Multiple sclerosis.

The cause of multiple sclerosis is unknown but seems to be multifactorial. Susceptibility or resistance may be genetically determined; something in the environment interacts with the human host at the proper age to cause biochemical and structural lesions in the central nervous system. The systemic immune response and the response of the central nervous system become involved. Although multiple sclerosis cannot yet be cured, many clues are leading to an effective palliative therapy. Suppression or modulation of the immune responses may be the key to developing that treatment. If the environmental agent is one or several viruses, then antiviral regimens will be appropriate. Research must therefore continue at both basic science and clinical levels.