[Association of amyotrophic lateral sclerosis and multiple sclerosis].

A twenty-five year old woman developed a progressive right hemiparesis which remitted within three months, without treatment. The diagnosis was a first relapse of multiple sclerosis. After a 10 year fully asymptomatic period, the patient developed weakness of the legs with falls and swallowing difficulties. Fasciculations and amyotrophy were present in the limbs and the tongue. There were no sensory abnormalities. The electromyogram confirmed the peripheral neurogenic degeneration with signs of anterior horn involvement. Motor and sensory nerve conductions were normal. Muscle weakness and atrophy increased in the limbs and the bulbar territory and the patient died nine months later. The autopsy showed characteristic "old" plaques of multiple sclerosis in the cerebrum with anterior horn cell and pyramidal tracts degeneration, typical of amyotrophic lateral sclerosis, in the spinal cord. Although exceptional, this association of amyotrophic lateral sclerosis and multiple sclerosis leads to the discussion of an etiological immunological dysregulation common to these two diseases.