touch is not affected.

ALS is one of the common neuromuscular diseases which mostly affects men,  more than women, of all races and ethnic background. It usually affects people between the ages of 40 and 60.

The actual causes of ALS are not very clear. Familial predisposition has been implicated, but in the vast majority of affected people it occurs de novo. In 90-95% of ALS cases the disease is not familial, but occurs sporadically.

5-10%  of all ALS cases are genetically determined. One-fifth of these cases occur due to a mutation in the gene SOD1 that codes for the enzyme superoxidase dismutase 1. It is obvious that other genes are involved and are waiting to be discovered.

ALS cannot be completely cured but medications are available that can control the symptoms and prolong life. Some people can live for as long as even ten years with proper treatment.