Amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a clinical entity differentiated during the last few years into definite, probable, possible and suspected ALS. There are many hypotheses trying to explain its genesis: slow virus hypothesis, trace elements, immunologic and trophic factors, excitotoxins, metabolic influences, DNA anomalies, and so on. It is necessary to differentiate ALS like syndromes and ALS variants. Some of the ALS like syndromes can be treated. Only the disease elaborated like that may be submitted to clinical therapeutical trials or molecular-genetic research. Palliative therapy is still necessary. It does not prolong life, it makes its quality better.